Final combined guilford journals of chemistry volumes 1 6

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Table of Contents: Three-dot Nozzle Causes an Eruption Averaging 32.7% Higher than Commonly-Used One-Dot Nozzle By: Allison B, Sammy C, and Ashley H………………………………….…. …4 An Increased Drop Height Causes Only 0.3 grams Less Soda to Leave the Bottle During a Diet Coke and Mentos Eruption; Evidence of Very little Change By: Rachel G. and Emily S………………………………………………………………………..8 Mentos Mashed Into a “Pancake” Erupt, on Average, 48% Lower than Regular Mentos By: Henry R. and John R……………………………………………………………………………….....12 Loud Low Pitch Sounds Produce a 21% Increase in Eruption Height When Mixing Minty Mentos With Regular Coca Cola By: Jack D. and Kyle E....……………………...…………….17 Sprite Zero Erupts 7% Higher than Diet Coke in Comparison to Four Sodas By: Lucila K. and Lindsay L……………………………………………………………………………………………..20 The Diet Coke and Mentos Eruption Using the Standard Geyser Tube Erupted 52.3% Higher than the Modified Nozzle By: Jackson I., Sonny C., Tim K………..……………………23


Minimizing the CO2 Lost During the Application of the Geyser Tube Increases the Pressure within the Bottle but Decreases the Height by 8.54% By: Kate V. and Sophie K…….27 Mentos Heated to 30º Celsius Cause an Eruption of Diet Pepsi 32.8% Higher Than Mentos at 25º Celsius. By: Cole H., Sean H., and Logan F………………………………………………...31 Amount of Carbonation Matters - Height of Eruption Decreases 80% When Diet Coke Bottles Opened 48 Hours Prior to Eruption By: Jaimie C and Becca W………………………..38 Coated Fruit Mentos Produce an Eruption Height 35.9% Greater than Those with Removed Coating Report by: Joe I. Tested by: Isaac A. Chris C. and Joe I……………………..42 Crushed Mentos Create an Eruption that is, on average, 44 cm Less than Full Mentos By: Laurel Z. and Ashley I. ..……………………………………………………………………48 The Effect of Different Diet Soda Brands on the Height of Mentos Eruptions By: Mackenzie C. Natalia P. Amanda P……………………………………………………………...50 Whole Mentos Have a 15% Increase of Eruption Height Compared to Mentos that Were Broken into Halves and Quarters By: Morgan D. and Sami C………………………………….55 The Larger Tube Angle, 360˚, produces a 65% Decrease in the Height of the Mint Mentos Eruption in Comparison to a 0˚ Tube Angle By Sydney S. and Krissa C…………...….59


The Effect of Putting 5,7,9, and 11 Mentos to Change the Height the Soda Erupts to 92 Bricks By: T.J. W, Luke N…………………………………………………………………..…..63 Mint- Fruit Combinations Can Erupt 8% Higher than Mint or Fruit Alone in a Mentos Eruption By Grace C. and Madisen P……………………………………………………………66 Various Holes and Designs Placed On Tape Can Significantly Affect Mentos Eruption By Kathryn B. and Katie E………………………………………………………………………70


The Guilford Journal Of Chemistry Volume 1 Number 1 October 19, 2007 This issue is dedicated to the investigation of the well-known Mentos Eruption. Several discoveries are recorded for the first time in this issue, including: Cold Mentos increase the height of a mentos eruption A method for extremely long (1 minute) Mentos eruptions A method for remote-controlled Mentos eruptions A method for creating a “Mentos mist�


The Guilford Journal of Chemistry Dr. Harry Brielmann, Editor

The premier, state of the art venue for publication and broad dissemination of first-rate, fundamental research in all of chemistry and Mentos Research.

Contributors to the Mentos & Diet Coke Experiment Effect of Surface Coatings: Jennifer A Carly C Different Carbonated Drinks and Mentos: Zach B Ethan S The Effect of Mentos Temperature: Rachel C Emma S Diameter of Nozzle Size: Aaron D Travis D The Effect of Diet Coke Temperature: Justin H Delayed Reaction: Stephanie M Mike M Remote Control Eruption: Paul Mulligan Jared Searles Spray Effects and Nozzle Shapes: Gabriella Necklas Kierstin Wall Fruity vs. Minty: Allessia Pascarella Johanna Penry Nozzle Effects: Taylor Smith Rosie Steffen

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Introduction to this Issue This first issue of the Guilford Journal of Chemistry includes groundbreaking discoveries in the field of Mentos Eruptions. In its simplest form, the Mentos eruption involves dropping Mentos candy into a soda (usually diet coke), resulting in a foamy eruption, which can often be several meters in height. The first widely viewed Mentos eruption occurred on September 14, 1999 on the David Letterman show,1 though earlier eruptions using other candies (with less spectacular results) had been used primarily by teachers dating back to the 1980’s.2 In terms of scientiic research this field is still in its infancy, since this area of research has almost no peer-reviewed published research results,3 although numerous videos documenting riveting eruptions are available on the internet,4 and on commercial television.5 Several unverified explanations have been offered to explain the eruption6, usually focusing on the physical shape of the mint (so-called nucleation sites), or on the various ingredients in the mint, particularly gum arabic. It is important to note that none of these hypotheses have been scientifically verified. This journal represents the first attempts to scientifically investigate the mentos eruption. Several previously unrepoted discoveries are documented in this journal. Perhaps the most fascinating discovery was made by Cutler and Smith.7 This featured papers reveals that that the height of a mentos eruption can be dramatically increased by freezing a mentos candy prior to dropping it in the soda. Coupled with the predictable observation that heating a mentos candy will increase the height of an eruption, this creates a bizarre result: the the height of a mentos eruption is relatively high when the candy is cold, low when the candy is at room temperature, and then high again when the candy is warm or hot. This discovery could in principle create world-record eruption heights (the current record is 29.2 feet). Another serendiptous discovery was made by Marsh and Moalli.8 While attempting to create a timedelayed Mentos eruption, they chanced upon a method for sustaining an eruption for over 40 seconds. More importantly, their graph suggests that this method could be applied to create eruptions that occur for several minutes in theory, though there were some occasional reproducibility issues that will have to be addressed. Several of these papers are design-based, in which an eruption of a certain type is desired and executed. Methods for creating several spectacular effects are published in this issue. Those interested in creating a unique misting effect should read the work of Necklas and Wall.9 Those looking for both an extremely high as well as a sustained eruption should turn to the work of Davis and Dillon.10 Space does not permit the higlighting of all articles. However, all of these investigations created spectacular eruptions and we hope you enjoy reading about them Dr. H. Brielmann Editor in Chief The Guilford Journal of Chemistry 4


References: 1. For an informative historical account of the Mentos Eruption, Speve Spanglers website is recommended: (http://www.stevespanglerscience.com/experiment/00000109. Note that the original Letterman Show Mentos Eruption may be viewed on the internet at http://www.chem.uic.edu/marek/letterman0/video/mentos.htm. 2. For accounts of Mentos-like eruptions dating back to the 1980’s, see: Marek http://www.rimmkaufman.com/rkgblog/2007/12/21/steve-spangler/ 3. For example, the search term Mentos gives no results currently from polular scientific search engines currently (2008), including PubMed or Google Scholar. Online material is available from Scientific American (http://science-community.sciam.com/blog-entry/Sciam-Observations/SodaFountains-Diet-Coke-Mentos/300004196) as well as detailed hypotheses by the Royal Society of Chemistry (http://www.chemsoc.org/pdf/learnnet/classicdemos/mentosexplosion.pdf), but no experiments were performed in either case to test their ideas. 4. In addition to YouTube, other websites have arrived that are dedicated to the mentos eruption. Of particular mention is geysertube (http://www.geysertube.com/blog/), where one can view the Mentos Eruption in ultra-slow motion. 5. For example, on the popular television series Mythbusters (http://dsc.discovery.com/fansites/mythbusters/mythbusters.html). 6. Most literature on the Mentos Eruption cites the website of Fred Senese (http://antoine.frostburg.edu/chem/senese/101/consumer/faq/mentos.shtml), however there are no experiments performed or cited in support of these hypotheses.

7. Rachel Cutler and Emma Smith, Guilford Journal of Chemistry, Volume 1, Pages 6-12 (2007). 8. Steffi Marsh and Taylor Smith, Guilford Journal of Chemistry, Volume 1, Pages 13-16 (2007). 9. Gabriella Necklas and Kiersten Wall, Guilford Journal of Chemistry, Volume 1, Pages 33-35 (2007). 10. Aaron Davis and Travis Dillon, Guilford Journal of Chemistry, Volume 1, Pages 17-18 (2007).

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Mentos Eruptions are increased by heating or Cooling the Mints. By Rachel Cutler and Emma Smith

Introduction: Although there have been numerous experiments regarding the temperature of the soda versus the height of the explosion; we have found that there are no apparent results of the effect of the temperature of the Mentos in regards to the height of the explosion. 1Many people have conducted these experiments because it is fun to watch, and because it is quite interesting as to what makes the two create such a fantastic reaction. Most scientists say that it is the gum arabic that reacts with the soda and produces the desired result2. There may have been experiments done regarding this, but we have not found any results of those experiments. This had an effect on our experiment because we had no previous results to compare our findings to. But in a way this was also good, because it was as if we were the first ones who were discovering the effect temperature-changed Mentos had on Diet Pepsi. The reaction between Coke and Mentos usually produces a good reaction3, and although our experiment was modified it nonetheless produced good results. Summary: We wanted to see if the Temperature of the Mentos affected the height of the explosion when dropped into a bottle of diet Pepsi. We froze Mentos, heated them up, and kept them at room temperature to test the effects of each one, and then measured the height of the explosion of the diet Coke. Experimental Section: Our goal was to find which temperature most affected the soda, and would therefore create the biggest explosion. To do that we picked three different temperature areas to focus on: coldest, room temperature, and the hottest. We put one package of Mentos in a freezer, another sitting out in the room undisturbed, and another we wrapped in tinfoil and put on a hot plate. We then chose ten Mentos and put them into a graduated cylinder on top of an open bottle of Pepsi. I walked away after I opened the bottle of Pepsi, and Rachel ran away immediately after she dropped the Mentos into Coke. By doing this I was able to get the first look at how the explosion went, and then both Rachel and I were able to concentrate together once she ran away. We didn’t use any kind of nozzle because we were focusing on finding how the temperature of the Mentos affects the height of the explosion. We considered our negative control to be the neutral Mentos, which did produce a result, but not the one that we most desired. Our positive controls were the Mentos we either heated or froze. Through this we were able to compare the results of the positive controls to the results of our negative control. Overall, our experiment was one based not on design, but rather upon finding an answer through an experiment that produced results. Experimental Procedure: Materials: ~at least 3 bottle of Diet Pepsi ~at least 3 packages of Mentos ~2 meter- sticks ~a bin to catch all the sodas if you are conducting the experiment inside 1

http://chemistry.org/education/chemmatters.html http://en. wikipedia.org/wiki/Diet_Coke_and_Mentos_eruption#Explanation. 3 http://en.wikipedia.org/wiki/Mentos#Mentos_and_soft_drink_reaction 2

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1. 2.

3. 4.

5.

~towels to clean up the surrounding area, again if you are conducting the experiment inside ~tinfoil ~a hot plate ~a freezer ~a thermometer ~a graduated cylinder which you’ll put your Mentos in Procedure: Gather all the materials that is necessary for the experiment at hand Put 10 Mentos in a piece of tinfoil in a freezer, and keep them there as long as possible. Put another 10 in another piece of tinfoil and put on the hot plate; remember to keep checking the Mentos so they don’t melt, or worse, start a fire. And finally, keep another 10 Mentos out to absorb the surrounding temperature. Set up your experimentation area; with your soda in the bucket, and at least 2 meter sticks tied or taped together and put the 10 Mentos in the graduated cylinder. Have one person open the bottle of Coke, and the other person line the graduated cylinder up with the opening of the bottle. After the person who opens the bottle up is done with their job they should move in front of the area so they can see how high the explosion is. The other person should drop the Mentos into the bottle and run away as fast as possible so they don’t get wet. Continue the experiment with the other two packages of Mentos and soda bottles, and do as many experiments as possible so as to increase the validity of your results. Record your results as you go along in your experiment. Conclusion: Through this experiment we were able to realize and discover the fact the temperature of the Mentos does have an effect upon the height of the explosion. The Mentos that were heated to a degree of 313K reached a height of about two meters, or 200 centimeters. The Mentos that were kept at room temperature were about 303K; reaching a height of about 30 centimeters. Our biggest explosion by far was that produced by the Mentos that were frozen to a degree of 263K, and the force that the explosion hit the towel with was so great that it sprayed outwards. Because of that, we can only roughly judge that the explosion reached a height of 350 centimeters. Our results showed us that the temperature of the Mentos really does have an effect on the height of the explosion. Although our experiment did produce valid results there were a few errors along the way. Those included not all the Mentos falling into the Pepsi, and therefore not producing the full effect. We were also not completely exact in judging the height of the explosion, most of the time we had to make a quick estimate of where the peak of the eruption was. To make our results more valid we should have done more tests, which would have given us more support in the deduction that the more extreme the temperature the greater the eruption will be and more validity regarded the results we made. Overall, we were able to discover what we had initially wanted to find out; the temperature of the Mentos does have an effect upon the height of the eruption of the soda. However, to make our results more valid and better understood we should have done more tests; we also should have done more experiments because not all of the Mentos were dropped into the Pepsi which made the eruption results differ. However, we can concur that height is affected by temperature, and we are positive that if future tests were done regarding this, the scientists or whoever is conducting the experiment will find the same results that we found.

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8

0

50

100

150

Height of Explostion (Centimeters) 200

250

300

350

236K

Temperature (Kelvin)

303K

313K

The Effects of the Different Temperatures of Mentos in Diet Coke


Sustained Mentos Eruptions. Creation of a 40 Second Mentos Eruption by Mike Moalli and Steffi Marsh

Summary We tested coated mentos to see which coating would create the longest diet coke and mentos eruption. After testing our control, oil, sugar, molasses, and honey, we concluded that honey made the longest eruption of 40.28 seconds.

Introduction There is little to no information about how to delay the mentos reaction or how to make a prolonged mentos eruption. However it is believe that what causes the mentos and diet coke reaction is not a chemical reaction but a physical one. The gellan gum and gum arabic in the mentos dissolve and breaks the surface tension. This disturbs the water connection, so that it takes less work to expand and form new bubblesš. Each mentos candy has thousands of tiny pores all over its surface. These tiny pores function as nucleation sites for carbon dioxide bubbles to form. When the mentos enter the soda, bubbles form all over their surface. They quickly sink to the bottom, causing carbon dioxide to be released by the carbonated liquid with which they come into contact along the way. The sudden increase in pressure pushes liquid up and out of the bottle².

Experimental Section Our original experiment was to design a delayed mentos eruption. In order to do this we decided to coat the mentos in a variety of different substances to get the desired affect. Some of these substances including: honey, oil, molasses, sugar, salt, and others. We would coat three mentos in each of the substances and drop them into a small twelve ounce bottle of diet coke and then time how long the reaction was delayed compared to the control (three mentos that were not covered in any substances). After completing this we found that none of the substance had any significant delay in the reaction, however we notice that different substances gave a longer reaction. Using this newfound data we 9


retested some of the substances and timed how long each reaction was. After completing this we found that honey worked the best for creating a longer reaction.

Results Effects of Coatings on Mentos

reaction time (in seconds)

45 40 35 30 25 20 15 10 5 0

control oil sugar molasses honey control

oil

sugar

molasses

honey

types of coatings

control oil sugar molasses honey

7.17 7.89 10.32 30.18 40.28

Conclusion After conducting our experiments we have come to the conclusion that honey coated mentos work the best for a prolonged mentos and diet coke reaction. However our original experiment was inconclusive in finding a substance that delayed the mentos reaction. But in the progress of trying to find a substance that would delay the mentos reaction we found that some substance prolonged the mentos reaction by as much as 30 seconds. Some follow up experiment may include: the amount of honey used in covering the mento, break down honey into pure substance and seeing which substance in the honey is the main component in prolonging the reaction, and using different kinds of honey. Although we did not achieve our intended goal of making a delayed mento reaction, we believe that we have found something more useful and more fun overall.

1. a. b. c. d. e.

Materials 2 ounces of the following at room temperature: Sugar Molasses Honey Oil Water 10


2. 3. 4. 5. 6. 7. 8. 9.

5 pieces of string each about 15 centimeters long 5 two liter bottles of diet coke At least 50 regular mint mentos Tongs Drill (to make a holes through the mentos) Pencil or pen and paper (to record results) Stop watch Towel

Experimental Procedure 1. Take all of the mentos and drill holes though them. 2. Put them in groups of ten and tie ten mentos on each of the five strings. Make sure they are tied close together so there is room to hold the string before you drop it into the bottle. 3. Make sure to do this experiment outside where it’s okay to make a mess of diet coke and mentos. 4. The first test will be the control so there is no need to coat this sting of mentos in anything. 5. Have your stopwatch ready because the string of mentos needs to be dropped into the bottle as soon as it is opened (to keep the carbon in) and the explosion will begin as soon as the string is dropped. Remember, you are testing how long the entire explosion takes to compare it to the other coated mentos. 6. Open the bottle of diet coke and immediately drop the string of mentos into it. Stand clear at least three feet to prevent being soaked in diet coke. 7. Once the diet coke reaction has stopped fizzing out the top, record your results. 8. This time you’re going to be testing the honey. Dip the string of mentos into the honey and use the tongs to make sure there’s a nice thick coat of honey each of the mentos. Make sure to use a new bottle of diet coke and a new string of mentos each time you perform a trial because if either of them have been used for a previous trial, there will be no diet coke eruption. 9. Now repeat steps 4-7 with molasses and then repeat the same steps with oil. Then skip to step 10. 10. When you’ve finished testing the control, honey, molasses, and oil, now test the sugar. Quickly dip your last string of mentos into the water before you coat it in the sugar. Again, repeat steps 4-7 with the sugar mentos, and then skip onto step 11. 11. Once all the experiments are completed, use the towel to clean up any mess if needed. Don’t forget to recycle the diet coke bottles.

References 1. http://en.wikipedia.org/wiki/Diet_coke_and_mentos 2. http://www.stevespanglerscience.com/experiment/00000109

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Remote Control Mentos Eruption by Paul Mulligan and Jared Searles Manuscript in preparation. The Effect of Nozzle Size on the Height of Mentos Eruptions. Discovery of a method for thin, sustained eruptions by Aaron Davis and Travis Dillon The purpose of this experiment is to see if we use different nozzle sizes if it would affect the size of the eruption of diet coke when mentos is put into it. We believed that the smaller nozzle size we used the higher the eruption would go. When we conducted our experiment we were correct. When we placed 3 mentos into a 12 ounce diet coke bottle with no cap the eruption only went 8 centimeters high. Except when we put 3 mentos into a 12 ounce diet coke bottle with a 3 millimeter nozzle that the eruption went over 2 meters. We also tried with a nozzle size of 11 millimeters but the height of the eruption only went 61 centimeters. When we conducted studies on the height of diet coke eruptions when mentos is put into the coke we found out that the smaller nozzle size the higher the eruption and the longer the eruption will last. With a larger nozzle size the eruption will not go as high nor as will the eruption last as long. In our experiment we conduct an experimental procedure that focused on how different nozzle sizes of diet cokes will affect the size of eruption when mentos is put into the diet coke. We used 3 diet cokes with no caps, 3 diet cokes with 3 millimeter nozzle, and 3 diet cokes with 11 millimeter nozzle. We placed 3 mentos in each diet coke and measure the height of the eruption using meter sticks. In our experiment we found out that the smaller nozzle size the higher the eruption will go. We came to this conclusion because when we used a nozzle size of 3 millimeters we got our highest eruption of over 2 meters. The average of the eruption with a 3 millimeter nozzle was over 2 meters. When we did not use a cap at all the average height of the eruption was 6.7 centimeters, the lowest eruption we had. When we used a middle size nozzle of 11 millimeters we got a larger eruption then using no cap but a smaller eruption when we used a 3 millimeter nozzle.

1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11.

Procedure: Gather materials Take 3 12 ounce bottles of diet coke and open cap Place 3 mentos in each of the three bottles Measure the height of the eruption by using a meter stick Record the data you collected Repeat step 2 Take a drill and drill a 11 millimeter hole into all three caps Repeat steps 3, 4 and 5 Repeat step 2 Take a drill and drill a 3 millimeter hole into all three caps Repeat steps 3,4, and 5 http://eepybird.com/science.html http://eepybird.com/How%20To%20Do%20It%20Yourself!.pdf 12


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NOZZLE DESIGNS CREATE SPRAY EFFECTS FOR MENTOS ERUPTIONS Taylor Smith and Rosie Steffen

Introduction: “The Mentos and Diet Coke Experiment” is caused when Mentos mint candies are dropped into a bottle of a carbonated substance. The result is a jet of soda which spews from the neck of the bottle. The reaction is due to the rapid expanding of carbon dioxide bubbles on the surface of the candy. i

Experiment: In order to create a Mentos eruption, one releases a number of Mentos mint candies into a

bottle of Diet Coke. When the two elements of the experiment combine, they result in an explosion consisting of the carbon dioxide “fizz” of the Diet Coke. In this particular experiment, holes of varying sizes and patterns were drilled into the caps of the Diet Coke bottles prior to the release of the Mentos, thus causing the height and spray patterns to also vary. To enhance the height of the results, the holes drilled in the bottle caps must be smaller. When designing the experiment, drilling holes in a circular formation, created a fountain effect with the “fizz,” or by arranging the holes in a line formation, the “fizz” erupts in a similar fashion. In order to create a more horizontal effect of the spray, the holes should be drilled at an angle, pointing as much towards the opposite side of the bottle as possible. The holes cannot be drilled on the side of the cap itself; because of they would directly interfere with the cap’s ability to hold onto the bottle, thus resulting with projectile qualities. In this particular experiment, the hole which created the highest and longest lasting spray effect was a single hole in the center of the cap drilled with a 4mm drill bit.

Conclusion: In this experiment, the best results were the single, 4mm sized

hole because the carbonation was so concentrated to a single are and therefore resulted in the highest height (6.09m or 20 ft.) and the hole which was drilled at an 8mm resulted in the lowest height (.9144m or 3ft.). This experiment could be modified for better results by applying further variations to the nozzle designs to better Caps with 8mm holes. shape the eruption and thus increasing the number of eruptions in order to achieve the desired effect. Caps with 4mm holes.

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Experiment Procedure:

Gather materials: 1 two liter bottle of Diet Coke (otherwise unflavored for best results), 1 package of at least ten mint Mentos, 12 cm of dental floss (or other string), a 5 cm (at least) thick piece of plywood, a 5cm roofing nail, a 4mm and 8mm drill bit, a power drill and two or three meter sticks. Step 1: Using the roofing nail, score ten Mentos by slightly applying pressure to the middle of the Mentos candy. Create a depression in the candy so that the drill bit will not slip off the Mentos when drilling. Do this for all ten candies. Step 2: Set up your drilling station by laying the plywood down. Ready your ten scored Mentos and begin to drill through them. Start by applying slight pressure downward on the candy while slowly drilling and only slightly increasing the drilling speed once the hard sugar coating is broken though. The speed increase after the coating, is necessary because the inside of the candy is gummy and a faster speed is needed to work through it. The candy might crack in half, do not use these because they could break apart during the experiment and cause a premature eruption. Repeat this process for all ten Mentos. Step 3: Drill the desired design in the bottle caps. It is better to collect other bottle caps and drill those because if the caps are removed from the test bottles, the carbonation in the soda will escape. Drill the desired designs in both diameters but on separate caps so that the height will vary. Remember that fewer holes in the caps create a greater concentration and therefore create the best results. Step 4: String your Mentos on the dental floss. Once you have completed that, take the string and thread it through one of the central holes in the drilled bottle caps. Step 5: Stand the three meter sticks end to end, vertically. Secure them as you see fit (duct tape is the best). Attach them to the Diet Coke bottle in the same fashion so that they will record the height of the eruption. Step 6: Open your test bottle and quickly remove enough soda so that when you screw on the drilled cap, holding the string of Mentos, the soda will not touch the candy resulting in a premature eruption. Once the drilled cap is securely on, hold the string of Mentos vertically and make sure it will not get stuck anywhere on the cap when it is released. Step 7: Before letting go of your sting, have a partner stand nearby to take pictures of the eruptions because this is a more accurate method of recording the eruption height. Step 8: Release your string and run!

(Repeat the procedure as many times as you wish, try varying the number of Mentos to achieve different heights.)

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The Effect of Soda Type on the Height of Mentos Eruptions By Ethan Shore and Zack Brown Summary: We tested the effect of different soda types on the height of mentos based eruptions in 2 liter soda bottles. We did 2 trials for each soda; Diet coke had explosions of .6 and 1.1m. Coke explosions of .1 and .15m . Sprite had explosions of .45 and .57m. Sprite zero had explosions of 1.1 and .95m. Sprite zero had the highest average explosion, with an average of 1.025m. Introduction: While many people have tried the Diet Coke and Mentos eruption experiment before, not many people have attempted to test different soda types with Mentos. However, the phenomenon was started by Steve Spangler, a science teacher, which got an explosion with Diet Coke and Mentos reaching 5.5 meters¹. He determined that as the rather heavy candy falls to the bottom of the bottle, carbon dioxide is released and the suddenly increased pressure pushes the liquid out of the bottle¹. One science class also attempted testing 44 different soda types on Mentos eruptions². Experimental: We tested each soda by opening the each bottle of soda, and then placing 5 Mentos inside the soda bottle, and then waited for the eruption. There were meter sticks behind the soda, so we could measure each eruption. We used 5 Mentos for each trial. Results:

The Effect of Mentos on Different Soda 120

Height

100 80

Trial 1

60

Trial 2

40 20 0 Diet Coke

Coke

Sprite Zero

Sprite

Soda

Conclusion: Based on our results, Sprite Zero causes the highest Mentos eruption with an average eruption of 1.025m. Diet Coke had the second largest explosion with an average of .85m. Sprite had the 3rd largest explosion, with an average of .51m. And Coke had the smallest average explosion, with an average of .125m. 17


This data was not 100% conclusive. During some of our trials, it was not clear whether all 5 Mentos made it into the bottle before the explosion occurred. Another factor lessening the conclusiveness of the results is the fact that after we dropped the Mentos in, we had to move out of the way very quickly. Sometimes, my hand partially hit an explosion, perhaps causing the height to drop. The results of this experiment were somewhat valid. Experimental Procedure Step 1: Gather 2, 2 liter bottles of Sprite, Diet Coke, Coke, and Sprite Zero. Step 2: Gather 40 Mentos, and a test tube (small enough for Mentos to fit in, large enough for them to fall out). Step 3: Take the plastic bin from the front of Dr. B’s room, and place it at one of the back tables. Step 4: Tie 2 meters sticks together behind it, making sure that the sticks are straight. Step 5: Place a bottle of Diet Coke in the bin. Step 6: Place 5 Mentos in the test tube. Step 7: Open the bottle. Step 8: Drop the Mentos in the bottle. Step 9: Record the height of the explosion in your data. Step 10: Repeat steps 5-10 for Diet Coke once more, and each other soda twice more. References: šhttp://sciencecentered.blogspot.com/2007/04/mentos-and-diet-coke-geysir.html ²http://www.geysertube.com/blog/

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How the Coatings of Mentos affects the size of the Mentos Eruption by Carly Clark and Jenn Agamie Introduction: For our experiment we decided to test the different effects of mentos coatings on diet coke to see the different heights of eruptions. To test our theory we used a control, which was the regularly coated mentos, mentos without any coating, and mentos drenched in dish soap. After three trials we were able to clearly see that the regularly coated mentos had the best eruption by far. Summary: Throughout our experiment we concluded that the non-coated mentos had the worst height. The average height in centimeters after three trials was only 33.33 cm. This shows that there was hardly any eruption at all. The mentos soaked in dish soap averaged to be 58.33 cm, which is better than the non-coated but still not superb. Finally, we were able to test the regular mentos and received an average height of 230 cm. We made sure to use exactly ten mentos per liter of diet coke so that we had a constant throughout our experiment. Experimental Section: The design of our experiment was to see what actually made the mentos in the diet coke to erupt. After several ideas were tossed around we decided to see if the coating had anything to do with the eruptions. In order to test this idea we de-coated ten mentos and covered ten more in Dial dish soap. Then we gathered ten more mentos and left them with their regular coating. Instead of stringing the mentos onto a wire and dropping them into the diet coke bottles we decided to place all ten of them into a graduated cylinder and hold a thin piece of paper over the opening. We flipped the graduated cylinder upside down so that the opening covered with paper was lined up to the top of the diet coke bottle. We tried to let as little carbonation out of the bottle as possible, so that there was more of a reaction. Procedure: 1. First, we gathered our materials, which consisted of a graduated cylinder, 3 liters of diet coke, and 2 packages of mentos. We also used dial dish soap, a beaker, and thin pieces of paper, two-meter sticks, and a bucket. 2. Then we made three piles of ten mentos. One set we covered in soap, then next set was regular, and the third we soaked in a beaker full of hot water so that the coating would dissolve. 3. After the mentos were ready, we placed one liter of diet coke in the bucket so that when the eruption occurred soda wasn’t sprayed everywhere. 4. Next, we taped two-meter sticks together and tied them around the diet coke bottle so that we were able to see the height of the eruption. 5. Then one of us held the graduated cylinder upside down above the top of the bottle. While the other person unscrewed the cap. 6. As soon as the cap was unscrewed the person holding the graduated cylinder moved the paper and released the mentos into the diet coke. 7. We made sure to stand far enough from the eruption so that we wouldn’t get soaked in soda, but close enough to see the height of the eruption. 8. Once each different type of mentos underwent the experiment we recorded our data into a table. 9. We performed the experiment two more times. Each time recording our data to make sure the height was accurate. We then averaged the height of the different mentos to see the results as one. 19


10. Once each trial was through, we cleaned our station and compared our results to our hypothesis. Conclusion: After having tested our experiment many times we came to a conclusion that the mentos with the regular coating had by far the best eruption. While it averaged in 230 cm the other two only went up to 58.33cm (soap), and 33.33 cm (non-coated). As we thought, there is something in the coating of the mentos that effects the eruption. During our experiment we were very much in awe to see that the two mentos that were changed had such a low height.

References:

1.”Mentos Geyser.” Making Science Fun. Feb.10, 2008. http://www.stevespanglerscience.com/experiment00000109. 2. “Diet Coke and Mentos Eruption.” Wikipedia, the Free Encyclopedia.Feb. 10,2008 http://en.wikipedia.org/wiki/Mentos-eruption. 3. ‘How to Make a Soda Bottle Volcano.” Extreme Diet Coke and Mentos Experiment, Wikihow. Feb.11, 2008 http://www.wikihow.com/make-a-soda-bottle-volcano.

The Effects of Different Mentos Coatings in Diet Coke

300

200

Series1

150

Series2 Series3

100 50 Averages

Regular Coated Mentos

Non-Coated Mentos

0 Soap mentos

Height(cm)

250

Different Coatings

20


Warm Soda has a dramatic effect on the Height of a Mentos Eruption by Justin Husted While numerous experiments have been done with the coke mentos eruption, sometimes called the coke mentos geyser or rocket, very few have tried testing the effects of the temperature of soda before adding the mentos. Some brave experimenters have come to the conclusion that the reaction rate appears to double for every 10 degrees Celsius that you heat the diet coke. Similarly for every 10 degrees that the soda is cooled (or frozen) the reaction power and height is cut in half. 4 Also according to www.stevespangler- science.com, the temperature of the soda greatly affects how much force and height the geyser of soda fizz will shoot up to.5 My goal is to duplicate their experiments in an attempt to find if the temperature of the diet coke actually affects the height of the mentos eruption. The Experiment: By submerging bottles of coke into different water temperatures, we can safely control the temperature of the soda inside. The three temperatures being used in this experiment are cold, (262 K) room temperature (298 K) and warm diet coke (approximately 308 degrees K). Using eight mentos in each bottle, they will be set up to erupt and see which yields the biggest eruption. Summary of findings: The results of the experiment were clear and as expected. The coldest coda resulted in the small and shortest eruption of diet coke. The room temperature soda had expected results and was a relative increase from the cool soda. The warm diet coke’s results sky-rocketed. Of the two warm test trials, both blast the coke into the air with a large amount of force, resulting in an average height more than double what the room temperature soda achieved. Conclusion: At the conclusion of this experiment I found that, as expected, the warmest soda temperature produced the biggest results of the three. The coldest soda temperature barely erupted out of the bottle. The cold soda was submerged in water measured at 263 degrees Kelvin. After putting in eight mentos, the following eruption resulted in about 20 centimeters of height. The next largest was the soda that was left in the classroom for two days to ensure it was the average temperature of the room. The temperature was measured at 298 degrees Kelvin. The resulting eruption was approximately one meter exactly. (100 centimeters). The final trial was of the warmest soda was that which was heated in water measured at 308 degrees Kelvin. The resulting reaction resulted in an eruption of 300 centimeters (three meters). By the results of the data, it is easily safe to conclude that the warmer the diet coke temperature, the more height the eruption gained.

Experimental Procedure: The following steps will lead to the exact duplicate of the above experiment. 4

Username: “Labmonkey� Yahooanswers.com January 10th, 2008

5

www.stevespanglerscience.com, mentos and soda temperature.

21


1) Obtain materials, needed is: three 2 liter bottles of diet coke, exactly 24 mentos candies, a thermometer, meter sticks, and glass cylinder containers to house hot and cold water. 2) Submerge one sealed bottle of diet coke into a cylinder of cold water, measured at 262 degrees Kelvin. Leave in for at least ten-twenty minutes. 3) Submerge a second bottle into warm water. Use the thermometer to measure the temperature of the water to 308 degrees Kelvin. Leave in for ten-twenty minutes. 4) The third and final bottle should be left in normal room temperature conditions (approx. 298 degrees Kelvin) 5) Set up a measuring system of at least two meters sticks in a container to catch the spraying coke. Tape or string should be used to attach two sticks together. 6) Using a graduated cylinder to house eight mentos, un-attach cap of the first bottle and drop mentos inside, stand back, observe and measure height using meter sticks. 7) Repeat step six for the remaining two bottles of diet coke. Use exactly eight mentos each time and record each height in a table for future reference. 8) Graph and conclude data.

22


Creating a “Misting Mentos Eruption” By Gabriella Necklas and Kiersten Wall

Summary: For our experiment we tested how the shape of the opening that the soda sprays through affects the height of the geyser. Our goal was to determine which nozzle created the greatest height. From our experiment we were able to conclude that the smaller the hole the higher the geyser created. We were also able to see that a circular shape works better than a slit in the cap does. Introduction: In the field of Mentos eruptions there is still some debate over how the reaction occurs. However, there is one relatively accepted reason for the reaction. “When you drop the Mentos into the soda, the gelatin and gum arabic from the dissolving candy break the surface tension. This disrupts the water mesh, so that it takes less work to expand and form new bubbles. Each Mentos candy has thousands of tiny pits all over the surface. These tiny pits are called nucleation sites - perfect places for carbon dioxide bubbles to form. As soon as the Mentos hit the soda, bubbles form all over the surface of the candy.” ii It is also well noted that a substance under pressure that is forced through a small hole will go higher than the same substance through a substantially larger hole. This is how we came to the hypothesis that our small hole would produce the largest geyser. Experimental Section: For our experiment we conducted two trials. Each trial followed the same procedure, our goal was to try and get the most accurate results possible. We dilled a hole into the center of each mento and then strung 10 mentos for each nozzle type. We then pulled the other end of the string through the nozzle so that the mentos would hang below the nozzle and into the bottle while we had about a two inch portion of string to hold onto until the designated time for eruption. We also attached two meters end to end and staked them into the ground behind our soda bottles in order to measure our eruptions. Once all of these preliminary steps were taken care of we screwed on the nozzle that was being tested and let go of the string in order to release the mentos into the Diet Coke. Results Section: 23


Nozzle Type Trial 1 Trial 2 Control 1 meter 1.2 meters Small Hole .7 meters About 3.5 meters * Straw .5 meters 2 meters Small Slit .2 meters 1.5 meters Measurements have been rounded. *Our measuring device only went up to two meters, for this measurement we had to estimate its final height. Our first trial is significantly different than our second trial for all of our experimental nozzles because of a malfunction we had with our release cord. For our second trial we were able to fix the problem and our results are much larger because of it. Conclusion: Our results conclusivly show that the small hole is the optimum nozzle size to produce a large geyser. The small hole went 1.5 meters higher than its closest rival, the straw. Even though the straw and the small hole’s openings had the same diameter they both had drastically different results, we believe that the length of the straw affected the height of the geyser. Also while the small slit did manage to go higher than the control, by only .3 meters, we were able to see that at a certain point the hole becomes too small for the geyser and it has the affect of creating a much shorter eruption. We noticed during our trial of the small slit that more of the soda was coming out in a mist like fashion creating a much shorter and less impressive eruption. For follow up experiments it would be a good idea to try nozzles of different lengths. For instance cutting a straw into three different lengths in order to see if it was really the length of the straw that caused it to create a shorter geyser than the small hole. Another possible follow up experiment would be to have holes that gradually increase in diameter to check if the small slit really was too small and if the small hole really is the optimum size. Procedure: 1. Gather 8 two liter bottles of Diet Coke, 4 boxes of Mentos, string, a drill, a straw, and a pastry nozzle used to make ribbon like lines. 2. Drill a Ÿ inch hole into a soda cap, this will be the small hole nozzle. 3. Drill another Ÿ inch hole into another soda cap and insert the straw into the hole so that when the cap is screwed onto the bottle the strawl will stick up on the outside. This will be the straw nozzle 4. Now drill a hole into another cap that is large enough to fit the pastry nozzle. Then insert the pastry nozzle into the hole so that when the cap is screwed onto the bottle the nozzle is on the outside. Hot glue the pastry nozzle into place so that no liquid can escape. This will be the small slit nozzle 5. Now drill a hole into the center of 80 Mentos, this will be enough for both trials on each nozzle. 6. Tape two meter sticks end to end and stake them into the ground so as to measure the eruptions. 7. Place an open Diet Coke infront of the meter sticks. 8. String 10 drilled Mentos and hold them so that only the bottom two Mentos are in the neck of the bottle. Count down from three and drop the Mentos into the soda. Record the eruption, this will be your control. 9. Repeat step 8 for the second trial of the control. 10. Now string another 10 Mentos. Run the top of the string through the small hole and screw the small hole nozzle with the mentos dangling beneath it onto a new Diet Coke bottle, make sure that the Mentos will not touch the diet coke, you may need to pour out some soda. Place the ready bottle infront of the 24


11. 12.

13. 14.

15. 16.

meter sticks and count down from three then drop the Mentos into the soda and record the eruption.This will be your small hole trial. Repeat step 10 for the second trial of the small hole. Now string another 10 Mentos and run the top of that string through the straw nozzle. Screw the nozzle onto a new Diet Coke bottle so that the mentos hang below it, make sure they do not touch the soda, you may need to pour some soda out. Place the readied bottle infront of the meter sticks and count down from three, then drop the mentos into the soda and record the height. This will be your straw trial Repeat step 12 for trial two of the straw nozzle. String another 10 Mentos and run the top of the string through the small slit nozzle. Screw the small slit nozzle onto a new bottle of Diet Coke so that the mentos hang inside the bottle, make sure they do not touch the soda, you may need to pour some soda out. Place the bottle infront of the meter sticks, count down from three and let the Mentos fall into the soda. Record the geyser, this will be your small slit nozzle trial Repeat step 14 for trial two of the small slit. Clean up the workspace. Gabriella Necklas and Kierstin Wall

i

“Diet Coke and Mentos Eruption,� http://en.wikipedia.org/wiki/Diet_Coke_and_Mentos_eruption

ii

http://www.stevespanglerscience.com/experiment/00000109

25


The Guilford Journal Of Chemistry Volume 2 October 1, 2008 This is our second issue dedicated to the investigation of the well-known Mentos Eruption.


The Guilford Journal of Chemistry Dr. Harry Brielmann, Editor

The premier, state of the art venue for publication and broad dissemination of first-rate, fundamental research in all of chemistry and Mentos Research. Volume 2

Table of Contents Featured Paper #1 A Four-Way Remotely Controlled Simultaneous Release Mechanism for Diet Coke and Mentos Eruptions by Ryan Johnson and Will Graziano Featured Paper #2: Diet Pepsi – Not Diet Coke - Results in the Highest Mentos Eruption When Compared to Other Diet Carbonated Drinks By Angelise Musterer and Lindsay Ruotolo Featured Paper #3: Cinnamon Mentos Eruptions are 20% Higher than Mint Mentos Eruptions By Allison Federici and Jess LaChance A Time Delayed Diet Coke and Mentos Experiment By Mike Amento and Scott Leone Volumes Effect on a Mentos Explosion By Kaitlyn Earles and Megan Graham Six Meter Coke and Mentos Eruption Achieved by Heating the Bottle By Mary Melillo and Artem Guryanov Eruptions Caused by Mentos Increase with Smaller Nozzle Sizes By Holly Aery and Adam Sierzputowski

2


Comparable Reaction of Diet Coke as Opposed to JOLT Energy By Dylan Klett and Trevor How the Amount of Mentos Affects the Height of the Eruption By Matt Feldman and Alex Monte Communications Discovery of the Worlds Longest Mentos Eruption: One Hour and Forty Minutes.

By Sam Taylor and Will Schaffer

Drilling a 5 mm Hole in a Mentos Candy Results in a 20% Increase in Eruption Height.

By Nick Hill and Kyle Gaboury

Cold Soda Increases the Height of a Mentos Eruption

By Andrea Cawley, Morgan Ehrler, and Pam Salmeron

Mentos Sliced in Half will Double the Height of a Mentos Eruption Karo Syrup Quenches the Mentos Eruption Serendipitous creation of a Mentos Rocket

By Emily’s Ring and Kipness

By Kelsey Robins and Laura Turcio By Alex Jagielski and Eric Hedberg.

.

3


Introduction to the second issue of the Guilford Journal of Chemistry Like the first volume,1 this second volume of The Guilford Journal of Chemistry includes groundbreaking discoveries and applications of the mentos eruption. Prior to the publication of the first volume of this Journal, numerous theories have been purported to explain the science behind the Mentos Eruption2. These sources have been analyzed by numerous students, and with the single exception of the well known Mythbusters investigation3, no significant experiments had been documented, a deplorable condition considering the popularity of this phenomen. The first issue of this Journal documents the first publication of peer-reviewed research in the Mentos Eruption. Several exciting discoveries were made, including the bizarre observation by Cutler and Smith4 that both cold and warm mentos will increase the height of a mentos compared to a standard room temperature eruption. Other studies created long sustained eruptions,5 and numerous special effects were demonstrated, including a remote-controlled eruption device by Mulligan and Searles.6 All of these discoveries were tested in this second volume, and numerous new discoveries were found. Numerous investigators designed experiments to confirm (or invalidate) the unique results of Cutler and Smith. It was confirmed by most but not all of the investigators that either heating or cooling a mentos will increase the height of an eruption. A careful, convincing study is badly needed to confirm or reject this observation. This also led to a accidental discovery by Taylor and Schaffer7: A melted mentos will erupt at a very slow, sustained rate, continuing for nearly two hours. Two careful studies refuted common mentos assumptions. It is widely assumed that mint mentos produce the highest eruptions. In fact Federici and LaChance8 found that cinnamon mentos will create an eruption that is 20% higher than mint mentos. Perhaps one of the most widely assumed conclusions is that diet coke creates the highest eruptions of all carbonated beverages. However, Musterer and Ruotolo9 found that Diet Pepsi is the soda of choice, creating an eruption that is, amazingly, over 100% higher relative to diet coke. This important discovery needs independent confirmation. A creative study by Earles and Graham10 suggests that the power of an eruption should not be measured by eruption height, but rather by the volume of the eruption. Interestingly, the remaining volume of soda for a variety of soda sizes was constant, suggesting that there is a fixed relationship between soda size and eruption volume. One of the most surprising results concerns the work of Kipness and Ring,11 who found that a mentos cleanly sliced in half erupts higher than a whole mentos. A similar conclusion was determined by Hill and Gaboury,12 who determined that a drilled mentos erupts higher than a normal mentos. What is this due to? It is our hope that the researchers of Volume Three of the Guilford Journal of Chemistry can sort this out.

4


Among numerous others, two other studies merit mentioning here. A study by Robins and Turcio13 designed to use the power of the mentos to simulate a volcanic eruption instead accidentally discovered that the reaction can be entirely quenched by an additive. However, it was never finally determined if the effect is due to corn syrup or red food dye. Finally, in a featured paper, one of the most spectacular eruption was performed by Johnson and Graziano,14 who created a remote controlled four-way simultaneous mentos eruption. Researchers who are interested in special effects techniques and remote insertion methods should read the details concerning these methods. And in an accidental discovery certain to create numerous follow-up studies, Jagielski and Hedberg created and launched a Mentos Rocket.15

In summary, despite over twenty published articles in the first two Journals, two of the fundamental theories regarding this eruption have yet to be investigated, including: 1. Is gum Arabic the key group of substances in the Mentos Eruption, or is that simply a myth? 2. What is up with the nucleation sites? Many experiments have indicated that the surface character of a mentos is critical to the height of an eruption, but the actual surface shape (topology) has never been photographed, either alone or during the eruption, although time release photography has come close. This key theory needs to be tested. As it stands now, Guilford High School is, to our knowledge, the only place where the Mentos Eruption is being carefully studied leading to published results. That being the case, there is every reason to believe that significant discoveries will continue to be made in this wide open field of research. 1. Guilford Journal of Chemistry, Volume 1 (2007), H. Brielmann, editor. Available online at http://chemistryadventure.com/Documents/guilford%20journal%20of%20chemistry%20volume%201.pd f 2. For an informative historical account of the Mentos Eruption, Speve Spangler’s website is recommended: http://www.stevespanglerscience.com/experiment/00000109. Note that the original Letterman Show Mentos Eruption may be viewed on the internet at http://www.chem.uic.edu/marek/letterman0/video/mentos.htm. For accounts of Mentos-like eruptions dating back to the 1980’s, see: Marek at http://www.rimmkaufman.com/rkgblog/2007/12/21/stevespangler/. 3. The mythbusters investigation of the mentos eruption may be found at http://dsc.discovery.com/videos/mythbusters-diet-coke-and-mentos.html. A fairly lame christmas themed investigation called “Merry Blastmus can be viewed at http://dsc.discovery.com/videos/mythbusters-merry-blastmus.html. And an ultra-slow motion mythbusters view of the eruption is at http://dsc.discovery.com/videos/time-warp-soda-fountain.html . 4. Rachel Cutler and Emma Smith, Guilford Journal of Chemistry, Volume 1, Pages 6-12 (2007). 5. For example, see Steffi Marsh and Taylor Smith, Guilford Journal of Chemistry, Volume 1, Pages 1316 (2007). 6. Although details are unavailable, see Paul Mulligan and Jared Searles, Guilford Journal of Chemistry, Volume 1, Page 12 (2007) 7. Sam Taylor and Will Schaffer, Guilford Journal of Chemistry, Volume 2, Page 38 (2008). 8. Allison Federici and Jess LaChance, Guilford Journal of Chemistry, Volume 2, Pages 15-16 (2008). 9. Angelise Musterer and Lindsay Ruotolo, Guilford Journal of Chemistry, Volume 2, Pages 12-14 (2008). 5


10. Kaitlyn Earles and Megan Graham, Guilford Journal of Chemistry, Volume 2, Pages 21-22 (2008). 11. Emilies Kipness and Ring, Guilford Journal of Chemistry, Volume 2, Page 38 (2008). 12. Nick Hill and Kyle Gaboury, Guilford Journal of Chemistry, Volume 2, Page 38 (2008). 13. Kelsey Robins and Laura Turcio, Guilford Journal of Chemistry, Volume 2, Page 38 (2008). 14. Ryan Johnson and Will Graziano, Guilford Journal of Chemistry, Volume 2, Pages 9-11 (2008). 15. Alex Jagielski and Eric Hedberg, Guilford Journal of Chemistry, Volume 2, Page 38 (2008).

6


Introduction to the first Issue This first issue of the Guilford Journal of Chemistry includes groundbreaking discoveries in the field of Mentos Eruptions. In its simplest form, the Mentos eruption involves dropping Mentos candy into a soda (usually diet coke), resulting in a foamy eruption, which can often be several meters in height. The first widely viewed Mentos eruption occurred on September 14, 1999 on the David Letterman show,1 though earlier eruptions using other candies (with less spectacular results) had been used primarily by teachers dating back to the 1980’s.2 In terms of scientiic research this field is still in its infancy, sinc e this area of research has almost no peer-reviewed published research results,3 although numerous videos documenting riveting eruptions are available on the internet,4 and on commercial television.5 Several unverified explanations have been offered to explain the eruption6, usually focusing on the physical shape of the mint (so-called nucleation sites), or on the various ingredients in the mint, particularly gum arabic. It is important to note that none of these hypotheses have been scientifically verified. This journal represents the first attempts to scientifically investigate the mentos eruption. Several previously unrepoted discoveries are documented in this journal. Perhaps the most fascinating discovery was made by Cutler and Smith.7 This featured papers reveals that that the height of a mentos eruption can be dramatically increased by freezing a mentos candy prior to dropping it in the soda. Coupled with the predictable observation that heating a mentos candy will increase the height of an eruption, this creates a bizarre result: the the height of a mentos eruption is relatively high when the candy is cold, low when the candy is at room temperature, and then high again when the candy is warm or hot. This discovery could in principle create world-record eruption heights (the current record is 29.2 feet). Another serendiptous discovery was made by Marsh and Moalli.8 While attempting to create a timedelayed Mentos eruption, they chanced upon a method for sustaining an eruption for over 40 seconds. More importantly, their graph suggests that this method could be applied to create eruptions that occur for several minutes in theory, though there were some occasional reproducibility issues that will have to be addressed. Several of these papers are design-based, in which an eruption of a certain type is desired and executed. Methods for creating several spectacular effects are published in this issue. Those interested in creating a unique misting effect should read the work of Necklas and Wall.9 Those looking for both an extremely high as well as a sustained eruption should turn to the work of Davis and Dillon.10 Space does not permit the higlighting of all articles. However, all of these investigations created spectacular eruptions and we hope you enjoy reading about them Dr. H. Brielmann Editor in Chief 7


The Guilford Journal of Chemistry

References: 1. For an informative historical account of the Mentos Eruption, Speve Spanglers website is recommended: (http://www.stevespanglerscience.com/experiment/00000109. Note that the original Letterman Show Mentos Eruption may be viewed on the internet at http://www.chem.uic.edu/marek/letterman0/video/mentos.htm. 2. For accounts of Mentos-like eruptions dating back to the 1980’s, see: Marek http://www.rimmkaufman.com/rkgblog/2007/12/21/steve-spangler/

3. For example, the search term Mentos gives no results currently from popular scientific search engines currently (2008), including PubMed or Google Scholar. Online material is available from the Royal Society of Chemistry (http://www.rsc.org/education/teachers/learnnet/pdf/learnnet/classicdemos/mentosexplosion.pdf), but no experiments were performed in either case to test their ideas. For interesting reading on the explosion of popular online science sources, see http://www.rsc.org/chemistryworld/Issues/2007/December/SurfingWeb20.asp . 4. In addition to YouTube, other websites have arrived that are dedicated to the mentos eruption. Of particular mention is geysertube (http://www.geysertube.com/blog/ UPDATE 2009: dead site), where one can view the Mentos Eruption in ultra-slow motion. 5. For example, on the popular television series Mythbusters (http://dsc.discovery.com/fansites/mythbusters/mythbusters.html). 6. Most literature on the Mentos Eruption cites the website of Fred Senese (http://antoine.frostburg.edu/chem/senese/101/consumer/faq/mentos.shtml), however there are no experiments performed or cited in support of these hypotheses.

7. Rachel Cutler and Emma Smith, Guilford Journal of Chemistry, Volume 1, Pages 6-12 (2007). 8. Steffi Marsh and Taylor Smith, Guilford Journal of Chemistry, Volume 1, Pages 13-16 (2007). 9. Gabriella Necklas and Kiersten Wall, Guilford Journal of Chemistry, Volume 1, Pages 33-35 (2007). 10. Aaron Davis and Travis Dillon, Guilford Journal of Chemistry, Volume 1, Pages 17-18 (2007).

8


The First Four-Way Remote-Control Release Mechanism for Diet Coke and Mentos Eruptions by Ryan Johnson and Will Graziano

Ever since the discovery of the Diet Coke and Mentos phenomenon, numerous experiments have been done for the betterment of science, for "cool factor," or simply for fun. However, we have for a long time been barred from reaching our true potential in the extremity of these experiments for fear of being covered in sticky, fizzy Diet Coke. Many have wondered, "How can we release the Mentos into the Coke without getting soaked? And how can we do multiple releases simultaneously without the need for multiple people to do it manually?" My colleague, Will, and I wondered the very same thing; we wanted to perform a spectacular four-way simultaneous eruption from a safe distance using a remote control device - and after much brainstorming and several different plans, we found a way to do just that. The Experiment Using a table which was approximately .75 meters by 1 meter as our surface, we fixed the engine of a remote control car on its side to the middle, and built a special four-way hook device to hold (and release) fishing lines which would be connected to the Mentos. Four posts of approximately 30 centimeters were fixed to the corners of the table, one in each corner, to which one bottle of Diet Coke each was also secured. With four lengths of fishing line, three Mentos each, and one paper clip each, we devised a line which would hold the Mentos up inside the bottle until the device was activated. When activated, the remote control car engine at the center and the hook device attached to it would spin, unhooking all four lines at the same time and thereby releasing the Mentos into the bottles. Summary of Findings The device, crude though it was, worked just about perfectly - however, we found that the remote control car we used for the experiment was faulty and did not run immediately, so in future experiments a more reliable engine should be used. The result was a spectacular quadruple geyser of Diet Coke spraying into the air, and much applause from our classmates. Conclusions 9


With the success of the device, it is our firm belief that we have revolutionized the Diet Coke and Mentos phenomenon - with added improvements from our successors, it will now be possible to pull off much messier and more impressive displays using the Diet Coke and Mentos combination. Such suggested experiments could be a simultaneous eruption of more than four bottles, or perhaps a wheel device that uses the force of the erupting Coke to spin. The possibilities have suddenly expanded tenfold with this amazing discovery. Experimental Procedure Materials: Supplies to build a table approximately 3 square feet, or such a table pre-built, with a 12-inch post secured to each corner. 4x 2-liter bottles of diet Coke 1x box of Mentos (approx. 24 Mentos) - 12 are needed for the experiment 1x spool of fishing line - any pull strength 1x remote control car -shell removed 1x roll of duct tape - use more as needed 1x board that will fit underneath the remote control car and raise it slightly off the table. 8x paper clips - use more as needed 2x drill bits - one 1/8" and one 2mm wide 4x additional bottle caps for 2-liter Coke bottles - for drilling the holes Safety goggles Procedure: Remote Control Device: 1. Secure the engine to the table such that the wheel is facing up and is as close to the dead center of the table as possible, and that the smaller board is keeping the bottom wheel off the table. Secure tightly with duct tape. 2. Unbend the largest bend of each of four paper clips so that it forms an L-shaped hook with the rest of the paper clip untouched. 3. Secure the paper clips together using duct tape so that it makes a pinwheel-shaped device. 4. Tape this hook device onto the wheel so that the tip of the hooks are all facing in the opposite direction that the wheel is turning. Mentos Strings: 1. Drill one hole in each of the 12 Mentos you will use, using the 2mm drill bit 2. Cut four pieces of fishing line (string), each long enough to cover the distance between the bottle cap and the hook plus about five inches. 3. tie a paper clip onto one end end of each piece of string, conserving as much length as possible. 4. String three Mentos onto each line - the paper clip tied onto the end should prevent the Mentos from slipping off. 5. Tie a small knot on the other end of each string - should be slightly wider than the hooks. 6. Cut extra slack off. 7. Drill one hole in the center of each of the four extra bottle caps using the 1/8" drill bit. 8. String one bottle cap onto each of the lines so that when screwed onto the bottle the Mentos will be inside the bottle. Assembling the whole contraption: 1. Tape one Coke bottle to each post, facing towards the center of the table. 2. Unscrew the bottle cap and screw on the bottle caps with the lines through them. (Note: Recommended this part of the assembly be done after transporting the whole device to the appropriate site for the eruption to reduce the risk of accidental release of the Mentos)

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3. Loop the knots on the other end of the lines onto each of the hooks - there should be no slack between the hook and the bottle, and the mentos should be hanging as high inside the bottle as possible. The lines should be without slack, but not tight. The eruption: Be sure that the whole device is relocated to an appropriate spot for the eruption - it will be very messy, so a flat surface outdoors would be ideal. Hit "forward" on the remote (having already made sure everything is turned on) and the wheel will spin, unhooking the lines and dropping the Mentos into the Coke bottles simultaneously. Suggestions for later repeats - Improve the reliability of the device: Use a higher quality remote control car engine; use safer hooks which will not release until the wheel spins; use more reliable materials to secure the engine and bottles to the table rather than duct tape and nails. - Improve versatility of the device: With a little ingenuity, this concept can be reconfigured for many different types of experiments. Also, contrive a means of making the engine waterproof for reusability. - Devise ever more fantastic and impressive displays of the powers of Diet Coke and Mentos.

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Diet Pepsi –Not Diet Coke – Produces Highest Results in Mentos Eruption When Compared to Other Diet Carbonated Drinks By Angelise Musterer & Lindsay Ruotolo Summary: For our experiment, we took four different types of soda to see the effects of mentos on some carbonated drinks. The drinks we used were Diet Coke (as the control), Diet Pepsi, Fresca, and Sprite Zero. By doing this, we were able to see if this was just a reaction that would occur with Diet Coke and mentos or mentos and the other carbonated drinks too. In the end, Diet Pepsi reached the highest measurement of 94 cm, Sprite Zero came next with a close second of 79 cm, Diet Coke came in third with a height of 43 cm, and Fresca came in last with 15.24 cm. Introduction: When the mentos eruption was tested by the Mythbusters, they concluded that the reason the reaction took place was due to the potassium benzoate, aspartame, caffeine, and CO2 gas in the Diet Coke and the gum Arabic and gelatin in the mentos (http://en.wikipedia.org/wiki/Mentos_eruption the results concluded by the Mythbusters’ experiment). We tested this theory by using different types of soda, and we noticed that in our trials, the Diet Coke did not have one of the biggest eruptions. The world record has been set for the highest eruption using Diet Coke, but we believe that if someone tried other kinds of soda, there might be a new world record. Experimental: 1. Get 2 Litters bottles of 4 different types of soda (Diet Coke, Diet Pepsi, Fresca, Sprite Zero) 2. Get a couple packs of mint mentos 3. Place a measuring tape against a wall, preferably outside!! 4. Set a bottle on a flat ground in front of the tape 5. Get a small plastic tube about the same diameter as the opening of the bottle and insert 3 mentos; place a piece of paper under tube so that mentos don’t fall out 6. Unscrew the cap and put on safety goggles 7. On a count of three pour in the mentos or slide the paper out and step back 8. Watch for the height of the eruption and record how high it goes (its helpful if at the peak of the eruption you take a picture to more accurately know/see the height) 9. Repeat steps 4-8 twice (once for each trial) with each type of soda 10. record all data in a table

Conclusion: In our experiment, we found that the soda that actually worked the best was the Diet Pepsi. This may have something to do with the ingredients in the soda or just may have been experimental error. Since we did only one test for each type of soda due to lack of supplies, we can’t be certain that our results were accurate. In another experiment, in which people used different types of soda and Diet 12


Coke as a control, they did two trials. It was found that there was a drastic difference between the first and second trial (The Guilford Journal of Chemistry, results by Ethan Shore and Zack Brown). Maybe if we did two trails, we would have also seen an increase or even a decrease as they did; finding that our first trial was flawed. Another experimental error could have been that for our first trial using the Diet Coke and Sprite Zero, we used a piece of string to drop in the mentos and in the last two sodas, we dropped them in by hand. This was shown through the fist two sodas, which were the ones that went the shortest height. Other than these errors and the unusual mistakes in measurement and uncontrollable variables, such as the wind or the amount of carbonation that was left in the bottle before we could do the eruption, our experiment went very well. We believe our results are still accurate because the difference between the two sodas’ data (diet Coke and Diet Sprite), it would be hard to justify it as just an experimental error. According to out results, if you were trying a mentos eruption to see how high it could go, it would be best to use Diet Pepsi instead of Diet Coke. References: 1. For background on the mentos eruption, Wikipedia website was very useful and also provided other links that were helpful as well: (http://www.wikipedia.com/). 2. The very popular t.v. show Mythbusters added to our research and ideas: (http://www.dsc.discovery.com/fantacies/mythbusters/mythbusters.html). 3. Dr. H. Brielmann. The Guilford Journal of Chemistry, Volume 1, pages 4-5 (2008). 4. Ethan Shore and Zack Brown. The Guilford Journal of Chemistry. Volume 1, pages 15-16 (2008).

Diet Pepsi Highest Results in Mentos Eruption When Compared to Other Carbonated Drinks

40

35

30

25

Height(inches) 20 37 31

15

10 17 5 6 0 Fresca

Diet Coke

Sprite Zero

Diet Pepsi

Type of Soda

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different flavors resulted in different eruptions. We found that the flavor which had the biggest reaction was cinnamon, with an average height of 10 cm; followed by mint and fruit which had the same reaction, with an eruption height of 8.5; sugar free was second to last with a height of 4.5 and then sour had the smallest eruption with a height of 3.5. We also noted that the sugar free mentos had more foam flow out of the bottle whereas the fruit reacted quickly but left a large amount of foam inside of the soda bottle. The sour mentos was much different as its eruption lasted a long time, with foam and larger bubbles. This leaves cinnamon, which was the quickest reaction and foamiest. 1. Guilford Journal of Chemistry, Vol. One, Page 5. (2008) www.rimmkaufman/rkgblog/2007/12/21/steve-spangler) 2. Guilford Journal of Chemistry, Vol. One, Page 17-18. (2008) 3. Guilford Journal of Chemistry, Vol. One, Page 6-12. (2008) 4. “Fruity vs. Minty� Guilford Journal of Chemistry, Vol. One, Page 2. (2008)

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Cinnamon Mentos Erupt 20% Higher than Mint Mentos By Allison Federici and Jess LaChance

The Mentos and Diet Coke is a very well known experiment that can be dated way back to the 1980’s.1 This experiment deals with dropping any number of mentos into a carbonated soda (usually Diet Coke). When the chemical reaction occurs, a huge eruption of foam shoots out of the top of the bottle. Starting this experiment we knew that mint mentos were the classic or most well known flavor to make the biggest explosion. When people tested different variables they always used either Mint mentos or Diet Coke as their control. 2,3 Previously, some one had tested fruit and minty mentos, but details are not available.4 Since it wasn’t in their title, we assumed that they had not tested more than just fruit and mint mentos. As far as we knew, we would be the first to test five different flavors and their effect on eruption height in Diet Coke. For our experiment we tested the eruption height of Diet Coke depending on the different flavors of mentos. We experimented with regular mint, sugar-free mint, sour, fruit and cinnamon in 8 oz. bottles of Diet Coke. We found the sour and the sugar-free mentos had little to no eruption and the cinnamon mentos erupted only a few centimeters higher than the regular mint mentos. The fruit mentos erupted just as high as the regular mint ones. We were trying to find out if the mint mentos were the best to use, to get the highest eruption. 1. Gather materials, such as 10 8 oz. bottles of diet coke; sugar free, cinnamon, fruit, mint, and sour mentos; plastic tube; toothpick; meter stick and safety goggles 2. Place one bottle of diet coke into sink 3. Fill the plastic tube with 4 sugar free mentos 4. Secure the mentos with toothpick 5. Put on safety goggles 6. Place the tube into top of bottle 15


7. Have meter stick ready next to bottle to record height 8. Pull toothpick out of tube, releasing mentos into soda; quickly pull tube away 9. Record height 10. Repeat steps 2-8 using cinnamon, fruit, mint and sour mentos 11. Repeat steps 2-8 using all 5 mentos flavors for second trials

The Effects of Different Flavored Mentos 12

10

Height (cm)

8

1 2 avg.

6

4

2

0 Mint

Sugar Free

Fruit

Sour

Cinna.

Flavors

The results of our mentos lab were very conclusive. It was shown that, indeed, the different flavors resulted in different eruptions. We found that the flavor which had the biggest reaction was cinnamon, with an average height of 10 cm; followed by mint and fruit which had the same reaction, with an eruption height of 8.5; sugar free was second to last with a height of 4.5 and then sour had the smallest eruption with a height of 3.5. We also noted that the sugar free mentos had more foam flow out of the bottle whereas the fruit reacted quickly but left a large amount of foam inside of the soda bottle. The sour mentos was much different as its eruption lasted a long time, with foam and larger bubbles. This leaves cinnamon, which was the quickest reaction and foamiest. 5. Guilford Journal of Chemistry, Vol. One, Page 5. (2008) www.rimmkaufman/rkgblog/2007/12/21/steve-spangler) 6. Guilford Journal of Chemistry, Vol. One, Page 17-18. (2008) 7. Guilford Journal of Chemistry, Vol. One, Page 6-12. (2008) 8. “Fruity vs. Minty� Guilford Journal of Chemistry, Vol. One, Page 2. (2008) 16


Six Meter Coke and Mentos Eruption Achieved By Heating The Bottle By Mary Melillo and Artem Guryanov

Summary This experiment tested whether the temperature of a bottle of the Diet Coke would affect the height of a Mentos eruption. The first bottle was unheated and acted as our control for the experiment, while the second and third bottles were heated up to different temperatures. Our results made it clear that the higher the temperature rose inside the bottle, the height of the eruption rose in height as well. Introduction Mentos eruptions have been well-known since September 14, 1999, where one was performed on the Dave Letterman show, 1 but tests on effects of temperatures on the bottles before adding the Mentos are not very common. One experiment on the topic claimed that the reaction rate appears to double every ten degree in Celsius that you heat the Diet Coke, and that for every ten degrees the bottle is cooled, the reaction power is cut in half.2 The results of a recent experiment support the idea that warmer temperatures will result in greater eruption height.3 Our experiment tests that theory by heating up the soda to various temperatures and shooting it off, measuring the height of the fizz. Procedure 1. Gather materials: 3 2-liter bottles of soda, 15 mint Mentos (more preferred because some might break apart), string (skinnier is better), a drill, a sink that can produce hot water, thermometer (we used Celsius, but a Kelvin thermometer would eliminate the need for conversions later on), a fourth bottle cap, clamps/pliers, and some sort of measuring device (in meters) 2. Take the drill, pliers/clamps, Mentos, and the fourth bottle cap.

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3. Take the pliers and secure the Mentos to them one by one and drill a hole through them, the pliers are there for your hand’s safety in case you slip and accidentally try and drill your own hand. 4. Drill a hole through the fourth bottle cap as well. 5. Tie a piece of string around the first Mentos and then slide four more on the same string (the length of the string can vary, for best results try a 2-5 inch string length). 6. Take the Mentos on the string, the bottle of soda, the measuring device, the bottle cap, and the thermometer outside. 7. Open the bottle, making sure none of the fizz spills out and slide in the thermometer and record the temperature. That is your control. (In order to best match our results, the control should be about 294.15 K, or 21°C) 8. Slide out the thermometer and slip the string through the hole in the bottle, making sure the five Mentos are on the inside of the cap and screw it on the bottle. 9. Make a countdown and release the string, causing the Mentos to fall into the soda and back away. 10. Watch the explosion and record the height in meters. 11. Repeat steps 3-10 for a second bottle, except this time fill a tub with hot water and rest the bottle in the tub until it reaches 298.15 K (25°C). 12. Repeat steps 3-11, this time for a second bottle and this time heating up the soda to 301.65 K (28.5°C) Note: Be careful when opening the bottles, especially the warm ones, as they will be pressurized when you open them. If you recorded your temperature in Celsius, you may want to convert it to Kelvin (as we did), which is the SI unit of temperature.

Results 18


The control (unheated) bottle of diet coke, which was 294 K resulted in an approximately 4-meter-high explosion. The second bottle, heated to 298 K, resulted in a notably higher explosion, reaching 5.5 meters. Finally, the warmest bottle – at 301 K – created an explosion about 6 meters high. It should be noted that we were not able to run multiple trials and so our data may not prove consisted over multiple tests.

Conclusions Our results clearly support the theory that using warmer Diet Coke will result in a higher Mentos eruption. Each time we raised the temperature of the soda, the result was a taller eruption, with our warmest bottle’s eruption reaching six meters! This can certainly be taken as proof that raising the temperature of Diet Coke affects the eruption size. However, a follow-up experiment where multiple trials are used would be a good idea to test the consistency of this fact. Other follow-up experiments may include heating the soda up to even warmer temperatures, or testing both heating and cooling the soda to compare the effects. References 1. A video of this eruption can be found at: http://www.chem.uic.edu/marek/letterman0/video/mentos.htm 2. Information found from Justin Husted, Guilford Journal of Chemistry, Volume one, Pages 19-20 (2008), where the information is cited from “Username: ‘Labmonkey’ Yahooanswers.com January 10th, 2008.” 3. Justin Husted,

Guilford Journal of Chemistry, Volume one, Pages 19-20

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Names: Mike Amento, Scott Leone Period: 2 Time Delayed Diet Coke and Mentos Eruption By Mike Amento and Scott Leone Introduction: We report here the first time delayed Mentos eruption. This practical device allows the scientist performing this experiment to get clear out of the way of the eruption, offering practical and safety advantage . Experiment: This technique is based on lighting a fuse to run up to the top of the Coke bottle. It was brilliant. The fuse was a long piece of string tightly holding the mentos at the top of the bottle. When we lit the fuse, it took about 10 seconds to burn through the string and break it apart. As the fuse broke, its tight grip on the mentos gave way and they were released into the Coke, thus causing the delayed reaction of the experiment. We were delighted to discover as well that the time delay had no effect on the size of the fountain we were able to form. Each fountain was consistently 6-8 feet tall, and displaced the same amount of Coke. Conclusion: In this experiment we used a flame as a remote device for a mentos eruption. The idea was very successful, and we were able to create a delayed mentos eruption. Our idea was that we use a piece of string as a fuse. We tied the string to the top of the coke bottle and the other end was taped down to the table. We had the mentos hanging off the end of the string, which meant that when the string dropped the mentos would fall into the coke. Then it was as simple as just lighting a candle and placing it close enough to the string so that it would burn it. We came out with times of 15 seconds, 8 seconds, and 10 seconds. This gives us an average time of 11 seconds. It may seem short but it is actually a very good amount of time to get far enough away from the eruption so that you won’t get soda on you. This experiment was a success. Really the only things that we could have changed were the kind of string used, for more variability. References: 1. We got this great idea from Paul Mulligan and Jared Searles’ experiment. They also tried to create a remote for a mentos eruption. “Creation of a remote controlled Mentos Eruption” 2. www.Stevespangler.com

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Title: Volume Analysis of a Mentos Eruption 3. A one paragraph summary of your experiment and results. By Kaitlyn Earles and Megan Graham

Summary: A quantitative volume-based (rather than height-based) measurement technique was developed to assay Mentos eruptions. To accomplish this we measured each explosion by soda displacement and how much was left in the coke bottle and we found the percentage of how much exploded. We were excited to do this experiment because no one has ever tested soda displacement. This technique can be used to measure the intensity of a Mentos eruption independent of eruption height or nozzle size. Introduction Although there have been many experiments that measure how high a mentos explosion is, there is none that is measured by soda displacement. Our observations show how big the explosion actually is by measuring the soda displacement. We tested different volumes and the volumes effect on the explosion. The bigger soda displacement the bigger the explosion, which volume do you think will have the biggest?

Experimental 1. Put on safety goggles 2. Drill one hole in 3 mentos 3. String the mentos and tie a knot at the end of the string 4. Unscrew Coke bottle and very quickly drop mentos inside 5. Measure the volume that’s left inside the coke bottle 6. Find the percentage that is still inside and that has left the bottle. 7. Record all data in a table. 8. Clean up all materials

(use additional space if necessary)

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Results

Volume

Trial 1

Trial 2

Trial 3

Average

12 fl oz 20 fl oz 67.6 fl oz

157 ml 243 ml 800 ml

180ml 267ml 900ml

164 ml 242ml 850ml

167 ml 250ml 850ml

% in bottle 47.3% 42.4% 42.5%

% out of bottle 52.7% 57.6% 57.5%

Most bottles ended up with half the amount it started with. Each explosion needed half the amount of the bottle.

Conclusions In wrapping up the experiment we concluded that the volume does not have an effect on the mentos explosion because as our results showed each bottle had around 50% of soda displacement which means each explosion was about half the size the volume. We were a little disappointed that the volume didn’t have a big impact on the explosion but we are excited to know that no matter how big the volume the explosion will be the same with the same amount of mentos.

(use additional space if necessary)

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Names: Holly Aery and Adam Sierzputowski

Period: 2

Eruptions Caused by Mentos Increase in Height with 3. A one paragraph summary of your experiment and results. Smaller Nozzle Sizes By Holly Aery and Adam Sierzputowski

Summary: We wanted to see how different nozzle sizes of diet coke bottles affect the size of Mentos eruptions. We drilled different sized holes in the caps of bottles creating nozzle sizes ranging from .5 cm up to 4 cm. After dropping in 4 mentos, we were able to see just what kind of eruption the nozzle sizes could create, which was a rather large one of 153 cm, considering we used 20 oz soda bottles.

Introduction: People have previously tried putting mentos in soda just to see it erupt, however it is also very fascinating to learn about why this reaction occurs. According to several untested web sources,1 in the soda, the water is tightly linked around the carbon dioxide which creates a strong surface tension that resists the bubbles from forming and expanding. Then, when the mentos are dropped in the soda, the surface tension is broken from the gelatin and gum arabic in the mentos. These ingredients disrupt the way the water was linked to the carbon dioxide, making it easier for the carbon dioxide to expand, and create a large eruption. There have also been previous attempts by scientists at Guilford High School concerning the same nozzle-size experiments, and similar results were found. Aaron Davis and Travis Dillon found out that the smaller nozzlesizes create higher explosions, which is the same conclusion we had.2 We had also hypothesized that the smallest nozzle would create the highest explosion because it creates more pressure. After all, an explosion is a violent bursting as a result of internal pressure. 3 Therefore, the more pressure there is, the higher the explosion will be able to go.

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Experimental Procedure: The goal of this experiment was to alter eruption height by changing the nozzle sizes of the 20 oz diet coke bottles. At first, we only used 3 mentos but it did not create a large enough explosion so we increased the amount to 4 mentos and tied them on a string to drop them properly. However, we made sure not to include that test trial in our final results. Our positive control was the un-tampered regular sized bottle cap (3.2 cm). It created an explosion that we could compare our other results to because that is the cap size used in regular diet coke and mentos explosions. We did manage to find out, though, that the smallest nozzle size created the largest explosion just as we expected. 1. Gather Materials. - 3 20oz. bottles of diet coke with cap sizes of 3.2 cm - 1 20 oz bottle of vitamin water (empty) with a cap size of 4 cm - 12 mint flavored mentos - String (which you will tie the mentos to) - Drill (to put holes in the mentos/bottle caps - Meter stick 2. Drill a .5 cm hole into each of the mentos. 3. Fill the vitamin water bottle (with a cap size of 4 cm) with diet coke. 4. Drill a .5 cm hole into the cap of one diet coke bottles. 5. Drill a 1 cm hole into the cap of another diet coke bottle 6. String 4 mentos onto a piece of string and tie a knot at the bottom to ensure them not to fall off. 7. Go outside (so as to not make a mess) while taking the diet coke bottle with a 3.2 cm opening (the control) and quickly drop the string of mentos into the bottle. 8. Get about 3 feet away from the explosion and observe and record the height of the explosion. 9. Repeat steps 5-8 using the diet coke with the .5cm hole in the cap. Drop the mentos by holding the mentos string above the liquid through the hole and then dropping the string to create the explosion. 10. Repeat step 9 using the diet coke with the 1 cm hole. 11. Repeat steps 5-8 using the vitamin water bottle (with 4 cm cap) filled with coke 12. Now that all the experiments have been completed, clean up and recycle all soda bottles.

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Results The results we found during the experiment were that the smaller the hole, the higher the soda sprayed. The highest spray came from the bottle with the smallest hole. The hole was .5 cm. around and the soda sprayed 153 cm. high. The largest hole got the least height. It was 4 cm. around and barley got 1 cm. high. Our control went the third highest with an open cap 3.2 cm. around. The control went about 30 cm. high. A 1 cm. hole went 60 cm. high.

160 140 120

Control Open Top .5 cm

100 80 60

1 cm

40 4 cm

20 0 open .5 cm 1 cm top

4 cm

25


Conclusions Due to the data we received we can infer that the smaller the opening the higher the soda will spray and the larger the opening the lower the soda will spray. We found that a hole that was .5 cm. around sprayed about 153 cm. high. We also found that the larger the hole was the least height it got. A hole of 4 cm. (the largest hole) barely got 1 cm. high. From our data we can conclude that the smaller the spray hole the higher the soda will spray. But several issues could have interfered with these results. Number one, we had to pour soda into one of the bottles. This could have made the soda go flat. Two, the bottles could have been shaken causing the soda to become flat. Three, the mentos could have fallen off of the string before the experiment was ready to begin causing an early spray. Some of these miscalculations could have messed up the data we received. To make this experiment more valid we could have done more trials. In a follow-up experiment you should add more trials. Also you have smaller hole sizes to see if the results are valid enough to conclude.

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Title: Comparing Mentos Eruptions of Diet Coke as opposed to JOLT energy supplement By Dylan and Trevor Summary: We decided to compare the Mentos eruption using diet coke with that of JOLT energy supplement. Unfortunately, The reaction using JOLT energy supplement failed to produce a reaction. However, we discovered that the key ingredients in Diet Soda that causes the violent reaction with mentos are Potassium Benzoate and Aspartame. Introduction There is no information prior to our experimentation that could possibly confirm or deny the possible allegations that “liquid energy supplements” do or do not cause a “reaction” with.mentos. The reason that We decided to do our test using liquid energy supplements was by reasoning that synthetic ingredients in the soda cause the reaction. This was found to bot be the case and JOLT energy supplement failed to produce a reaction. However, it led to us to take a closer look at our ingredients, and to discover that Potassium Benzoate and Aspartame are the causes of the reaction with mentos. Experimental 1. Gather Materials (JOLT Energy supplement, copious amounts of Mentos.) 2. Set up controlled environment 3. Don Goggles (no other protective gear required) 4. Create mentos dropping apparatus: mold paper tube to slightly larger diameter to that of the mentos roll, use tape (any kind) to keep in place. Run a toothpick through the extreme on one end, across the diameter. Drop mentos in other side of tube, until full. 5. Suspend full mentos dropping apparatus above can of JOLT, then open can of JOLT and release mentos (remove toothpick from the bottom end of apparatus) 6. STEP BACK. 7. Record data, clean up materials. Results 1 inch eruption Conclusions Our conclusion is that Energy drinks are not the best reactive substance, nowhere near diet coke’s potency. To achieve maximum effect, use as much diet coke as possible, with as many mentos as possible, as unfortunately energy drinks simply cannot produce the desired reaction. There may have been some room for error in the preparation state, perhaps they were shaken up at one point or another, unbeknownst to us, causing them to loose carbonation. If we could do it again, we would definitely use diet coke instead of energy drinks, to achieve maximum explosion. References 1. www.youtube.com/watch?v=IZDFn4VFe9s&feature=related

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HOW THE AMOUNT OF MENTOS AFFECTS THE HEIGHT OF THE ERUPTION Matt Feldman and Alex Monte Introduction: Over the years several scientists have used diet coke and mentos to make a large reaction with only a liter of coke. Many experiments have been conducted to see what factors really do go into making the eruption actually go. Many people have also attempted to break the world record of 29.2 feet in many different forms. Others tried experimenting with different cap sizes, amount of mentos, pressure added to the reaction, and even temperature. We wanted to experiment using a large amount of mentos to get a very high reaction to see if it really had an affect on the height. It requires a large amount of mint mentos, and a lot of confidence in what you are doing. Based on a slip-up by Mr. Monte, future testers are advised to remember to get out of the way after the mentos have been put into the liter of diet coke! Summary: While coming up with this experiment, we had one goal to accomplish when making this test; to break the 29.2 foot record set by previous scientists. We made a careful plan to try and produce the best results and even considered several factors to get the highest reaction. This task was easier said than done, and ended up requiring a lot more mentos to get the record. In the end, we used 5, 10, and 40 mentos as our test, and they each produced a different height. Materials: Regular Mint Mentos (Approximately 9 packages of 14) 3 Liters of Diet Coke Several sheets of 9” X 8” Sheets of Paper Science beakers (Able to accommodate large amounts of mentos) Safety Goggles Tape Measure A Bin to Catch the Eruption if you are Experimenting Inside Safety Rules *Always wear your safety goggles *Be careful with the glass beakers *Do not mess around while conducting the experiment * No horseplay Procedure: 1 Gather materials required to conduct the experiment 2. Take a piece of 9” X 8” piece of paper and roll it into a funnel. Make sure the mentos can get through the smaller end of the funnel, and can accommodate the large amounts of mentos that are going to slide down the funnel. 3. Test the funnel numerous times by putting about fifteen mentos in and out of the funnel so you know the funnel works. 4. Put on Your Safety Goggles

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5. Make sure you are in a safe environment and are in an area where you can measure the height easily. You might want to have someone record a video so you get the exact height. Then take the liter of diet coke, put it in a secure position so it doesn’t fall down and quickly take off the cap. 6. Then quickly place the funnel over the liter of diet coke so the small hole is going into the opening of the bottle. Then pour the beaker of 5 mentos into the wide end of the funnel. 7. Remove the funnel to get your reaction and back up as much as you can so you don’t get sprayed. 8. Repeat steps 4-6 only this time use 10 and 40 mentos for your trials. Don’t forget to write your results in your data table. 9. Make sure to pour the mentos in very quickly or else the reaction will occur too fast and you won’t have an accurate eruption height.

Height of Mentos

Height (Meters)

3.5 3 2.5 2 1.5 1 0.5 0 5

10

40

Number of Mentos This graph indicates that the more Mentos entered into the diet coke, the higher the eruption. When only 5 Mentos were entered the eruption was only 1.02 meters, when 10 were placed in 1.09 meters was the height, and when 40 was put in there was a drastic change and the eruption was 3.5 meters. CONCLUSION After we finished our three trials in the experiment, we determined that the amount of mentos does affect the height of the eruption. The more mentos we put into the bottle, the higher eruption we got. Although we realized that our goal of breaking the record of 29.2 feet was out of reach, we still had fun and realized that trying to get 40 mentos into one liter of coke, and get accurate results is easier said than done. While conducting this experiment, we came up with several flaws that affected the outcome of the experiment. First, while putting the mentos into the liter of coke, we found that it was hard to get every single mentoe into the liter before the reaction actually occurred. A practice test that we conducted, which ended up producing no results at all, showed us that we had to come up with a really good way to get the mentos in quickly and affectively. In the end of that practice test, our method did 30


not work because the funnel slid away, causing no mentos to go in. Therefore we had to result to using a funnel where the small end almost went into the liter. When doing the 40 mentoe trial we poured the beaker of mentos into the funnel which allowed the mentos to slide into the liter. However, the reaction occurred too quickly resulting in the infamous splash on me. This produced flawed results because that could mean that the soda was only reacting to the mentos that made it into the bottle, not all forty. On the other hand, the reaction could have gone higher if I didn’t get in the way. Another thing that we could have changed while conducting the experiment was adding in more trials. We only conducted 1 five, ten, and forty mentoe test, mainly because that was all the supplies that we had. However, if a flaw occurred, like so in the forty mentoe test, we might not get the results we were looking for compared to an average height with 3 trials for each amount of mentos. We also didn’t have a reliable measuring device to get a fully accurate height. We had a tape measure at the wall, and had a video recorder in case we missed the height. Especially for the 40 mentoe test, we had to estimate the height because we were too busy worrying about the slash of soda that we just got on our bodies. As an end result, we did discover that the amount of mentos really does have an affect on the height of the stream. Although we didn’t get completely accurate results, the height of the eruption did climb, the more mentos we put into the liter of coke. From the 5 mentoe test to the 10, the height climbed 0.07 meters and from the 10 mentoe test to the forty, 2.41 meters. That was all we needed to prove our hypothesis. (The more mentos will create a bigger eruption) We had a fun time, and found that setting a record is harder than it looks.

REFERENCES: “Mentos.” Wikipedia, The Free Encyclopedia. 2008. September 9, 2008. http://en.wikipedia.org/wiki/Mentos (world record) Rachel Cutler and Emma Smith. Guilford Journal of Chemistry. Volume 1. Pages 6-12. (2008) (structure of the lab report, expectations guide) Mike Moalli and Steffi Marsh. Guilford Journal of Chemistry. Volume 1. Pages 13-16. (2008) (graph/results guide) Carly Clark and Jenn Agamie. Guilford Journal of Chemistry. Volume 1. Pages 17-18. (2008) (procedure guide)

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A New Accelerant for the BatMobile By Tim Brooks and Ashley Chello

Summary: The experiment tested was to see whether or not Diet Coke and Mentos had a strong enough force to move a toy car. The reaction of Mentos and Diet Coke has always been a mystery, but the wonder if the combination makes a force that is powerful enough to move things, has been solved.

Introduction: This experiment tested something both different and interesting. It was a test to see if a car can accelerate with the help of Mentos and Diet Coke. It was proven true. During this experiment, the hypothesis was, ‘If more Mentos are added to the Diet Coke, then the toy car with go farther.’ There have been experiments with making Mentos Rockets ( 1) and the Mentos reaction height higher but there has not been an experiment along the lines of using it as an accelerant. This is a unique and new way of making toy cars work and move. In this experiment, the group conducted a lab that tested the possibility that using Mentos and Diet Coke will move a toy car. It was successful in making the car move and the group found that the Mentos and Diet Coke lengthened the distance that the car traveled. The control of the experiment was using no Mentos at all. The car along with the Diet Coke taped on top, was tested on the ramp and was found that it traveled a shorter distance then the other trials. The first trial added four Mentos to the Diet Coke. The second trial added six Mentos to the Diet Coke. Both of these trials had an increased distance from the control. Although the experiment was successful, the hypothesis was wrong. Interestingly enough, the trial with only four Mentos traveled a longer distance then the one with six Mentos. Errors might have contributed to the different distances but both were able to show that with the force from the Diet Coke and Mentos, the car was able to move.

Experimental: 1. Begin by gathering duct tape, a toy car (long enough to fit a 2 liter bottle of Diet Coke on it), 3 two liter bottles of Diet Coke, two strips of Green Apple Mentos, a 2x4 piece of wood, a chair, a 25 foot measuring tape, 2 tooth picks, a 2 inch nail, a hammer, a clear, outside area, and safety goggles. 2. Start by making holes in the center of ten Green Apple Mentos with the nail and hammer. 3. Pour out Diet Coke until the soda is at the logo of the Diet Coke. 4. Tape one of the three 2 liter bottles to the toy car. Have the bottle lying on the car, the opening of the bottle pointing to the back and the bottom of the bottle pointing towards the front. Tape it in the center of the car, as straight as possible 32


5. When there are holes in all ten of the Mentos, stick 4 Mentos on one tooth pick and 6 on another. 6. On a flat, clear surface outside tape the 2x4 to the edge of the chair seat. It will make a ramp. 7. Align the measuring tape as straight as possible next to the pathway that the car will be traveling down. 8. Put on safety goggles 9. Test the control to see how far it goes without any Mentos. 10. Put the bat mobile with the Diet Coke at the top of the ramp and let it go. 11. Record the distance the car traveled on your data sheet 12. Test the trials that have Mentos along the same lines. Be sure that when the Mentos are dropped that you have safely released the car as it starts to fizz up.

Results: We tested the effect of a mentos powered car in three different trials. In the first trial we held our controlled experiment where we let the car roll down the ramp by itself without the mentos jetpack. This resulted in the car only traveling 2.15 meters. In our second trial, we duck taped the two leader diet coke to the car so the caped end was facing backwards. Then we added four mentos to it as we released it down the ramp. With the addition of the four mentos, the car traveled a total of 8.33 meters right to the end of the tape measure. Lastly, in our third trial we used the same amount of diet coke in a two leader bottle, but we added seven mentos to it instead of four. This resulted in the car traveling only 4.4 meters. Both the 1st and 2nd trials preformed smoothly without any serious error in the car making it the length of the track. But in the 3rd trial we noticed that the front bumper of the car made contact with the sidewalk as it dismounted the ramp. This caused the car to loose much of its speed that was gained by the exploding soda.

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How the Number of Mentos Effects the Distance Traveled

Distance Traveled (Meters)

9 8 7 6

Zero Mentos

5

Four Mentos

4

Six Mentos

3 2 1 0 1 Number of Mentos

Conclusion: In conclusion, our hypothesis was correct. We predicted that the more mentos that were added to the car, the further the car would travel. We tested our hypothesis in three different trials, a control, and two other trials with the coke, but different amounts of mentos. In the 1st trial, we tested our control, which involved letting the car roll down the ramp with no other force besides gravity. This resulted in the car traveling 2 meters. In our 2nd trial, we attached a two letter diet coke bottle to the 34


car so that the capped end was facing towards the end of the car. We then added four mentos to the bottle and released the car so that the eruption could start as the car was rolling down the ramp and onto the pavement. This resulted in the car going a further distance of 8.25 meters. In our 3rd and final trial, we added another coke bottle, but kept it in the same position. Instead of adding four mentos, we added seven. This resulted in the car only going 4.18 meters. We discovered after examining the car after the trial, that as it disembarked from the ramp, the front bumper made contact with the pavement. This caused the car to loose much of its velocity and therefore the car traveled a shorter distance. This was one of the many errors that may have taken place in this experiment. Other errors that may have occurred were, human20error, and mechanical trouble with the materials. Human error was the easiest kind of error to make in an experiment that requires so much human work and measuring. It is possible that the two trials that the soda was used in may have been slightly different in a few ways. One soda may have been more carbonated than the other or the angle at which they were mounted to the car was slightly different. There were many small errors that were possible. Other than human error, mechanical problems with our material may have caused some influence on the total distance to take place. It is possible that while performing the trials with the soda, that some soda may have spilled into the car, thus resulting in a larger total weight for the 3rd trial to push. Lastly, there was also the problem with the terrain that the car was rolling on. It was a sidewalk that had many cracks and crevices. This may have influenced the total distance of the car because it didn’t follow the same specific track in each trial. To summarize, our hypothesis was correct in which the car with the soda explosion on it traveled a further distance than a car without any means of chemical acceleration. But because of error our idea of how much the mentos make a difference can not be compared accurately.

References 1. http://www.metacafe.com/watch/748953/mentos_diet_coke_rocket_missile/

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The Effect of Diet Drinks on the Height of a Mentos Eruption By Lauren Cutuli Summary: This study tested the effect of different types of diet drinks on the height of a mentos eruption. I tested a twelve ounce bottle and five mentos for each trial, and conducted two trials per drink. Diet Tonic Water produced the greatest eruption with a height of .31 meters and .27 meters. Diet Coke had an explosion of .30 meters and .25 meters. Diet Dr. Pepper had an explosion of .21 and .23. Sprite Zero created the smallest eruption with the results, .19 meters and .21 meters. Introduction: The experiment I conducted is one that is different from the norm, especially while using a tonic water drink. In many drinks, there is an invisible carbon dioxide gas that is released after a bottle is opened. Also, inside the drink, water does not let the carbon dioxide bubbles expand. When the mentos are dropped inside the drink, the gum arabic and the gelatin separate the carbon dioxide gas allowing bubbles to expand and form new ones as well.1 The weight of the mentos plays a role in this experiment as well. As the rather heavy candy falls down towards the bottom of the bottle, carbon dioxide is released. The amount of pressure given off by the carbon dioxide pushes the drink out of the bottle.2 Experimental: The design of my experiment was to test the reaction of mentos and different types of diet drinks. I tested four different types of drinks; Diet Coke, Diet Dr. Pepper, Sprite Zero and Diet Tonic Water. I conducted two trials per drink by using mentos to drop into each one. A meter stick was held by the soda so that when the drink erupted, a measurement could be recorded. I used twelve ounce bottles for the drink and five mentos per trial. Procedure: 1. Gather two twelve ounce bottles of Diet Coke, Diet Dr. Pepper, Sprite Zero and Diet Tonic Water 2. Gather three packages of mint flavored mentos and a plastic tube with a hole at the bottom 3. Get a meter stick for measurement records and have someone help hold the meter stick for you 4. Get and put on safety goggles 5. Place the bottle in the sink 6. Put five mentos in the tube with a toothpick at the bottom, keeping the mentos secured 7. Open the top of the bottle 8. Place the tube in the top of the bottle 9. Remove the toothpick 10. Record the height of the eruption 11. Repeat all steps for the same type of drink then again for additional drinks to complete two trials each

Results:

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The Effect of Diet Drinks on the Height of a Eruption(m)

Height of

Mentos Eruption 0.4 0.3 0.2 0.1 0 Diet Coke

Diet Dr. Pepper

Sprite Zero

Trial One Trial Two

Diet Tonic Water

Type of Diet Drink

Trial One Diet Coke

Trial Two 0.3

0.25

Diet Dr. Pepper

0.21

0.23

Sprite Zero

0.19

0.21

Diet Tonic Water

0.31

0.27

Conclusions: My conclusions show that the Diet Tonic Water and Diet Coke were reactive drinks when mentos were put in the bottle. The Diet Tonic Water, after both trials, recorded the highest eruption with the heights of, .31 meters and .27 meters. Diet Coke was the second most reactive drink, from my results, with the combination of mentos. The heights for this drink were .30 meters and .25 meters. Diet Dr. Pepper was the third most eruptive drink and the measured heights for this diet drink were .21 meters and .23 meters. Lastly, the Sprite Zero had the smallest reaction towards the mixture with mentos and the heights were .19 meters and .21 meters. References: 1. For information about Mentos eruptions: (http://www.newscientist.com/channel/fundamentals/dn14114-scienceof-mentosdiet-coke-explosions-explained.html) 2. For a historic record about Mentos eruptions: (http://www.stevespanglerscience.com/experiment/00000109)

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Communications (summaries only) Discovery of the Worlds Longest Mentos Eruption: One Hour and Forty Minutes. By Sam Taylor and Will Schaffer Melted mentos and diet coke will create a sustained eruption lasting consistently over one hour in duration.

Drilling a 5 mm Hole in a Mentos Candy Results in a 20% Increase in Eruption Height. By Nick Hill and Kyle Gaboury Modified mentos were tested in 1 liter Mentos candies eruptions.Eruption heights were 95 cm for standard mint mentos candies, 20 cm for mint mentos candy powder, 65 cm for mint mentos with the coatings removed, and 120 cm for mentos candies with a 5mm hole drilled in the center.

Karo Soda Cold SyrupIncreases Quenchesthe theHeight MentosofEruption a Mentos Eruption By Andrea Cawley, By Morgan KelseyEhrler, Robinsand andPam Laura Salmeron Turcio A simulated The effect of volcano soda temperature eruption using ondiet the coke, height mentos, of a mentos corn syrup, eruption andwas redinvestigated. food coloringInproduced a side byno Mentos side study, eruption cold diet whatsoever. coke produced It is suggested, an eruption but ofhas 275not cm,been compared tested, tothat 150 Karo cm for Syrup roomistemperature the ingredient diet coke which quenches this reaction. . Mentos Sliced in Half will Double the Height of a Mentos Eruption

By Emily’s Ring and Kipness In a height-comparison study of the Mentos eruption, it was found that average eruption heights were 58 cm for a cleanly sliced half-mentos candy, 35 cm for crushed mentos, and 25 cm for unmodified mentos candy.

Serendipitous creation of a Mentos Rocket Several researchers have confirmed that cold or warm mentos erupt By higher Alex Jagielski than room andtemperature Eric Hedberg. mentos, including Andrew Austin and Rachel Spadacenta, Ray Trombetta and Brad Tucker, Kevin Kelly andtaping By Matt Husted, an inverted, Kiersten drilled Kenefick graduated and cylinder Kristen Fradiani to a 2 L bottle of diet coke, a visually stunning sixway horizontal eruption was created. During one of these trials the taping came loose, resulting in a three meter upward flight of a mentos rocket. If developed safely, this could form the basis for numerous mentos ballistics investigations.

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1


Andrew Bonner Period 8 September 29, 2009 Diet Coke and Mentos Eruption

In the Mentos-Diet Coke reaction there are several different variables that can be modified in order to change the results of the reaction as with any other experiment. The temperature of the soda and the temperature of the Mentos and the can be a major deciding factor to the height of this reaction. The source of this reaction is believed to be caused by the small pores in the Mentos outer covering acting as nucleation sites for the tiny carbon dioxide bubbles to form on the surface of the Mentos. These bubbles eventually break away from the Mentos surface and float to the surface of the soda and there form an explosive reaction of foam due to the large volume of foam in the relative small amount of space it has to expand in inside the bottle. Surprisingly, this is actually a physical reaction since the sodas physical form is the only thing that ever changes1. The question is, does the temperature of either the candy or the soda or both affect the height of the reaction. When the temperature of the Mentos is raised or lowered the height of the reaction is clearly changed in relation. As tested by Cutler and Smith the coldest Mentos proved to create the highest reaction at a rough estimate of 350 cm when ten Mentos were cooled to a temperature of 263 K. Surprisingly the next highest reaction was the one caused by the heated Mentos. When ten Mentos were heated to 313 K the reaction reached a height of 200 cm. The lowest reaction was caused by Mentos left at room temperature (303 K) which caused a reaction height of 30 cm 2. These results show that the height of the reaction is directly affected by the temperature of the candies added to the soda. These results also bring the questions of will changing the temperature of the Mentos more drastically make the height of the reaction? If the

2


Mentos that were cooled were only cooled 10 K similarly to the heated Mentos only being heated 10 K, would the difference in the height between the heated and cooled reactions change? Furthermore, Why did the Mentos that had there temperature change react so violently when compared to the reaction from the Mentos left at room temperature? Does it have something to do with the fact that the Mentos temperature was changed not the way they were changed (heating or cooling)? It would be plausible to conclude from this data that the eruption height has a direct relation to the difference in temperature of the Mentos common temperature and changed temperature. It seems as though changing the temperature was the only reason that the reaction was effected, not the way the temperature was changed. In addition, the temperature of the soda also had an effect on the height and length of the Diet Coke-Mentos reaction3. As tested and proven by Husted, the height and length of the reaction is clearly dependent on the temperature of the soda. When Diet Coke was cooled to a temperature of 262 K, heated to a temperature of 308 K, and left a temperature of 298 K the reaction was clearly was affected. The soda that was cooled produced a reaction height of 20 cm. The soda left a room temperature surpassed that by five times with a reaction height of 100 cm which was outdone by the heated soda which produced a reaction height of 300 cm4. This drastic change in reaction height is probably due to the fact that all of the carbon dioxide in the Diet Coke expanded in the heated soda and contracted in the cooled soda. Since the carbon dioxide had a much greater volume in the heated soda when compared to the cooler sodas, the volume of the foam was much greater causing a higher reaction. Furthermore, the carbon dioxide wasn't the only ingredient in the Diet Coke to expand; as common with most substances, as temperature increases so does the volume of the substance. This would have caused the eruption to further exceed the capacity of the soda bottle.

3


As you can see, there is a direct relationship between the temperature of the ingredients and the height of the reaction. Oddly, the effects of the temperature change aren’t similar between that of the Mentos and that of the soda. As the Mentos were heated or cooled the height of the reaction would increase while the height of the reaction was only increased when the soda was heated. This starts the idea that the volume increase and decrease of the Mentos has very little to do with the height of the reaction, since height increased even when the Mentos were cooled and contracted. The pores in the surface of the Mentos, which act nucleation sites in this case, are more or less affected by the changes from there natural temperature. For whatever reasons, the nucleation sites are more able to produce bubbles and create more violent reactions. On the other hand, the increase in reaction height may not have anything to do with the nucleation sites at all; this difference may be the product of some other substance in the surface of a Mentos that was affected by the change in heat making it more apt to have violent eruptions. Overall, the height of the Diet Coke-Mentos eruption is dependent upon the temperature of the reactants.

1. American Journal of Physics, Volume 76 number 6 Tonya Coffey 2008 2. Guilford Journal of Chemistry, Volume 1, Cutler and Smith 3. www.stevespanglerscience.com, Mentos and soda temperature. 4. Guilford Journal of Chemistry, Volume 1, Husted 5. Guilford Journal of Chemistry, Volume 2, Melillo and Guryinov

4


Sahil V. Makhijani Tuesday, September 29, 2009 Period 8 Brielmann Hon. Chem.

Mentos Review Paper The Effect of Flavor on Eruption Height Ever since it was first discovered, the diet coke-and-mentos eruption has been recreated several times on TV shows and viral videos, most famously by Fritz Grobe and Stephen Voltz, who call themselves the Eepybirdsi. The Eepybirds have made guest appearances on several TV shows, set records for their absurd eruption videos, and continue to tour to this day. However, they claim to use conventional Diet Coke and mint Mentos for their eruptions. There is a numerous variety of Mento flavors, other than mint, including mixed fruit, cinnamon, grapefruit, plum, raisin, yoghurt, currant, and even fresh colaii. The Eepybirds, along with The Mythbustersiii, claim that the combination of mint Mentos with Diet Coke creates the greatest eruption. Jamie Hyneman of the Mybusters duo states that the fruity flavors have a smooth, waxy coating compared the mint kind. This smoother coating results in bad nucleation sites for a smaller eruption. However, other studies indicate that the more fruity flavors will cause a bigger reaction than the standard mint flavor. One example comes from a paper written by Tonya Shea Coffeyiv, definitively states that fruit mentos resulted in a larger displacement of soda mass in the bottle, as well as a longer spray distance than regular mint mentos (and diet coke). Her experiments claim that fruit mentos displaced 30g more diet soda than mint, while the spray from the fruit mento reaction flew 1.5ft farther than the spray from the mint mentos. Another investigation, conducted by fellow high school students Allison Federici and Jess LaChancev, compared five different mento flavors: mint, fruit, sugar-free, sour, and 5


cinnamon. Two trials were conducted with each flavor (and diet coke) for the height of the spray. Their results conclude that the cinnamon mentos resulted in a spray 1.5cm higher when reacted with the diet coke compared to the regular mint. In comparison to Coffey’s investigation, the mint mento and fruit mento eruption heights were practically identical in both of their trials. Nevertheless, this data also confirms that mint mentos are not the best kind for diet coke eruptions. As further investigations on the ideal mento flavor for a better eruption continue to contradict each other, we begin to wonder about the truth behind the sweet phenomenon. Since this topic is considered irrelevant to the field of research and investigation, we may never really find out enough about the chemical process and the key ingredients that are responsible. However, we have uncovered some plausible explanations for the reaction: the concept of nucleation on the surface of the mentos explains for the sudden rush of CO2, diet soda works better than regular soda and carbonated water, and mint mentos may not be the best type of mentos for a bigger eruption. Hopefully, we will one day discover the ideal combination of soda and candy for the biggest and best eruption.

i

Eepybird’s website: http://www.eepybird.com/ Wikipedia, “Mentos- Flavors”: http://en.wikipedia.org/wiki/Mentos#Flavors iii Overview on the Mythbusters episode on diet coke + mentos (quote by Hyneman): http://www.zap2it.com/tv/news/zap-mythbustersmentos,0,4325641.story iv American Journal of Physics (article by Coffey): http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=AJPIAS000076000006000551000001&idtyp e=cvips&gifs=yes v Guilford Journal of Chemistry, Vol. 2 pgs. 15-16: http://chemistryadventure.com/Documents/guilford%20journal%20of%20chemistry%20volume%202.pdf ii

6


Rebecca Mahoney September 29, 2009 Period 8

The Effect of Temperature on the Height of Mentos and Diet Coke Eruptions As some previous studies have shown, the temperature of diet coke in a mentos eruption does have an effect on the height of it. The hotter the beverage is, the higher the eruption will be. In one experiment, cold (262 K), room temperature (298 K), and warm diet coke (308 K), was used to differentiate their affects on the height of a mentos eruption.1 Besides the temperature, everything else was the same about each trial. Each bottle had eight mentos put into it when conducting the experiment. After the testing took place, the expected results were found.2 The bottle with warmest diet coke had the highest eruption, the room temperature diet coke had the second highest eruption, and the coldest diet coke had the lowest eruption. 3 In another experiment, the same types of results were found. The temperatures used for the experiment were 320 K, 311 K, and 284 K.4 1

This experiment was tested by Justin Husted and was in the Guilford Journal of Chemistry under the title of “Warm Soda has a Dramatic Effect on the Height of a Mentos Eruption.� The soda got to the certain temperatures by putting the bottles in water of the desired temperature. The middle temperature of soda was kept in the classroom for two days, instead of being put in water. 2

The expected results were that warmer soda has a greater reaction

3

The highest reaction was 300 centimeters, the second highest was 100 centimeters, and the lowest reaction was about 20 centimeters high.

7


In another experiment, the same types of results were found. The temperatures used for the experiment were 320 K, 311 K, and 284 K.4 Also, the results were not showing the differences in heights of the eruptions, but the amount of mass (g) lost. 5 It did not say how many mentos were put in each diet coke bottle either, but used 30 grams of mentos in each. It did say they were mint mentos, though, which is the same type used in the other experiment by Justin Husted. The hotter the beverage, though, the more explosive reaction was concluded. It said that the temperatures affect on the mentos eruptions was due to Le Chatelier’s principle: P=Kc.6 In the experiment, the stress applied increases the temperature of the diet coke. This moves the system away from equilibrium condition for the molar concentration of gas. This means when the mentos are dropped into the liquid, the system moves toward equilibrium which is the explosive reaction.7 From the work of Tonya Shea Coffey and Justin Husted, it can be seen that hotter beverages create larger mentos and diet coke eruptions. Even though there is a very limited amount of studies, research, and experiments on the general topic as a whole, it seems as though these results contain valid answers. This concludes that, the warmer the diet coke is, the larger the explosion of the mentos and diet coke will be. 4

This information was found in “Diet Coke and Mentos: What is really behind this physical reaction?� by Tonya Shea Coffey. These temperatures were originally in degrees Celsius, but were converted into Kelvin. 5 The highest temperature had an amount loss of 1450 grams, the middle temperature had a mass loss of 1350 grams, and the lowest temperature had a mass loss of 1280 grams. 6 P is the partial pressure of the gas above the liquid, K is a parameter, and c is the molar concentration of the gas. 7 The system moves toward equilibrium by liberating the excess carbon dioxide from the solution. 8


Caleb Fridell Sept. 29, 2009 Period 8

Mentos Review Article: Effect of Nucleation Sites on Mentos

The many pits covering the surface of Mentos candy popularly known as nucleation sites are credited by many as the source for the fantastic eruptions when the candy is dropped into soda. Mentos candy has a very rough surface, with thousands of microscopic nucleation sites. The theory is that these nucleation sites provide areas for the Carbon Dioxide bubbles to form, and rush to the surface of the soda. When the Mythbusters tested this theory1, they used one normal Mint Mento, and a Fruit Mento, which was layered with a wax sealer that Jamie claimed inhibited the nucleation process. Their first test used the Mint Mento, which was covered with nucleation sites, as a control. As predicted, the soda erupted when the Mento was dropped in. However, when the smooth surfaced Fruit Mento was dropped in, there was absolutely no eruption. The Mythbusters concluded that the cause of the eruption was the rough surface, which contained several nucleation sites. For videos of the experiments and further explanation, see the Mythbusters episode1. In her report, “Diet Coke and Mentos: What is really behind this physical reaction?�2 Professor Coffey identified the roughness of the Mento as a major factor for the eruption. Coffey proved this by taking SEM images of the Mentos and other tested substances to measure the roughness of the surface. The Mentos, which had a rms roughness of 442, had a much higher root-mean-square roughness than other test subjects such as Rock salt, which had a rms 9


roughness of only 174. The eruption results showed a positive correlation with the roughness. The Mentos tested had a more explosive eruption, and the soda lost much more mass with the Mentos than rock salt. However, the Wint-o-Green Lifesavers showed a much higher rms roughness with an astounding 2630 but failed to create eruptions that were more explosive or cause a larger loss in soda. From this information, Coffey concluded that although the roughness of the surface created more nucleation sites and thus created better eruptions, they were not the sole factor, as Wint-o-Greens were rougher but had worse eruptions. Lee Marek, who was the first major performer of the Mentos and Diet Coke experiment appeared on the 1999 David Letterman Late Show said that the reaction was due to nucleation sites3. Marek said that dropping anything into the carbonated Diet Coke would produce the bubbles but since Mentos had so much surface area and places where the Carbon Dioxide could nucleate, its reaction was biggest. Marek said that the reaction was solely because that the Mento broke the surface tension, and provided nucleation sites, and then sunk to the bottom to push the soda out of the bottle3. All three of the scientific studies that were reviewed agreed that the nucleation sites were a major factor in the eruption because the bubbles were formed in the pits, and the Mento sunk to the bottom to push the soda out of the bottle. However, Marek gave this as the only reason, and did not conduct sufficient studies to prove his theory. Having seen that the Mentos caused an eruption, and that they had several nucleation sites, he listed this as the only reason without providing a substance with as many nucleation sites to compare as Coffey did (Wint-o-Green Lifesavers). His theory was shown to be correct by the Mythbusters and Coffey, but his experiments alone were not sufficient proof. The Mythbusters tested the nucleation sites well, proving that they were one of the causes of the eruption, and also cited the other reasons. 10


Coffey’s report went into the greatest detail of the three, giving ample explanation with all of the necessary proof to give support. In conclusion, the Mentos played a major factor in the eruption, but were not the sole cause.

1

Mythbusters “Episode 57: Mentos and Diet Coke”, Discovery Channel

2

“Diet Coke and Mentos: What is really behind the physical reaction?” Tonya Shea Coffey,

American Journal of Physics, Volume 76, Number 6, June 2008 3

Lee Marek on David Letterman Late Show 1999, Lee Marek Website

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Amanda Simon September 29, 2009 Honors Chemistry Period 8

The Effect of Soda Temperature on the Soda Mentos Eruption Review Article Introduction Various experiments have been conducted concerning the soda Mentos eruption to discover what specific factors influence the reaction to produce the largest eruption. Some of these factors include the type of Mentos, importance of nucleation sites, Mentos temperature, soda eruptions without Mentos, and varying nozzle effects. An additional factor that is significant in the reaction is the temperature of the soda. Not many experimenters have dared to test this factor but it plays an important role, actually producing a much larger eruption when the soda is warmer. A few studies have been conducted to support this claim. Experiments One study conducted by Justin Husted in 2007 specifically proved that for every ten degrees Celsius that Diet Coke is heated, the reaction rate appears to double and similarly, for every ten degrees Celsius that Diet Coke is cooled or frozen, the reaction rate decreases by half.1 The temperature of the soda also affects the height and power of the reaction in that the warmer the temperature, the greater the reaction force and height.2 The experiment consisted of placing three bottles of diet coke into different water temperatures which were cold (262 K), room temperature (298 K), and warm (approximately 308 K). A controlled number of 8 Mentos were placed in each bottle to discover the effect of the soda temperature of the reaction. In Husted’s experiment, the eruption in the warm soda produced an explosion 300 cm high while the cold

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soda explosion was only 20 cm high.3 Clearly, the results were clear and accurate, proving warmer beverages produce greater eruptions while the cold soda produced the smallest reaction. Another study conducted by Professor Tonya Shea Coffey of Appalachian State University involved the investigation of the effect of soda temperature on the eruption height of the soda Mentos reaction. Using contact angles, an AFM, and an SEM as tools in the numerous experiments, Coffey was able to arrive at several conclusions as to what conditions yield the largest, most effective eruptions. Related to the effect of soda temperature on the explosion, Coffey and her team used Henry’s law which applies to gases dissolved in liquids to show that a beverage with a higher temperature will produce a more explosive reaction. 4 When the parameter K increases with the temperature increase of the soda, the molecular concentration of the gas drops to create the same value of partial pressure as before.5 The drop in concentration means that the gas becomes less soluble in liquids with the temperature continuing to increase.6 Le Chatelier’s principle applies because it states ‘If, to a system at equilibrium, a stress be applied, then system will react so as to relieve the stress.’7 The temperature increase causes the system (soda) to move away from equilibrium but when the mento is dropped into it, the system begins to move back toward equilibrium by freeing the excess carbon dioxide from the solution by exploding.8 Coffey’s work obviously supports the fact that the hotter the beverage, the more explosive a reaction will be. Conclusion There are numerous factors which affect the height and force of the widely spread Mentos exploding in soda reaction. A majority of the causes have been discovered through various experiments performed unofficially by everyday people, students in classrooms, or by Professor Coffey. The different experiments have proved continually that the temperature of the 13


soda severely affects the height and force of the eruption. The hotter the beverage is, the larger the explosion. This is supported by Husted’s experiment where the hot beverage caused an eruption 15 times higher than the eruption created by the cold beverage. Additionally, Coffey’s experiment displayed that a soda of increased temperature produces a higher eruption by using Henry’s law and Le Chatelier’s principle to explain the reason why this is true. All of the relevant research consistently show that the hotter a soda is, the larger an explosion it creates.

________________________________________________________________________ 1

Justin Husted, Guilford Journal of Chemistry, Volume 1, Page 19 (2007). Justin Husted, Guilford Journal of Chemistry, Volume 1, Page 19 (2007). 3 Justin Husted, Guilford Journal of Chemistry, Volume 1, Page 19 (2007). 4 Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction? Page 556 (Accepted in 2008) 5 Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction? Page 556 (Accepted in 2008) 6 Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction? Page 556 (Accepted in 2008) 7 Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction? Page 556 (Accepted in 2008) 8 Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction? Page 556 (Accepted in 2008) 2

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Micaela DeMasi-Sumner Period 8 September 26 2009

Diet Coke and Mentos Eruptions Diet Coke and Mentos explode when they come in contact. The typical experiment used to prove this is done by dropping Mentos in a bottle of Diet Coke and running away. The eruption can vary from a few inches to several feet in height depending on what alterations where made to the typical experiment. In order to observe the full effect of the eruption, Mentos should be tied to a string and dropped in the Diet Coke bottle, this allows the experimenters to be sure the Mentos will not miss the bottle when being dropped. There is no limit to the possible types of eruptions Diet Coke and Mentos could make together. Both ingredients have been around for decades, so many of the possible forms of explosions have been tried. Explosions have been tried on television as well as in classrooms and houses, but they can all be shared over the internet in places such as YouTube, and Google Videos. On YouTube videos have been submitted as long ago as 3 years. This is a considerably long time ago because YouTube is still fairly young.1 By searching “diet coke and mentos” on YouTube, thousands of videos will come up as results. The eruptions are mostly not scientifically sound and do not support scientific ideas; they are mostly just done for entertainment. However, the MythBuster’s result and the Letterman Show’s demonstration are also a part of YouTube and can be viewed. “The Diet Coke and Mentos reaction was the subject of a 2006 MythBusters episode and first shown in 1999 on the David Letterman show.”2 This experiment was 15


historically done to pass time in a fun manner and is still used that way today. By being shared in public, a larger population then in past times became aware of the reaction. Although there is not one sure ingredient or ‘thing’ that is solely responsible for the reaction the MythBusters were able to target one cause. As is shown on the MythBuster’s show, and is available on YouTube, the Diet Coke and Mentos reaction is demonstrated by the professionals on the show. They found out that nucleation was a large contributing factor in the explosion. They explained this by describing the process like the following; pitted increased surface area allows CO2 to bubble and attach to Mentos and then release causing the bottle of Coke to erupt.3 The MythBusters also stated that the fruit Mentos were smooth and ‘waxy’ so they did not cause an impressive eruption, but in eruptions done by Tonya Shea Coffey prove that fruit Mentos actually do erupt on a large scale. Fruit Mentos were dropped into Diet Coke in Coffey’s eruption and the spray was 17.8 ft at it greatest height.2 These experiments were not even the first to be done ever, but they were documented so the general public could easily find out when they occurred. The exact date of the first ever Diet Coke and Mentos eruption is unclear, but, the dates Coca Cola was invented and Mentos were invented are easily looked up. Coca Cola was invented in 1886 by Doctor John Pemberton.4 However, Mentos came many years later. Michael van Melle and Pierre van Melle invented Mentos in 1932.5 So the original reaction could not have taken place before the invention of both ingredients, so the reaction came no earlier than 1932.

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In conclusion, Mentos and Diet Coke eruptions take place when the two ingredients touch. These explosive reactions can be seen on YouTube as well as on re-runs of MythBusters. These experiments have been done for at least a decade but possibly longer. Nucleation is one explanation for the reaction of Diet Coke and Mentos, but there is not much scientific information to back other theories. This is a simplistic experiment that demonstrates possible happenings between two seemingly random substances. Overall, the results will vary, but Diet Coke and Mentos will explode when mixed together because they have a history of doing so.

1. 2. 3. 4. 5.

YouTube. This site contains many results on Diet Coke and Mentos eruptions. Tonya Shea Coffey. Diet Coke and Mentos: What is really behind the reaction? This article was published in the American Journal of Physics. MythBusters- Diet Coke and Mentos: Season 5, Episode 12. The results of this episode are available on YouTube. http://www.solarnavigator.net/sponsorship/coca_cola.htm This site explains who invented Coca Cola, and when it was invented. http://www.mentos.com/?tld=us#/FAQ This is a site dedicated to Mentos information and publicity.

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Ted Jensen Period 8 Nucleation Sites and the Diet Coke-Mentos Reaction The explosive combination of Mentos mints and Coke has been the target of scientists, entertainers, and students alike. When combined, the soda is released as a jet of Coke through the top of the bottle. Studied by Mythbusters and other formal studies such as that of Tonya Coffey, the cause of this reaction has not been formally identified, but one of the identified main causes is the nucleation sites. Nucleation is the process by which bubbles form on surfaces. In a soda factory, carbon dioxide gas is pumped into the soda with a lot of pressure. The result is the carbonation of the soda, or “fizziness,” where the gas stays suspended in the bottle until it is able to escape or form bubbles 1. But why do these bubbles form? An article on the Royal Society of Chemistry gives a good explanation. Because gas is more soluble at higher pressures, a large amount of carbon dioxide is able to be forced into a pressurized bottle of soda 2. When the bottle, is opened, the pressure is reduced and the “liquid is momentarily supersaturated with gas.” The gas begins to escape and does so through bubble formation. When bubbles do form, they form on the sides of the bottle or on another object within the bottle. This stays with the theory that bubbles form on surfaces 2. Michael L. Corradinni, a professor at the University of Wisconsin School of Engineering describes the formation of “vapor from a liquid” when he states, “Vapor may form from a liquid (a) at a vapor-liquid interface away from surfaces, (b) in the bulk of the liquid due to density fluctuations, or (c) at a solid surface with pre-existing vapor or gas pockets. In each situation one can observe the departure from a stable or a metastable state of equilibrium” 3. The idea that vapor

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forms at a “solid surface with… gas pockets” shows exactly what is happening to the mentos. Though

Mentos look smooth and even feel it sometimes, they are not. According to the Mythbusters’ Adam Savage in an episode about the Mentos-Cola explosion, the “surface of the [mentos] is covered with microscopic pits and lots of more surface area than you can actually see” 4. The rough surface of the Mentos provides these “gas pockets” and nucleation sites for carbon dioxide bubbles to form. According to Professor Tonya Coffey, in her article Diet Coke and Mentos, a regular Mint Mentos has a “Root-mean-square roughness” of 442 nanometers, as opposed to a Wint-ogreen Lifesaver at 2,630 nm, and rock salt at 174 5. With this measure, it can be determined that a Wint-o-green lifesaver is the most rough, followed by the Mint Mentos and finally, the rock salt. Because the Mentos candies have a surfactant present that sets them apart from others tested, it is more important to look at the differences between more similar variables: the Lifesaver and rock salt. Coffey states that the Lifesavers have and rms roughness of “more than a factor of 10” larger than that of rock salt. The Lifesavers, when placed in Diet Coke, caused a total mass lost of 1430 g and a spray distance of 7.0 ft. The rock salt, also placed in Diet Coke, caused a total mass of 1170 g lost and spray distance of 6.3 ft. Clearly, the Wint-o-green lifesaver, the candy with the greatest roughness, caused a more massive and powerful explosion of Diet Coke. An increase in the number of nucleation sites will allow more carbon dioxide bubbles to form and escape. Though nucleation sites are not the sole cause of the Diet Coke- Mentos reaction, they are a large contributor to its explosive result. For the absence of nucleation sites on a Mentos candy would not allow the formation of carbon dioxide bubbles, and therefore cause no or a very small eruption. 19


Endnotes 1. Steven Spangler has done numerous experiments and demonstrations with the CokeMentos phenomenon. His article on the explosion can be found here: http://www.stevespanglerscience.com/experiment/00000109

2. The RSC, or Royal Society of Chemistry, is a European organization of scientists that publish articles on their website about specific topics. The Diet Coke-Mentos Explosion article can be found here: http://www.rsc.org/education/teachers/learnnet/pdf/learnnet/classicdemos/mentosexplosion.pdf

3. Michael L. Corradinni is a professor at the University of Wisconsin School of Engineering. He published an article not specifically on the Mentos experiment, but on the topic of bubble nucleation. His articles is published online: http://wins.engr.wisc.edu/teaching/mpfBook/node27.html 4. Mythbusters is a popular Discovery Channel show involving several different aspects of science. One of their shows covered the science behind the Coke-Mentos reactions. A small segment of it can be viewed on the Discovery channel website: http://dsc.discovery.com/videos/mythbusters-diet-coke-and-mentos.html 5. Diet Coke and Mentos: What is really behind this physical reaction? by Tonya Shea Coffey describes an experiment performed at Appalachian State University, coverin many aspects of the reaction. Results, procedures and discussions can be viewed online: http://planck.lal.in2p3.fr/wiki/uploads/Photos/Activit%E9esClandestines/Coffey08_diet_ coke_and_mentos.pdf

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Joe DeLucia 9-29-09

The Effect of Soda Temperature on the Height of Mentos Eruptions Several experiments have been conducted to test the famed Mentos- Diet Coke reaction, but few have tested this reaction to see if soda temperature influences the magnitude of the eruption. In a recent experiment, data proved to show that for every 10 degrees Celsius the Diet Coke was heated, the reaction rate was doubled (as well as every 10 degrees Celsius it was cooled the reaction rate was cut in half).1 It has also been noted that temperature plays a key role in the force and height of the reaction based geyser. 2 Based upon this data, as temperature increases or decreases, the height of the reaction also increases or decreases with it.

1)

2)

3)

Temperature (Kelvin)

Height (Meters) 3

294.15

4

298.15

5.5

301.68

6

Temperature (Kelvin)

Height (Meters) 4

263

.2

298

1

308

3

Temperature (Kelvin)

Mass Lost (grams) 5 21


279

1280

311

1350

320

1420

All three of these result listings come from different experimenters who were all trying to discover the correlation of temperature and height in this infamous reaction. While all three results have different increments for temperature, different temperature to height ratios, and a different variable in one case, they all lean towards the same discovery. Comparing results 1 and 2, they both show that as temperature is increased, height also increased. Results 1 had an approximate 4 Kelvin increase with each level of its independent variable, allowing a chance to see a rhythmic pattern when compared to the height. Though no such pattern did clearly occur, with more levels of the independent variable, this very well may have been discovered. If the experimenter were to come up with a device more reliable then eyeto-ruler vision for the height results, perhaps a pattern might have been able to be detected. As for results 2, equal increments were not used, causing the data to be seemingly one dimensional. The height averages also seem oddly small to what they would normally be, being that Results 1 only used 5 Mentos per bottle and Results 2 used 8 per bottle. This is because the experimenters in Results 1 used a larger quantity of Diet Coke (2 Liters) 6 compared to that of the experimenter in Results 2(1 Liter) 7 showing that the quantity of reactants influences the overall reaction. It should be noticed that there is a .8m increase in 263K to 298K (35K difference) and a 2 meter increase in 298K to 308K (10K difference). This strongly contrasts with the theory stated in the beginning that with every 10 degrees Celsius warmer the soda gets, the reaction will double. Being that only one trial for each temperature was conducted by the experimenter for Results 2, 22


the results cannot strongly stand up against the previous statement, and may be somewhat inaccurate based on this (although this is only a theory). Results 3 measure temperature compared to mass lost instead of temperature to height. Again, this experiment only had one trial for each level of the independent variable and is therefore not fully conclusive. However, the idea of measuring the mass lost instead of height seems more valuable because it is much more exact in measuring the power of the reaction than estimating the height traveled. In general terms, these results support that of the other two graphs in the sense that with increased temperature comes a more active reaction. It can be concluded that with a higher temperature of soda, the reaction will be stronger and therefore, travel higher than that of a soda with a cooler temperature. This could be because the extra thermal energy naturally excites the molecules, and when the reaction takes place, some of this thermal energy is converted to kinetic energy, causing the height of the eruption to tower over a reaction that contains less thermal energy. A clear rhythmic pattern, however, cannot be traced from this data because of the lack of sufficient trials and equal increments that were used. If a sufficient amount of trials along with equal increments were to be experimented upon with temperature and height. The theory that an increase in 10 degrees Celsius will double reaction rate can be proved. 1

Guilford Journal of Chemistry, Vol. 1. “Warm Soda has a Dramatic Effect on the Height of a

Mentos Eruption” by Justin Husted. Originally from “Username: ‘Labmonkey’ yahooanswer.com January 10, 2008.” 2

Guilford Journal of Chemistry, Vol. 1. “Warm Soda has a Dramatic Effect on the Height of a

Mentos Eruption” by Justin Husted. Originally from www.stevespanglerscience.com mentos and soda temperature. 23


3

Guilford Journal of Chemistry, Vol. 2. “Six Meter Coke and Mentos Eruption Achieved By

Heating The Bottle” by Mary Melillo and Artem Guryanov. (Results) 4

Guilford Journal of Chemistry, Vol. 1. “Warm Soda has a Dramatic Effect on the Height of a

Mentos Eruption” by Justin Husted. (The Experiment) 5

“Diet Coke and Mentos: What is really behind this physical reaction?” by Tonya Shea Coffee.

(Results and Discussion) 6

Guilford Journal of Chemistry, Vol. 2. “Six Meter Coke and Mentos Eruption Achieved By

Heating The Bottle” by Mary Melillo and Artem Guryanov. (Procedure) 7

Guilford Journal of Chemistry, Vol. 1. “Warm Soda has a Dramatic Effect on the Height of a

Mentos Eruption” by Justin Husted. (Procedure)

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Amanda Levy Period 8 9/29/09 How Temperature of Diet Coke Affects the Diet Coke and Mentos Reaction Review Although period 8 did not get the opportunities to test variables involving the Diet Coke and Mentos reaction, other resources have provided information about what happens when the temperature of the Diet Coke changes. One resource states that for every ten degrees Celsius the Diet Coke is heated, the reaction rate doubles, and for every ten degrees it is cooled, the reaction power is cut in half.¹ Even though this is stated in the Guilford Journal of Chemistry Volume One and then refereed to again in the Guilford Journal of Chemistry Volume Two, the original source is yahooanswers.com. To go beyond this unreliable claim, experiments done by Coffey, Justin Husted, Mary Melillo, and Artem Guryanov will be examined throughout the paper. Coffey investigated how the Diet Coke’s temperature effected the reaction by refrigerating one bottle for several hours prior to the experiment, and heating the other bottles in a water bath on a hot plate for about ten to twenty minutes.² The problem with this is that the bottle had to be opened before heating, and then closed again so that pressure could be released which prevented an explosion. Because the cold and room temperature bottles were not opened, the early release of some carbon dioxide gas might have caused the warm bottle to be less explosive. Another reason these results may be inaccurate is because she only performed one trial for each temperature. The results were examined only how much mass was lost, not the length or height of the explosion. Coffey’s found the following results: when the temperature of the Diet Coke was 47 degrees Celsius, the amount of mass lost was 1450 g; when the temperature of the Diet Coke was 38 degrees

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Celsius, the amount of mass lost was 1350 g; and when the temperature of the Diet Coke was 6 degrees Celsius, the amount of mass lost was 1280 g.³ It should be noted that results may be not be precise because only one trial was done and only mass lost was recorded instead of mass lost, height, and time. Another approach to testing these materials is to submerge the bottles in different water temperatures to change the temperature of the Diet Coke. This eliminates the variable of letting carbon dioxide gas out before which could affect the end result of the explosion. This is what Justin Husted did in his experiment. ⁴ He reported his results in terms of the height of the reaction. Again, only one trial was done for each temperature which could result in unreliable data. Mary Melillo and Artem Guryanov had almost the same set up for their experiment (they also submerged bottles in water to change the temperature) except they only increased the temperature of two different bottles and did not investigate the effects of cooling the bottles. ⁵ Husted found the following results: the soda that was submerged in cold water and was 263 K lead to an eruption that was 20 centimeters high; the soda that was left in the classroom for 2 days to ensure average room temperature and was 298 K lead to an eruption that was 100 centimeters high; and the soda in the heated water that was 308 K lead to an eruption that was 300 centimeters high.⁶ It should be noted that results may be inaccurate because only one trial was done and only height was recorded as opposed to height, mass loss, and time. Melillo and Guryanov found the following results: the unheated bottle was 294 K and resulted in an explosion 4 meters high; the bottle heated to 298 K resulted in an explosion 5.5 meters high; and the bottle heated to 301 K resulted in an explosion 6 meters high.⁷ It should be noted that these results might not be accurate because height was measured in meters, only one trial was done for each temperature, and only height was recorded as opposed to height, mass loss, and time.

26


Conclusions It is very clear in all of the papers that as the temperature of the Diet Coke increases, the eruption size also increases. In Coffey’s research, there is a clear correlation in the data that shows as temperature is increased, the amount of mass lost increases. Coffey clearly states, “…hotter beverages result in a more explosive reaction.”⁸ This conclusion proves clear in both of the other article as well. In Husted’s research, the data shows a direct correlation that as the Diet Coke temperature is increased, the higher the explosion. Husted states, “By the results of the data, it is easily safe to conclude that the warmer the diet coke temperature, the more height the eruption gained.”⁹ Melillo and Guryanov’s data also prove true to this pattern; with every increase in temperature, there is an increase in the height of the explosion. Their paper states, “Our results clearly support the theory that using warmer Diet Coke will result in a higher Mentos eruption.”¹⁰ Even though all of these experiments had only one trial each, there was no exception to the theory that as the temperature increases, the eruption will also increase in any of the experiments. Because of this, it is safe to make the conclusion that as the temperature of Diet Coke increases, so does the eruption size.

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v

Courtney Streeto September 27, 2009 Period 8

The Effect of Different Types of Carbonated Beverages on Mentos Eruptions

For years the eruptions created by the dropping of Mentos into sodas has been a phenomenon. The classic Mentos reaction has been made with the combination of Diet Coke and the original mint Mentos, because this mixture seems to produce the ideal reaction. In reality, however, other carbonated beverages seem to work just as well as the Diet Coke. It seems that most carbonated drinks will produce a suitable reaction. Most different types of carbonated drinks create a reaction, with the exception of energy supplements, because they lack the key ingredients for an explosion, potassium benzoate and aspartame.v These ingredients are included in diet soda, which is why diet coke is often chosen for the ideal reaction.v When tested, the JOLT energy drink did not respond to any number of Mentos, while diet soda will. Any non-diet drink also creates a lesser reaction. In tests with mint Mentos, the measurement of the height of the Coke explosion ranged from .125m in an experiment done by studentsv to 3.536m in an experiment designed by scientist Coffey2, making it the lowest nondiet measured reaction. Sprite also had a small reaction, .51m, which can also be said for its lack of key ingredients. 3

28


Tests were performed on different types of diet sodas, including Diet Coke and Diet Pepsi. In one of the few published peer-reviewed articles on Mentos eruptions, Coffey concludes that Caffeine Free Diet Coke has the highest explosion when tested with mint Mentos at 4.968m. In student experiments, however, sodas other than diet and none diet Coke were tested. One group of students saw that the smallest reaction of the diet drinks was Fresca, which traveled a height of .152m, followed by Diet Coke at .432m, then Sprite Zero at .787, and Diet Pepsi had the biggest explosion at .940m.v In another student experiment Diet Coke had an eruption of .85m and Sprite Zero had the highest reaction of 1.052m. 5 Yet another experiment with all diet carbonated beverages showed the following results: Sprite Zero had the smallest reaction with a height of .20m, followed by Diet Dr. Pepper at .22m, the second biggest reaction was from Diet Coke with .275m, and the greatest was Diet Tonic water with .29m.6 The results of these tests cannot be taken as proven fact because Mentos explosions are very rarely documented, and there need to be more published tests done to compare results with. For example, it cannot be deduced that all energy supplements have no reaction with Mentos based on the fact that JOLT did not have one. The conductors stated that there is no prior information about energy drink reactions. 7 More tests involving more energy drinks would have to be done in order to see if this type of carbonated drink can provide a reaction. Also, it is clear that each person conducting the experiments, from Coffey to students, received different results. This is because each person most likely had their own way of performing the experiment. Validity is in question, with things like whether or not the cap was on the soda, how many Mentos were used, expiration date, and factors that involved human error such as measurement. 29


However, when the results of every experiment are compared, it is obvious that a diet soda is much more explosive than a non-diet one. It may not be clear which diet soda is the best, but all will produce a reaction outdoing that of a regular soda. This is because each diet soda contains the active ingredients in a Mentos-soda reaction: potassium benzoate and aspartame.8 When searching for the ultimate eruption, one should use diet soda over any other beverage.

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Sarah Jonathan Period 8

The Effect of Soda Temperature on Mentos Eruptions The Coke and Mentos eruption experiment is a popular activity but there is not often very much data collected on this topic. On e aspect of this reaction that has been tested is the effect of soda temperature on the size of the explosion. There have been multiple experiments done on the effect of soda temperature on explosion size that hypothesize that a warmer soda will result in a larger eruption. In one experiment done by Mary Melillo and Artem Guryanov state that “one experiment on the topic claimed that the reaction rate appears to double every ten degree in Celsius that you heat the diet Coke.�v This would be a significant increase in height if it were correct. In one experiment students tested bottles of diet coke with varying temperatures. They tested one bottle at 294 K, another at 298 K, and the last at 301 K. according to their report the first bottle at 294 K resulted in a 4 meter eruption, the second bottle at 298 K resulted in a 5.5 meter eruption, and the last bottle at 301 K resulted in a 6 meter high explosion.v This shows that when they increased the temperature by 7 K the height of the explosion increased by 2 meters. This is not quite the reaction that was predicted by the earlier mentioned experiment in that lab but it is still a large increase in the height of the explosion. In another experiment done by students the same procedure was followed except that Instead of measuring the temperature of the soda, the bottles were placed in water of a certain temperature for a constant amount of time. They had three different temperatures; these were coke submerged in 263 K water, coke left at room temperature or approximately 298 K, and coke

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submerged in 308 K water.v In their results they stated that the height did increase with the temperature and the 263 K bottle had an explosion height of 20 centimeters, the 298 K bottle had an explosion height of 1 meter, and the 308 K bottle had an explosion height of 3 meters.v These results show that when there was a 45 K change in the substance the soda was heated in then there was a corresponding 280 centimeter change in the height of the explosion. In one other Experiment done by professor Coffey the experimental procedure was the same but the data collected was the amount of mass lost in the explosion not the height of the explosion. Coffey tested three temperatures of soda, these were at 320 K, 311 K, and 279 K.v Coffey’s results were similar to the results of the other two experiments. She stated that the higher the temperature of a bottle, the more mass lost in the explosion, which means the larger the explosion. In Coffey’s results the bottle of soda at 279 K lost 1280 grams, the next at 311 K lost 1350 grams, and the last at 320 K lost 1450 grams.v This shows that with a difference of 41 K there was a corresponding difference of 170 grams lost. Each of the above experiments had different results, however all of them demonstrated a clear relationship between the temperature of the bottle and the size of the explosion produced by this experiment. Although all of these tests had only one trial each when viewed together it is possible to conclude that the higher the temperature of the bottle of soda is, the bigger the resulting explosion will be. This is because if you view the three separate experiments as one, each could show one trial and the same conclusions would be made. In order to fully analyze however, more experiments with more trials would be needed.

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Accidental Discovery of a Five Minute Mentos Eruption By Alysia Colandrea & Andrea Gava Summary: Originally, the design of this experiment was made to create a delayed mentos reaction by boiling mentos in water at a temperature of 473 K for 50 seconds. This heat would melt away the outer shell of the candy and any possible nucleation sites that could possibly be the reason for mentos explosions. As a result from the heat, rather than a delay in the explosion, a small reaction took place that stayed for an average of 5.17 minutes. Where a controlled mentos that was not boiled had an average eruption time of 31 seconds. Although the reaction of the boiled mentos didn’t drastically shoot into the air, the fizz continued for a very long period of time. Introduction: The mentos eruption is a well-known experiment where a mentos (one or more) is dropped into a soda—normally Diet Coke or Diet Pepsi—and a chemical reaction would occur where an eruption would over flow the bottle. The first well known Mentos Eruption was in September of 1999 on the David Letterman show, although the study had began around and in the 1980’s by teachers around the world even though they used various candies rather than mentos. Over the years, scientists and students have experimented with the Mentos Eruption attempted to create a sustained eruption that could last several minutes. It has been proved that melted mentos and diet coke will create a sustained eruption lasting consistently over one hour in duration. The reaction between Diet Coke and mentos usually produces a good reaction and is frequently tests, but if you were trying a mentos eruption to see how high it could go, it would be best to use Diet Pepsi instead of Diet Coke. Experimental Section: Our experiment was carried out by boiling 9 mint mentos and placing three in a 20 oz. bottle of Diet Pepsi, three more in another bottle, and the last three in a third bottle. We then watched the eruptions and timed how long they were carried out. We then did the experiment again with 9 mint mentos that were not boiled and timed them as well. Conclusion: In response to our original hypothesis that a heated/boiled mentos would created a longer reaction, we created a test in which consisted 9 mint mentos heated on a hot plate at 473 K and three 20 oz. bottles of Diet Pepsi. We then separated the heated mentos and placed three in one bottle, three in another, and three in the third having a steady constant of the number of mentos in each bottle. After watching the reactions go on for about five minutes, we concluded that the boiled mentos reaction was much longer than a controlled mentos (not boiled) which had an average eruption time of 31 seconds (rather than the 5 minutes and 17 seconds that the boiled mentos had. Mentos consist of many nucleation sites that are places where the carbon dioxide can make bubbles. A nucleation site can be a scratch on a surface, a speck of dust, or any place where you have a high surface area relative to volume. We figured that if the nucleation sites were boiled, they would evaporate or melt off of the mentos along with the outer layer, making the reaction more sustained. With a result of an eruption average time that is almost five minutes longer than the controlled mentos, our hypothesis was proved and we were found correct. Experimental Procedure: Materials: 1. 6 20 oz. Diet Pepsi Bottles at room temperature 2. 18 Mint Mentos 3. Hot Plate 4. Thermometer 5. Timer (Stopwatch) 6. Goggles 7. Access to water 8. Glass Beaker (100 mL in each trial) 9. Tweezers Procedure: 1. Put on your safety equipment, such as your goggles. 2. Line up all six soda bottles at room temperature in a line about one and a half meter apart from each other. 3. Separate the 18 mentos into 6 groups, each containing 3 mentos. 4. Turn the hot plate on

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5. Place the glass beaker on top with the 100 mL of water 6. Place 3 groups of mentos into the beaker with water and wait until the water temperature goes up to 473 K. (or 200 ºC.) 7. Do these separately 8. Measure the temperature with your thermometer in Celsius and convert it to Kelvin, by adding 273 to your temperature. 9. Pull the each group of mentos out separately with your tweezers 10. Place one group of the boiled mentos in one of the Diet Pepsi bottles 11. With your timer record the time that the combination of soda and mentos erupt for. (you will know that there is a reaction, when the soda starts to bubble, and fizz, it does not have to erupt) 12. Write the time of the eruption down 13. Repeat steps 9- 11 with the other two groups of boiled mentos, and the other 2 soda bottles 14. Take the last 3 groups of mentos that should not have been boiled and separately place each group of them in the last 3 20 oz. soda bottles. Once again time the eruptions (this should not fizz, it should actually erupt) and record your information. 15. Once you have all of your information recorded figure out the time average of the boiled and non-boiled mentos, simply by adding all three trial of each and dividing them by 3. 16. Clean up Results: After we did the experiment we got three different eruption times which included a 4.49, 5.12, and 5.8 minute eruptions making an average of a 5.17 minute eruption. Mentos Reactions Trials Eruption Time Trail One Heated 4 minutes, 49 seconds Trial Two Heated 5 minutes, 12 seconds Trial Three Heated 5 minutes, 8 seconds Average Heated 5 minutes, 17 seconds Trial One Control 37 seconds Trial Two Control 24 seconds Trial Three Control 32 seconds Average Control 31 seconds

References: • Discovery of the World’s Longest Mentos Eruption: One Hour and Forty Minutes .Sam Taylor and Will Schaffer. Guilford Journal of Chemistry. Volume 2. Pages 38. (2008) http://chemistryadventure.com/Documents/guilford%20journal%20of%20chemistry%20volume%202.pdf • • •

Marek. (http://www.rimmkaufman.com/rkgblog/2007/12/21/steve-spangler/) Mentos. http://en.wikipedia.org/wiki/Mentos#Mentos_and_soft_drink_reaction Mentos Eruption, Speve Spanglers. (http://www.stevespanglerscience.com/experiment/00000109)

• Mentos Eruptions are increased by heating or Cooling the Mints. Rachel Cutler and Emma Smith. http://chemistryadventure.com/Documents/guilford%20journal%20of%20chemistry%20volume%202.pdf • Stories Tagged Nucleation Sites. http://www.sciencebuzz.org/buzz_tags/nucleation_sites

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Observing the Surface of a Mentos By: Nick Latella and Allison Paradis Summary: In our experiment we observed the surface of a mentos using a high powered microscope and a camera adapter that attached to it to project the images that were under the microscope into a form that can be seen by more than one person at a time. We were trying to see what causes the eruption between the Diet Coke and the mentos by closely looking at the surface to see what imperfections there were. In the end we observed that when the mentos is exposed to the soda the cracks and fissures cause the CO2 to form a bubble which then dissolves the rough outer coating of the mentos. We believe this is due to what is called nucleation sitesv. Introduction: We only found a handful of experiments that had significant information and proof to back it up. One of them being the experiments done by Dr. Tonya Coffey, she and her team had done many experiments to figure out why the eruptions occur. To the naked eye the surface of the mentos candy is smooth but under a microscope the surface looks coarse. The coarse bumps are called nucleation site, each tiny nucleation site become a place where a bubble of CO2 gas can form and rapidly rise out of the soda. Multiply the one nucleation site by the many found on the mentos and you get thousands of bubbles forming continuously until the soda dissolves the outer layer and the mentos becomes smooth.v In Steve Spangler’s experiment he explains what happens when the mentos interacts with the diet coke. He says that as the mentos descends into the soda the CO2 gas fill the fissures in the candy and the bubbles formed carries the liquid up and out of the bottle.v Another experiment was done by the popular television group, Mythbusters, in which they identified the ingredients in the mentos and in the soda. After they had acquired these ingredients they tested each to see which would cause the eruption. They came up with; the CO2 gas and the aspartame in the soda (artificial sweetener), and the gelatin and gum arabic in the mentos, they concluded that these were the main ingredients in the reaction.v All of the previous experiment stated were valid and are proof of nucleation sites.

Experimental Section: In our experiment we observed the surface of a mentos by using a simple microscope. We started off by placing the mentos candy onto the slide. We had an external light source such as lamp, or in our case, a flash light, because the mentos candy was too thick for the microscope light to show through. We started on 40x magnification just to get the mentos in focus. Once we had this done we changed the magnification to 100x, from here we focused the image and attached the electronic camera adapter to the microscope. With this, we projected the images to a larger screen and then took pictures of the image seen. We used a normal digital camera and uploaded the photos to a computer. Using a disposable pipette, we added 2 35


drops to the mentos, waited for the small reaction to occur, then refocused the microscope and took pictures of the result. Materials:

 A pack of Mentos candy  Access to a microscope  Access to an attachable electronic camera adapter  One 1L bottle of diet coke  One 12oz of diet coke  Camera (preferably digital)  Disposable pipette  Lamp or flash light  Balloon  Adult supervision Procedure: 1. Gather materials 2. Open pack of mentos and place one mentos under the microscope and start at a low 40x magnification, get the image into focus. 3. Once the image is in focus move up to 100x magnification and again check to make sure the image is in focus. 4. Attach the electronic camera adapter to the microscope and connect it to a projector or a television screen. 5. Using a digital camera, take 2-4 pictures of the images shown on the screen. 6. Once done, use a pipette and fill it with diet coke. 7. Drop two drops of the diet coke onto the mentos and watch the physical reaction take place. 8. Record observations. 9. Once the reaction is over, dab dry the mentos with a paper towel and put back onto slide. 10. Take off the camera adopter. 11. Refocus the image by hand by using the 40x magnification until what is seen is half of the mentos that was affected by the soda and half that wasn’t. 12. Refocus with the 100x magnification. 13. Reattach the camera adopter. 14. Using the digital camera take 2-4 pictures of the images shown on the screen. 15. Record Observations.

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Conclusion: After conducting our experiment we have concluded that the cause of the eruption is the CO2 filling the cracks and fissures which forms bubbles. These bubbles end up rapidly ascending upward and carrying the soda molecules with it forming the eruption that is so famously known. When the reaction has occurred the soda ends up dissolving the rough surface of the mentos down to a smooth area in which the reaction cannot again because there are no more cracks and fissures for the CO2 gas to form a bubble. As a follow up experiment, someone repeating this experiment can take a 1L bottle of soda and attach a balloon tit e top and then agitate the soda until all of the CO2 gas has escaped from the bottle and it becomes “flat�. The when you drop the mentos into the bottle no reaction occurs, therefore the CO 2 gas is the main factor in the reaction. For further reading please refer to the references cited below.

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GUILFORD JOURNAL OF CHEMISTRY VOLUME 4 2010-2011 MENTOS LAB!

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Warm m en t o s c r e a t e a l a rg e r e r u p t i o n when c omp a r e d t o c o l d e r and r o o m t em p e r a t u r e m en t o s

Summary On average, the mentos frozen at (10째C) reached , on average, 1..58 meters which is less than the warm mentos (70째C) that reached 2.60 meters on average. All of this data when compared to the control group (room temperature) that reached an average of 1.25 meters shows that change in temperature will cause a change in eruption height and that the warm mentos made the highest eruption. Introduction: The mentos experiment has been completed thousands of times, but there has only been one published paper, by Tonya Shea Coffey. There have been many different trials and experiments to figure out what causes the eruption along with what factors may increase and decrease eruption height. There are many theories from the molecular makeup of the soda to the physical make up and texture of the mentos. The experiment made here is to determine if the temperature of the mentos affects the eruption height. This experiment has also been completed many times by researchers Emma Smith and Racheal Cutler(1).

Experimental Procedure 1. Gather materials, 27 regular mentos, 9 cokes, meter sticks, safety goggles, flat launch area, mentos dropper. 2. Freeze 9 mentos to 10 degrees Celsius, and warm 9 mentos to 70 degrees Celsius 3. Take 3 mentos and place them into mentos dropper and place pin 4. Quickly open coke and screw on mentos dropper then place the coke on a flat surface 5. Go to a safe distance away from the coke and countdown from 5 and pull the pin be carfeul to make sure the area is clear of people 6. Record height of eruption in meters 7. Repeat 2 more trials for freezing mentos and record data 8. Then repeat these steps for warm mentos and the control group room temperature mentos and record data Results 2


The data was not very exciting or very separated. Each eruption was between 1.15 or 2.2 meters high. However it was conclusive enough to figure that the warm mentos heated to 70째C created the highest eruptions, peaking at 2.2 mentos.

Mentos Temp.

Cold (10째c)

Warm (70째C)

Control (Room Temp.)

Test 1 height (m)

1.3 m

2.2 m

1.25 m

Test 2 height (m)

1.7 m

2.0 m

1.15 m

Test 3 height (m)

1.7 m

1.75 m

1.5 m

3


Mentos Heights

Key: Column 1: Green = warm Column 2: Purple:= Cold Column 3: = room temmperature

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Conclusion The results found in this experiment were comparable to the ones found by other tests that dealt with temperature change of mentos. The freezing mentos and the warm mentos created larger eruptions than the control group room temperature mentos. Although the data was not exciting in the results for the eruptions it proved that the warmer mentos will make a higher eruption than freezing or room temperature mentos. The warm mentos on average reached 2.63 meters while the freezing reached only 1.5meters on average and the room temperature mentos only reached an average of 1.25meters each time. The data although flawed at time due to human error such as variation in drop time can cause minor variation in data however the data is credible compared with data found by other experiments. The warmer mentos most likely increased the eruption height because molecules were hotter therefore when it came time for the reaction the activation energy required was reached faster and the eruption had more energy and therefore made a higher eruption. This reasoning destroys the validity of the colder mentos because naturally the colder mentos should slow down the reaction time and take away energy making a smaller eruption however the eruption was higher than the control group which had warmer mentos. However, the results of other tests verify the results in this experiment so the reasoning for the colder mentos large eruption must still be found out.

References This is a list of peer reviewed books and journals that you are using to support your research. No websites may be used. The numbers correspond to the superscripts in the paper. In the end it should look something like this: 1. Kaitlyn Earles and Megan Graham, Guilford Journal of Chemistry, Volume 2, Pages 21-22 (2008). 2. Tonya Coffey, American Journal of Physics, Volume 76, number 6, pages 551-337 (2008). 3. Nick Hill and Kyle Gaboury, Guilford Journal of Chemistry, Volume 2, Page 38 (2008). 4. Read page 553 of Coffey's paper (see reference 2) for a detailed analysis of the effect of pH on the height of a mentos eruption. 5. Ryan Johnson and Will Graziano, Guilford Journal of Chemistry, Volume 2, Pages 9-11 (2008). 6. Alex Jagielski and Eric Hedberg, Guilford Journal of Chemistry, Volume 2, Page 38 (2008). For full credit include a minimum of 5 useful references formatted like the ones above.

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Summary An experiment was conducted to determine the effect of the temperature of diet coke on a Mentos eruption. Three different temperatures were used, and each had a total of three trials. The coldest set ‘s (at 283 K) eruption reached an average height of .7 meters. The room temperature set (at 300 K) reached an average height of 1.6. The hottest temperature set (at 308 K) reached an average height of 2.3 meters. To summarize the results, the conductors of the experiment developed a mathematical formula: The temperature increases with the height, so if the temperature is doubled, so is the height. It was found that the higher the temperature, the higher the height of the eruption.

Tx=Hx T=temperature H=height Ex: 2 x T, then 2 x H

X=variable

Mentos Eruption in Diet Coke

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Introduction A Mentos eruption is when one or more Mentos candies react with soda, or another substance, and then the substance erupts. Though there are some hypotheses why the Mentos react with soda, none of them have been confirmed. Despite this, people are still conducting experiments to alter the reaction. One of the less common experiments is differing the temperature of the soda. The hypothesis that the group is leaning towards is, “If there is an increase in temperature in the diet coke, then there will be an increase in the height of the eruption because the molecules are moving at a much faster pace, making the bottle more pressurized and much likelier to have a huge “popping” effect.” There have been many experiments on altering the temperature of the Mentos (it was found that increasing the temperature of the Mentos increased the height, and freezing them greatly increased it) but there are much fewer on the temperature of the actual soda.1 Another person has come to a conclusion similar to our own: that when the temperature of coke is doubled, the height also doubles.2 Clearly the temperature of the coke has a drastic effect on the height of the eruption. Another experiment used a control group at room temperature, and two higher temperatures for the independent variables. The experiment once again supported that heating the bottle greatly increases the height of the eruption. 3 One theory about why temperature effects the height of the eruption is that as temperature increases, gases are less soluble in liquids. In other words, the carbon dioxide is less soluble in the soda as the temperature increases, so it leaves the liquid, and builds pressure in the bottle.4 That is why a warm soda fuzzes or spurts more than a cold one when you first open it. When the bottle is opened, the increased gas pressure is released into the Mentos, which causes an explosive reaction. This relationship is represented by Henry’s Law, P=Kc, or the partial pressure of gas above the liquid equals the parameter (which increases with temperature) times the molar concentration of solute. 5 This research supported the results of our experiment, and let us know that our data are reliable.

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Experimental Procedure 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27.

Gather all materials Label the small diet cokes with numbers 1-9 in permanent marker for distinguishing purposes Bring everything outside to a flat surface near a wall Place numbers 1-3 in cold water Place numbers 7-9 in hot water Lean ruler vertically against wall Put on safety goggles (wear as often as possible, very important piece of equipment) Open package of Mentos (open as needed throughout experiment) Lift up plastic ring and insert red string through tube Untwist red top from tube and insert three Mentos Twist on top Place Bottle 4 near the ruler and wall, as vertically as possible Open Bottle 4 and measure and record temperature in Celsius (Convert to Kelvin later) Quickly twist on Mentos tube (Be careful not to pull out the string by accident) Step away slightly, holding onto string Have your partner hold the bottle Pull string out Record height as accurately as possible in meters Remove tube from bottle and set bottle aside Repeat steps 9-19 for Bottles 5 and 6 Remove Bottles 1-3 from cold water Repeat steps 9-19 for Bottles 1-3, in the order 1, 2, 3 Remove Bottles 7-9 from hot water (Careful not to burn yourself. Ask for assistance if needed) Repeat steps 9-19 for Bottles 7-9, in the order 7, 8, 9 Clean up all materials Remove safety goggles Return all of the materials provided for you to teacher or appropriate area

Materials •Safety Goggles • Meter stick •9 small diet coke bottles (3 extras in case of accidents) •3 packs of Mentos •Tube for geyser w/ string to stop Mentos from falling (should be provided for you) •Thermometer (Celsius) •Data table •Writing utensil •Flat surface for Mentos Guilford Journal of Chemistry

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Results

Height of Eruption (Meters) Temperature (Kelvin)

Trial 1

Trial 2

Trial 3

Average

Cold

283 K

.5

.75

.8

.7

Room Temp.

300 K

1.75

1.55

1.5

1.6

Warm

308 K

2

2.6

2.3

2.3

Height of Eruption (Meters)

Height of Mentos Eruption for Different Diet Coke Temperatures

Height of Mentos Eruption for Different Diet CokeTemperatures 2.5 2 1.5 1 0.5 0 283 K

300 K

308 K

Temperature of Diet Coke (Kelvin)

Mathematical Formula Tx= Hx The height increases with the temperature. If the temperature is doubled, or multiplied by another number, so is the height.

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Conclusion It is possible to safely conclude that the height of the eruption will increase with the temperature and therefore, the hypothesis is supported. When the temperature was 283 K, the height was, on average, approximately .7 meters. When the temperature was increased to 300 K, the height increased to an average of 1.6 meters. When the temperature was further increased to 308 K, the height increased to its highest, an average of 2.3 meters. Each time the temperature is increased, the height does as well. The data do vary, but they follows the trend of increasing in height with temperature. The trials all fall within the same basic range for a given temperature, so it is still rather repeatable. Also, the data are rather reliable because there were multiple trials for each temperature, and the room temperature soda serves as a control group. The mathematical formula is not perfectly precise, because we could not control the temperature well enough (290 K, 300 K, and 310 K, would be better). If we were to extrapolate data, however, we would get a result close to what the actual data would be. For example (using Celsius so the change is not excessive) if the height at 27˚C is 1.6 meters, then the height at 54˚C is around 3.2 meters. The reason why the height depends on the temperature is because the higher the temperature, the less soluble carbon dioxide is in the soda. So, the soda bubbles and releases carbon dioxide into the area above the liquid. When the soda is opened, the carbon dioxide increases the explosiveness of the eruption. 4 Another experiment that relates to this is to use similar liquids, and see if more or less concentrated carbonation increases the height. If the results agree with this experiment, then people would learn even more about Mentos eruptions.

References

1. Rachel Cutler and Emma Smith , Guilford Journal of Chemistry, Volume 1, Pages 6-8 (2007). 2. Justin Husted, Guilford Journal of Chemistry, Volume 1, Pages 19-20 (2007). 3. Mary Melillo and Artem Guryanov , Guilford Journal of Chemistry, Volume 2, Page 17-19 (2008). 4. Tonya Coffey, American Journal of Physics, Volume 76, number 6, pages 556 (2008). 5. Tonya Coffey, American Journal of Physics, Volume 76, number 6, pages 555-556 (2008). To view Coffey’s mentos physics article, check out this website: http://planck.lal.in2p3.fr/wiki/uploads/Photos/Activit%E9esClandestines/Coffey08_diet_coke_and_m entos.pdf

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Heating the 2l bottle of Diet Coke in hot water will increase the height of an eruption exponentially in the form of y=.57x-6.06, when x< or = 30 and y=-.16x+15.88 when x>30. Y=meters and x=temperature in Celsius.

This is why you need eye protection.

The eruption caused by combining mentos with coke is a commonly know occurrence, attempted by many, even appearing on the David Letterman Show 1 and in countless number of videos on YouTube. Yet even with such a fascination, almost no scientific publication has been made. In fact there is only one published documentation that speculates some answers. This knowledge provided by Dr. Coffey noted a specially important characteristic that has been utilized in this experiment. Heating the coke will produce a reaction capable of more mass loss 2 an observation confirmed by Justin Husted 5. Also, the study provided by Lauren Cutuli helped identify diet coke as the producer of the largest eruption 3. Combining this knowledge with the previous studies of Cutler and Smith, in which frozen mentos also yield a larger eruption 4, an even more powerful reaction can be constructed. In this experiment, the effects of heating coke in comparison to room temp will be studied. For entertainment value, frozen mentos have also been added but will remain constant.

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Experimental Procedure 1. Freeze the fruit mentos in a freezer set to -11.2 degrees Celsius for three days 2. On the third day place the 2l diet coke into a tub of hot water at a temp of 90 degrees Celsius. Leave in for 5 minutes (For control skip this step) 3. Place six frozen mentos into the Geyser Tube and insert into the top of the bottle. 4. Record height of the reaction 5. Repeat steps 1 through 4, 4 times 6. For testing the control do step 5 but skip step 2. 7. Boil water to 100 degrees Celsius and place coke in for twenty minutes 8. Set up Geyser tube with 6 mentos 9. Record reaction Safety Concerns: Heating the coke will create pressure inside the bottle capable of exploding. Always wear safety goggles when dealing with large eruptions to prevent anything getting in your eyes. Experimental Design: Six frozen fruit (assorted flavors) mentos are placed into the Geyser Tube. Once the tube is properly set up, one person opens the coke at the moment in which the experiment is to be done. Immediately the other person places the tube into the bottle. Results After the experiment the results concluded that as the temperature of the coke increased the height of the eruptions increased as well. When the coke was at room temperature the eruption went an average of 8ft in the air. While heated in almost boiling water and at 30 C it shot up to an average of 11 1/3 feet. However the results did not continue to sky rocket when the coke was heated to approximately 38 C, when the coke reached this temperature the pressure inside the bottle was to great and the bottle decided to expand into a more bulbous shape. So when as the mentos fell into the coke it erupted with such force that mist and only some coke came out. It did however last longer then the other cokes.

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Results (continued)

Height of eruption as a function of Temperature This table is just an example. 12 10

Height of Eruption (M)

8 2: Insert Graph Title Here Figure 6 4 2 0

Room Temperature (24 C)

Warm (30 C)

Hot (37 C)

Temperature of Coke

This graphis just an example.

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Conclusion Heating diet coke can increase the height of an eruption when until the water is heated in water within 7 degrees of boiling or any hotter as the heat provided by such high temperatures can create to much pressure to allow a steady stream. Instead the coke is forced out so violently that it makes a misty spray decreasing height. Getting a temperature about 7 degrees cooler than this will provide just enough to heat for the eruption to get a maximum height. Similar to Dr. Coffee’s and Cutler and Smith’s tests, adding heat to the coke has given more height. Therefore, the hypothesis that heating increases height was supported and the test has also determined heating too close to boiling will decrease height. Being such a quickly timed event in which mentos can quickly thaw and the coke cool down in the cold weather, as well as being unable to get a perfect measurement, there is a chance the data does not accurately project the true characteristics of a reaction involving frozen mentos and hot coke. Nonetheless, heating the coke will very noticeably increase the height by y=.57x-6.06, when x< or = 30 and y=-.16x+15.88 when x>30. Y=meters and x=temperature in Celsius. Using the basic principal that heating and object normally quickens the time needed for the reactants to yield results, the coke and mentos responds similar. The mentos being the necessary component to create a reaction, the heat served as a catalyst that speeded its combination with coke. Doing so would have created a reaction that happened quick enough to force more coke out at once. With this occurring, a higher pressure would have resulted in a higher reaction.

References

1. Tonya Coffey, American Journal of Physics, Volume 76, number 6, page 551 (2008). 2. Tonya Coffey, American Journal of Physics, Volume 76, number 6, pages 552, Table III (2008). 3.Lauren Cutuli, Guilford Journal of Chemistry, Volume 2, Page 30 (2008). 4.Rachel Cutler and Emma Smith, Guilford Journal of Chemistry, Volume 1, Pages 6-10 (2007). 5.Justin Husted, Guilford Journal of Chemistry, Volume 1, Page 19-20 (2007).

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Summary The Mentos and Diet Coke reaction is a popular experiment with not much officially known about it. With this particular experiment, we have discovered that solid Mentos cause the diet coke to erupt on average 3.6 meters higher compared to crushed Mentos which caused a 0.67 meter eruption. This paper also experiments on solid and powdered dishwashing soap and Alka-Seltzer tablets. The solid forms of the AlkaSeltzer was able to make an eruption 9.333% higher than its powdered counterpart, while the solid dishwasher soap had an eruption on average 4 times higher than in its powdered form. This experiment is not the kind of experiment that can create a logical mathematical formula to explain the results.

Whole mentos in diet coke caused a 4 meter eruption Introduction This popular reaction occurs when one drops Mentos into a Diet Coke soda, resulting in a eruption of soda spurting out from the nozzle of the bottle. It has been stated that when the Mentos are dropped into the soda, the arabic gum and other ingredients of the candy disrupts the water molecules in the Diet Coke and break the surface tensionยน. This explains the ferocious burst of soda that occurs when the Mentos meet the soda.

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Introduction (continued) The surface of the candy put in has also been proven to influence the eruption itself. Steve Spangler’s ‘nucleation site’ idea states that the Mentos’ surface has many little nooks and crannies for carbon dioxide bubble to form, and when the bubble form on the sunken candies, they push the liquid above it up, resulting in the eruption¹. In Carly Clark and Jenny Agamie’s lab dealing with the coating of the Mentos, it was concluded that Mentos with their coating got an average eruption of 230 cm whereas Mentos without their coating only got an average eruption of 33.33 cm, proving that the coat influences the height of the eruption². Another experiment by Hill and Gaboury showed that Mentos without their coatings created an eruption of 65 cm while Mentos with the coating got a 95 cm³ eruption. The form of the candy also influences the height of the eruption. The experiments preformed by Coffey show that Mint Mentos in Diet Coke caused a 15.3 ft eruption compared to the 1.0 ft eruption by crushed mentos⁴. However, contrary to these statements, many experiments have shown that when increasing the surface area of Mentos, by cutting them in half or drilling holes in them, yielded an increased height of eruption. Ring and Kipness’ experiment proved that Mentos sliced in the middle created an eruption 52 cm high compared to whole Mentos with 25 cm⁵. In Hill and Gaboury’s experiment drilling a 5mm hole in the Mentos, it was recorded that Mentos with the hole had an eruption of 120 cm compared to regular Mentos which had an eruption of 95 cm³. Our experiment will hopefully bring some light to this controversy of whether or not the Mentos produce higher eruptions crushed or whole. In our experiment, we will test the effect of solid Mentos versus crushed Mentos as well as solid Finish dishwashing soap versus powder dishwashing soap and whole Alke-seltzer versus crushed Alkeseltzer tablets to show that the solid shape of the product in the soda really has an effect on the eruption.

Experimental Procedure 1. Place 5 Mint Mentos, roughly 14 grams, into the Mentos nozzle. 2. Place a 1.5 liter Diet Coke on the ground and unscrew the cap. Quickly screw the nozzle. 3. Hold the bottle and pull the string on the nozzle. 4. Record the height of the eruption in meters. 5. Repeat for three trials each for the crushed Mentos (each particle would be roughly 1 cm in diameter), the solid Finish dishwashing soap blocks, powder Finish dishwashing soap, AlkaSeltzer tablets, and powdered Alka-Seltzer. For the powder and crushed trials, use the alternate nozzle on page 3.

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Left: Nozzle made from plastic binder divider, paperclip, and cardboard. Right: Nozzle in place in soda bottle top.

Cardboard Disk

Results Our results found during this experiment cannot be clearly shown through the use of a mathematical equation. Rather it is one which can be assumed based off of large differences in surface area. This large increase of surface area was shown through the crushing of the drop materials present in each experiment. In the experiments concerning solids, such as the Mentos, dishwasher soap tablets, and Alka-Seltzer tablets, the eruptions proved to be many times higher than that of their crushed or powdered counterparts. After crushing the Mentos to fragments, roughly 1 cm in diameter each, it was observed that the eruption height was tremendously lower. In solid form, one with less surface area, the eruption proved to be five times higher than when crushed. Likewise the experiments held for both the solid and crushed/powdered forms of Alka-Seltzer and dishwasher soap were drastically different in eruption height. The solid form of Alka-Seltzer, with an average eruption height of 2.8 m, clearly out did the powdered form which, while had a much longer eruption time only rose to about .3 m. In solid form the AlkaSeltzer was capable of erupting 9.333% higher. The eruptions caused by the solid dishwasher soap was also tremendously larger than that of the powdered form. As a solid the dishwasher soap was capable of making an eruption on average 2.1 m high, while as a powder on average it could only reach 0.5 m in height, the solid creating an eruption over four times the height of the powdered form. Guilford Journal of Chemistry

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Powder and Solid Reactions in a Soda Eruption

Trial 1

Trial 2

Trial 3

Average

Mentos

3.4 m

4.0 m

3.45 m

3.6 m

Crushed Mentos

0.35 m

1.06 m

0.609 m

0.67 m

Solid soap

2.0 m

2.1 m

2.1 m

2.1 m

Powder soap

0.5 m

0.457 m

0.457 m

0.5 m

Alka-seltzer

2.3 m

3.0 m

3.0 m

2.8 m

Powder Alkaseltzer

0.3 m

0.3 m

0.4 m

0.3 m

Powder and Solid Reaction in a Soda Eruption 4

Eruption height in meters

3.5 3 2.5 2 1.5 1 0.5 0 Mentos

Crushed Mentos

Solid Dishwashing Powder Soap Dishwashing Soap

Alke-seltzer

Crushed Alkeseltzer

Item dropped in

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Conclusion This Mentos and Diet Coke experiment dealt with the whole version of the product dropped in versus the powdered version of it and the resulting height of the eruption. We discovered that whole Mentos create an eruption 5 times as high as the crushed Mentos, with an average of 3.6 meters versus the crushed Mentos with 0.67 meter of height. The solid dishwashing soap block had an eruption 4 times as high as the powder version, with 2.1 meters versus 0.5 meters, and the whole Alke-seltzer tablets had an eruption 9 times as high as crushed tablets with 2.8 meters versus 0.3. These result contradict those from the Hill and Gaboury paper and the Ring and Kipness paper, both which discussed how crushed versions of the Mentos created higher eruptions. However, these results also echo the work of Coffey, who achieved similar results for her crushed Mentos versus whole Mentos. With this experiment, we can safely conclude that the wholeness of the product dropped in does contribute to the height of the soda eruption. This result is likely so because, as explained by Spangler, the surface of the Mentos has many nooks for carbon dioxide bubbles to form and push up the soda¹. With a crushed Mentos, there would be less surface for these bubbles to form, therefore making the eruption less dramatic. The fact that the Mentos and other objects are whole also allows them to fall through the soda with less vicious drag, as shown discussed in Coffey’s report⁴. Both of these factors cause the whole Mentos, soap, and tablets to create higher eruptions than if they were powdered, having less surface to form carbon dioxide bubble and falling through the soda slower. A good follow-up experiment to test would be the measure the fall times of these products in comparison to their eruption height. There could have been some errors in the experiments tested. For example the alternate nozzle effected the accuracy of the experiments using it because the cardboard would sometimes not turn. An improved version of this, perhaps using plastic as the disk in the middle, would create a more reliable tool for the experiments.

References 1. Steve Spangler, “Mentos Diet Coke Geyser”, (2008). Can be found at www.stevespanglerscience.com/experiment/00000109. 2. Carly Clark and Jenny Agamie, Guilford Journal of Chemistry, Volume 1, pages 17-18 (2008). Experiment dealing with Mentos with and without their coating. 3. Nick Hill and Kyle Gaboury, Guilford Journal of Chemistry, Volume 2, page 38 (2008). Deals with drilling holes in Mentos to get a higher eruption. 4. Tonya Coffey, American Journal of Physics, Volume 76, number 6, page 552 (2008). 5. Emily Ring and Kipness, Guilford Journal of Chemistry, Volume 2, pages 38 (2008). Read this for the experiment dealing with slicing Mentos in half compared to whole Mentos.

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Summary When a Mento is left whole, it erupts exponentially higher than when it is cut or crushed. Five Mentos left whole exploded to a maximum height of 7 meters; five Mentos cut in halves exploded a maximum height of 2.3 meters; five Mentos cut in quarters exploded a maximum height of 3.2 meters; and five crushed Mentos exploded a maximum height of 3.6 meters. A formula that states this discovery is 21.5x 3-20.3x2+2.2x+3.6. By replacing X with the amount of Mento in one slice (1, .5, .25, .01, etc) it is possible to find out how high any sized slices would erupt.

2L bottle of diet coke with 5 whole fruit Mentos

Diet Coke and Mentos Eruption

Introduction

The Mentos eruption is a physical reaction between diet-coke and Mentos. For many years, this fascinating and you-tube popular experiment has been leaving experimenters and scientists wondering what exactly caused the explosion. As students of Dr. Brielmann’s chemistry class, we have been challenged to discover the scientific explanation behind the eruption. Only a few scientists have come close to an explanation for this unsolvable issue. One scientist Ms. Tonya Shea Coffey researched the topic and tested many different variables that would effect the height of the explosion. One experiment was the testing of the pH of diet-coke before the reaction and after. Before the reaction the pH was 3.0 and after it was also 3.0. This showed that the Mentos eruption is not one of acid-based.

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Another variable she tested was contact angle measurements to calculate minimal work of the water droplet to find whether seltzer, diet-coke, or coke was best for the experiment. The bubble with the lowest angle required less work, thus more explosive. Aspartame was found to be the most explosive, it also happens to be a major ingredient in diet-coke rather than coke. She also discovered that caffeine does not affect the height of the eruption. (2) Others found that the temperature of the Mentos both hot and cold

increased the explosion. (5) This knowledge of factors in a Mentos eruption revealed to our team that we wanted to perform an experiment focused on the different surface area of a Mento. Coffey found that, “If the bubbles must travel farther through the liquid, the reaction will be more explosive. Longer distances traveled by the bubbles resulting in a more explosive reaction also partially explains the differences in explosive power for whole Mentos in contrast to crushed Mentos; the smaller particles of the crushed Mentos fall through the liquid more slowly.� (2) Therefore, we built our experiment on the idea that Mentos cut in half, quarters, crushed and finally whole would reach the highest explosion. In the Guilford Journal of Chemistry, a similar experiment revealed that the crushed Mentos reached the lowest height. We disagreed with their results because the crushed had a longer distance to travel thus a bigger explosion. (3) Another experiment found that Mentos sliced in half would have the highest explosion. We also disagreed with their results because we found that Mentos cut in half had the lowest

explosion. (1) Similar to an experiment of previous students we aimed for the highest eruption. (4)

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Experimental Procedure 1.

2. 3. 4. 5. 6.

7.

Obtain two packs of fruit Mentos, four 2L bottles of diet coke, a Mentos geyser tube, scissors, optional measuring stick and safety goggles. Find an outdoor location so there is no mess to clean up, and preferably near a building so it is easier to measure the explosion. Leave five Mentos whole, cut five Mentos in halves, cut five Mentos into quarters, and completely crush five Mentos. Stack the five whole Mentos inside the geyser tube. Quickly unscrew the cap of the diet coke bottle, and screw the geyser tube on. Have one person hold the coke bottle upright, while another person pulls the trigger pin. Stand back and record the height (in meters) the coke erupted, using the building and/or measuring stick as a measuring guide. Note any oddities, such as a long wait for the eruption or the coke spraying to the sides. Repeat procedures 3-6 for the halved, quartered, and crushed Mentos.

Safety: • Always wear safety goggles when performing this experiment • Stand clear of the exploding coke • Do not eat Mentos and drink coke immediately after, or you will explode too.

Results For the first trial, five whole fruit Mentos were placed in the geyser tube over a 2L bottle of diet coke. The time between the removal of the cap and the addition of the geyser tube was approximately five seconds. When the trigger pin was pulled, it took approximately two seconds for the coke to erupt. The coke reached a maximum height of 7 meters, and the diameter of the eruption was about 3 cm. For the second trial, five halved fruit Mentos were placed in the geyser tube over a 2L bottle of diet coke. The time between the removal of the cap and the addition of the geyser tube was approximately five seconds. When the trigger pin was pulled, it took approximately two seconds for the coke to erupt. The coke reached a maximum height of 2.3 meters, and the diameter of the eruption was about 1 meter. For the third trial, five quartered fruit Mentos were placed in the geyser tube over a 2L bottle of diet coke. The time between the removal of the cap and the addition of the geyser tube was approximately five seconds. When the trigger pin was pulled, some of the Mentos pieces stuck to the sides of the geyser tube. It took at least five seconds for the coke to erupt. The coke reached a maximum height of 3.2 meters, and the diameter of the eruption was about 2 meters. For the last trial, five crushed fruit Mentos were placed in the geyser tube over a 2L bottle of diet coke. The time between the removal of the cap and the addition of the geyser tube was approximately five seconds. When the trigger pin was pulled, all the crushed Mentos stuck to the sides of the geyser tube. After jostling the tube a bit, some of the Mentos pieces fell into the coke, but other ones still stuck to the sides, blocking some of the eruption. It took 2-3 seconds for the coke to erupt. The coke reached a maximum height of 3.6 meters, and the diameter of the eruption was about 2 meters. Guilford Journal of Chemistry Volume 3 September 2010 3

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Results (continued)

Figure 1: Size of Mentos Pieces Versus Eruption Height Size of Pieces

Whole (1)

Halves (.5)

Quarters

Crushed

(.25)

(.01)

Eruption Height

7m

2.3 m

3.2 m

3.6 m

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Conclusion In the height comparison of Mentos eruptions it was found that five of the unmodified candies erupted to the height of 7 meters, five candies cut in half erupted to the height of 2.3 meters, five candies cut into quarters erupted to the height of 3.2 meters, and five crushed candies erupted to the height of 3.6 meters. Our data shows that the unmodified candies cause the biggest eruption, and the candies cut in half cause the smallest eruption. Our data proves that the discovery of Ring and Kipness (1) is not correct. Their data shows that Mentos candies cut in halves erupt higher than whole Mentos. Our data safely concludes that whole Mentos erupt about 2/3 higher than a Mento cut in half, and these halved Mentos make the smallest eruption. The halved, quartered, and crushed Mentos also erupt at about the same height. Our data is tight except for the fact that the quarter and crushed Mentos were not cleanly sliced. So therefore if you were to do the experiment again the surface area can be different which could affect the outcome of the data. Also the crushed Mentos got caught in the tube that drops them in. This delayed when they dropped and the speed of their fall. The amount of Mentos was kept consistent through out the experiment and so was the type of soda and condition of the soda. The formula derived from our results is 21.5x3-20.3x2+2.2x+3.6. This formula was derived by setting up a T-chart with X and Y as the headings. The numbers 1, .5, .25, and .01 were put in the X column corresponding to the sizes of the Mentos, and the corresponding heights were placed in the Y column. From here, the numbers were plugged into a cubic regression. By plugging the percentage of one Mentos slice in as X (for example, if Mentos are cut into eighths, plug in 1/8 as X), it is possible to tell how high any Mentos cut into pieces will explode. On a molecular level, it is unknown exactly why whole Mentos erupted so much higher than cut or crushed ones. Perhaps the coating is a factor. When the Mentos were left whole, the coating was left alone; but when the Mentos were cut or crushed, parts of the coating crumbled. Though we tried to save as much of the coating as we could when cutting the Mentos, it was not possible to preserve the entire thing. If a molecule in the Mentos coating reacted in an explosive way with the ingredients in the diet coke, this would explain why the whole Mentos erupted so much higher than the cut and crushed ones. After observing how the crushed Mentos had a late fall and slower fall into the soda, it would be interesting to test that. In another experiment the delay of the fall and the speed of the fall can be tested to see how it affects the height of the eruption. For this experiment the delay of the drop time would have to be timed and the speed of the fall would have to be measured.

References 1. Emily Kipness and Emily Ring, Guilford Journal of Chemistry, Volume 2, Page 38 (2008). 2. Tonya Coffey, American Journal of Physics, Volume 76, number 6, pages 551-337 (2008). 3. Nick Hill and Kyle Gaboury, Guilford Journal of Chemistry, Volume 2, Page 38 (2008). 4. Aaron Davis and Travis Dillon, Guilford Journal of Chemistry, Volume 1, Pages 17-18 (2007). 5. Steffi Marsh and Taylor Smith, Guilford Journal of Chemistry, Volume 1, Pages 17-18 (2007).

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The Height of the Reaction Between Mentos and Diet Coke Decreases When the Shape of the Mento is Changed by Rachel C. and Rachel M. Submitted October 5, 2010 Accepted For Publication October 6, 2010

Summary We wanted to see if the shape of the Mento affected how high the reaction was. We modified the Mentos by heating them until they were soft and then shaping them into one of several shapes. We thought the different shapes might provide some different qualities like surface area and how fast they dropped into the soda. However, we found that shaping the Mentos caused a significantly smaller eruption and therefore negatively affected the excitement of a Mentos and Diet Coke show. Note: Our type of experiment was not applicable to any type of mathematical formula.

Mentos and Diet Coke Eruption

Introduction The Mentos eruption is most commonly classified as the reaction between Mentos candies and Diet Coke; however, new discoveries have been made by simply altering an aspect of these ingredients or by changing them entirely and observing their effect on the reaction. Although there have been numerous experiments regarding the state of the Mentos candies versus the height of the eruption, there have been no results found on the effect of the shape of the Mentos on the reaction.

In order to understand the modifications made to the original experiment, and what they have determined, you must understand the experiment in its most basic form 1. The Mentos and Diet Coke reaction is a physical reaction; it has nothing to do with acids and bases 2. However, the actual ingredients within both substances do have a great deal of importance. Potassium benzoate and aspartame allow bubble formation, which permits carbon dioxide to escape into an eruption 3. The eruption’s height and intensity depends upon the concentration of these ingredients (higher concentration being greater) 4, the roughness of the candy (rougher surface is better) 5, the speed in which the sample falls through the liquid (faster being greater) 6, and the temperature of the Mentos and Diet Coke being used.

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Introduction (continued) We set out to find if the shape of the Mint Mentos would affect the reaction, as our interest was sparked by the fact only the Mentos state, temperature, roughness, and coating had been looked upon in previous experiments. It became questionable if the different shape would impact roughness and the speed traveled through the Diet Coke so that the eruption was greater. It had already been determined that by cooling the Mentos, the eruption is significantly higher than if they were left at room temperature 7 and that the normal coating of Mint Mentos reacted better than other substitutes 8. Another experiment having due to do with alteration of Mentos was where a 5 mm hole was drilled in the center of the Mentos; the eruption was twenty percent higher, which shows that the eruption can be changed by altering structure 9. Though these experiments are relatable, we set out to determine if the shape of the candy could be altered in such a way that temperature, coating, surface area, and roughness remained most beneficial. If the shape was changed in a way that was better than the normal circle it would be an astounding discovery and improvement to the Mentos and Diet Coke reaction.

Materials 10 12oz Bottles of Diet Coke 30 mint Mentos 1 Geyser Tube Meter stick Safety goggles Microwave Cup Rolling pin Container Refrigerator

Variables Control: Regular Mentos Dependent Variable: Height of the Reaction Independent Variable: Shape of the Mento Constant: Temperature of soda, temperature of mentos, time soda was open before reaction, time mentos refrigerated, size of the bottle, type of soda, type of mento, mass of mento

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Experimental Procedure 1. Gather all materials, put on gloves, and set up flat station where candies can be shaped. 2. Place three Mentos into glass plate, so that they are lying flat and have a few centimeters in between them. 3. Place the plate in the microwave on high power for thirty seconds, stopping the microwave in 10 second increments. Simply open the door briefly (5 seconds) and then close and restart. 4. Once the thirty seconds are up, remove the plate and bring to station. Use your hands to remove the candies and to mold them into specific shape/form (sphere, cube, string, or rolled). 5. Repeat 2-4 until Mentos are completed for all trials and replicates. Control group (Mint Mentos) will remain the same. 5. Place all Mentos into container and place container in refrigerator for 96 hours (4 days). 6. One the time is up Mentos may be removed from trays and brought to testing site, where Diet Coke is set up against a measurable wall. Wall should be marked or have some system of measuring the height of the eruption of reaction. 7. Begin trial by adding three Mentos of one shape/form to dropper. The dropper should be attached to the top of Diet Coke bottle (12 ounces) so that once the string is pulled, the candies will enter opened bottle efficiently. 8. Pull the string and release Mentos into the Diet Coke. Record the eruption on a video camera and determine the highest point the soda reached using meter stick. 9. Repeat steps 7-8 until all trials have been tested. Data and notes should serve to make conclusions.

Safety Precautions This experiment requires that Mint Mentos are heated until soft and able to be formed into various shapes. For this reason a microwave is used in three ten second increments on high power for each of the candies. As with any heat source, be sure to be cautious about burning yourself. Melt the candies only in glassware and use gloves to remove and relocate dish for shaping. Gloves should be worn to shape the candies as well, as the candy is extremely hot within and very sticky. Also, when adding the Mentos to Diet Coke it would be advisable to wear safety glasses and adjust the bottle’s nozzle so that it is not directed towards the face. Failing to do so could result in having some of the liquid spray into your eye or being hit when the reaction occurs.

Results In this experiment, we found that the shape of the Mentos negatively affects the height of the reaction. The control had the highest reaction with an average of 107.5 cm. The rolled Mentos caused the next highest reaction with an average of 68.5 cm. The cubes were next with a 63.5 cm average. The second lowest was the sphere shaped Mento with an average of 52.5 cm and the lowest was the string with a 35 cm average. The shaped Mentos caused a reaction that were all about the same foaminess and lasted for the same length of time. Overall, changing the shape of the Mento was very detrimental to the height of the reaction.

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Results (continued) How the Shape of the Mentos Effected the Height of the Reaction Trial 1

Trial 2

Average

Control

96 cm

119 cm

107.5 cm

Sphere

60 cm

45 cm

52.5 cm

Cube

67 cm

60 cm

63.5 cm

Rolled

57 cm

80 cm

68.5 cm

String

35 cm

35 cm

35 cm

How the Shape of the Mentos Effected the Height of the Reaction

120 100 80 Trial 1

60

Trial 2 Average

40 20 0 Control Sphere Cubes

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Conclusion We were able to conclude that changing the shape of the Mentos is detrimental to the height of the eruption. All of the shaped Mentos caused a significantly lower eruption when compared to the control. This is most likely because the outer shell of the Mento was broken and rearranged. The Mentos had broken fragments of their shells inside of them instead of on the outside where they could easily react with the Diet Coke. The Mento filling probably does not dissolve too much in the Diet Coke, so anything encased in the filling would not be able to react with the Diet Coke. In our experiment, we made several errors that should be fixed in a later experiment. First of all, not all the Mentos of the same shape were the exact same size, proportion, and even the mass may have been slightly different. This would affect how much Mento ingredient was able to react in each case. Another error was the fact that the string shaped Mentos were dropped in the geyser tube with out the nozzle on top unlike the others because they had to be forced down with a pencil. This means the height of those reactions were probably smaller because the hole at the top was bigger than the other trials. The last error we thought of was the fact that we had no extremely accurate means of measuring the height of the eruptions so the data could be slightly off. If we were to do a future experiment, there would be a few changes. The first suggestion would be to put the Mentos in molds, or preferably made so that the filling was all encased in the outer shell. This would eliminate the size/shape error and might produce better reactions because the outer shell would be on the outside. This would also allow a scientist to be able to calculate the surface areas of the shapes. This could produce results that could be represented with a mathematical formula. We would also do many more trials in a future experiment to be sure all the results were accurate. Overall, this experiment was slightly successful, but could be improved much more to come up with more conclusive data.

References 1

Tonya Coffey, American Journal of Physics, Volume 76, Number 6, Pages 551-557 (2008). Read page 552 of Coffey's paper (see reference 1) for a detailed analysis of the effect of pH on the height of a Mentos eruption. 3 Read page 554 of Coffey’s paper (see reference 1) for explanation of aspartame and sodium bicarbonate’s involvement in the reaction. 4 Read page 1 of Coffey’s paper (see reference 1) for statement on concentration of Mentos. 5 Read page 556 of Coffey’s paper (see reference 1) for detailed analysis on how surface roughness has an impact. 6 Read page 555 of Coffey’s paper (see reference 1) for detailed analysis on how the speed the sample falls through liquid impacts reaction. 7 Rachel Cutler and Emma Smith, Guilford Journal of Chemistry, Volume 1, Pages 6-8 (2007). 8 Carly Clark and Jenn Agamie, Guilford Journal of Chemistry, Volume 1, Pages 17-18 (2007). 9 Nick Hill and Kyle Gaboury, Guilford Journal of Chemistry, Volume 1, Page 38 (2008).

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Caffeine has a profound affect on the enhancement of the caliber of the eruption of the diet coke and mentos eruption

Summary Throughout this experiment, it has become abundantly clear that the caffeine in the coke plays a very important part in the entire chemical process. By comparing the height of the eruptions of the diet coke with caffeine against that without caffeine, it could be clearly seen that the coke with the caffeine had a much more spontaneous eruption. This reveals that the caffeine in the coca cola acts as a catalyst, creating a spontaneous eruption within the bottle and pushing up the coke out the small nozzle, which creates the eruption. Without this caffeine, the eruption was a little less than 1000% less dramatic, hardly even leaving the tube which the eruption was launched from. The coke without the caffeine averaged around 0.4 meters, an incredibly insignificant eruption compared to the coke with the caffeine, which averaged out to around 3.8 meters.

Eruption of Coke and Mentos!!!

Introduction This experiment was performed in order to test whether or not the absence of caffeine in diet coke would have an affect on the height of the eruption. We used mint mentos as a constant, in order to better isolate the variable of the caffeine in the experiment. By viewing other experiments, it is shown that diet coke and mentos have a significant eruption on it’s own, but it is still to be determined what causes this extreme eruption within the coke. In order to better understand this phenomenon, we decided to take out the caffeine element within the solution, which has a chemical structure of C8H10N4O2, and see if that might have played a pivotal role in the eruption. Since caffeine is commonly used as a stimulant in nature, for example in coffee to give people that extra edge and stimulate them at least temporarily, we hypothesized that it might have been an essential component to create the fast paced eruption which is seen in the coke plus mentos eruptions.

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We preformed three separate trials in order to acquire more accurate averages. Also we kept the type of mentos (Mint) and size of the bottles (26 fl oz) constant, all to further the validity of this experiment and try to eradicate troublesome variables which could invalidate our results. We chose this as the experiment because it seemed as though caffeine would be a relatively simple, yet incredibly vital element to isolate, and because it does not apply only to diet coke. If it could be determined that caffeine is the element, or at least a vital one which affects the eruption size of caffeine, it can by hypothesized that very similar results could be determined for other soft drinks which contain little to no caffeine.

Experimental Procedure Step 1: Gather materials needed for the experiment: Diet Coke (3), Diet Coke without caffeine (3), eruption tube, mentos (18), and Safety Goggles Step 2: Set up the area for eruptions. Preferably an area far away from other people to prevent injuries, and somewhere that the eruption of coke cannot ruin anything Step 3: Open one of the diet cokes, and quickly but cautiously apply the eruption tube with three mint mentos in it on the top of the coke. Step 4: Place coke in the designated area, and pull the cord, retreating from the eruption to prevent injury. Step 5: Record the height of the eruption Step 6: Repeat steps 3-5 two more times Step 7: Repeat steps 3-5 three more times, this time using diet coke without caffeine Results The results of the diet coke without caffeine was rather dull. Although this was expected, the low caliber of the eruption was almost disappointing, since the first eruption hardly got a reading of .2 meters. The second was slightly higher, at around .6 meters, and the third coming up at a whopping .5 meters. The average height of these three eruptions came out to be around .43 meters. In very stark contrast with this very similar soda, the diet coke with caffeine erupted to about 3.7 on its first go. After that, it shot up even higher barely passing the 4 meter marker at around 4.1 meters. Finally, the last one came up a bit shorter at around 3.6 meters. In addition to this, the mentos which were placed within the diet coke bottles with the caffeine were heavily scarred, showing that they reacted on at least a physical level with the diet coke. The same could not be said for the mentos that were dropped into the diet coke without caffeine, for they could be seen sitting at the bottom of the coke bottle even after the initial slight eruption, almost completely intact.

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Results (continued)

Affect of Caffeine on the height of the eruption of diet coke and mentos Diet Coke

Diet Coke without Caffeine

Trial One

3.7 m

0.2 m

Trial Two

4.1 m

0.6 m

Trial Three

3.6 m

0.5 m

Averages

3.8 m

0.433 m

The affect of Caffeine on the height of the eruption of diet coke and mentos 4.5 4

Height (meters)

3.5 3 2.5

Diet Coke Diet Coke without Caffeine

2 1.5 1 0.5 0 Trial One

Trial Two

Trial Three

Averages

Trials

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Conclusion Caffeine can be shown by this experiment to be a vital role in the coke and mentos eruptions. Even though this experiment does not eliminate the possibilities that other factors within the coke might play a role in the eruptions, it can be seen that when you take out the caffeine, the eruption height depreciates greatly. This has not been the first experiment which has shown that affects of caffeine on the height of the eruptions. Other experiments which have compared other kinds of sodas to diet coke have shown that sodas with less caffeine such as fresca (No caffeine) have insignificant eruptions when compared to diet coke (1). If this experiment was to be tried with higher volumes of soda, the results should remain very similar to the ones shown here. This is based upon the findings that “the volume does not have an affect on the mentos eruption.” (2). There is of course room for error within the trial. There were many variables which might not have remained constant throughout the experiment which have been proven to have affect on the height of the eruption, such as the heat of the soda which could have fluxuated from bottle to bottle(3), and temperature of the mints, which had been stored in different conditions prior to being used. (4) Human error also plays a role in every experiment. The particular part of human error which affected us the most was the quality of the mentos. Some of them were broken, since they were dropped a few times before the experiment took place. None of them were too bad, but the quality of the mentos’ physical state has been proven to have an affect on the height of the eruption, which is why this data might be slightly off. (5) The reason why we believe that the results were what they were, was that the caffeine in the soda acted as a stimulant, similarly as to how it does in caffeinated beverages. It is probably caffeine ability to release ATP, which is basically molecular energy, which causes it to make the eruption of the coke so spontaneous and thus producing a much larger eruption than normal.

References 1. Angelise Musterer Lindsay Ruotolo, Guilford Journal of Chemistry, Volume 2, Pages 12-13 (2008). 2.Kaitlin Earles and Megan Graham, Guilford Journal of Chemistry, Volume 2, Page 22 (2008). 3.Justin Husted, Guilford Journal of Chemistry, Volume 1, page 21 (2008). 4. Rachel Cutler and Emma Smith, Guilford Journal of Chemistry, Volume 1, Pages 6 (2008). 5. Alex Jagielski and Eric Hedberg, Guilford Journal of Chemistry, Volume 2, Page 38 (2008).

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Summary We decided to conduct an experiment to test the physical changes of mentos. One test was made up of three regular solid mentos added to a coke which resulted in the highest fastest explosion. The second test was three crushed mentos which was a slower lower explosion than the solid, and the third test was three liquidized mentos which was the slowest and lowest of all three trials. The mathematical formula we used to display our results was 3M/C=D where M= mentos, C= physical change of the mentos, and D=distance of explosion. Our results show that when a mentos undergoes physical change the height of an eruption decreases dramatically.

Second Day: conducting the regular and crushed mentos trials.

Introduction In this experiment we tested the physical state of mentos and how it relates to the eruption height of the coke. We used regular coke instead of diet which most likely had an effect on the eruption heights. Experiments have been executed to test the effects of different sodasยน and diet coke has proven most effective when paired with fruit mentos. In this experiment we used mint mentos instead.

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The height of the mentos and coke eruption has been said to be affected by many factors such as soda type, candy flavor, or ingredient roughness¹. Others have tested nozzle sizes, and ingredient temperature². In the Guilford Journal of Chemistry volume II an experiment was done on the effect of the physical state of mentos, whole, crushed, and cut in half² and how it affects the height. It was found that the mentos that were sliced in half caused a larger eruption, 58cm followed by the crushed mentos, 35cm and finally the whole mentos, 25cm. The experiment tested the surface area of the mentos whereas this experiment will incorporate a liquid mentos as well. An experiment was conducted on the speed at which a substance falls through the liquid and how it affects the height of the eruption⁵. It was said that a crushed mentos will fall through the coke more slowly and therefore it will cause a smaller eruption. This is due to the fact that the farther the bubbles caused by the mentos have to travel, the larger the eruption will be. Because the crushed mentos fall slower the bubbles will have less distance to travel and so the eruption will be less spectacular. In the Guilford Journal of Chemistry volume I, an experiment was conducted to test the effects of the temperature of mentos on the height of eruption³. It was discovered that mentos frozen to 263K had a greater effect on the eruption, resulting in a height of 350cm. The mentos warmed to 313K resulted in a lower height of 200cm followed by a room temperature height of 30cm. The temperature of the mentos clearly had an effect on the height of the eruption however, it was the cold and not the warm mentos that made the largest explosion. Many experiments have been executed on the factors that influence the height of an eruption. Students have tested many different variations of the mentos and coke eruption in the Guilford Journal of Chemistry volume I³ and II². In this experiment the effects of the physical state of the mentos on the height of the eruption will be tested. The experiment will consist of three states, whole, crushed, and liquid. Each state will consist of three mentos dropped into a 592mL bottle of coke and the heights will be recorded and compared. Materials - Three 591mL bottles of coke - 2 packs of mint mentos - Geyser tube⁴ - Mortar and pestle - Plastic bag - Microwave - Pot - Hot plate - Thermometer - Tweezers - Scissors - Meter stick - Camera - Safety goggles

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Procedure 1. Bring all materials outside 2. Put on safety goggles 3. Insert 3 mint mentos into the geyser tube, leave the tube’s cap off 4. Remove the cap from one 591mL bottle of coke 5. Quickly secure the tube to the top of the coke 6. One person hold the bottle at arms length and the other hold the string 7. Carefully pull the string, allowing the 3 mentos to fall into the coke 8. Record the estimated height of the eruption 9. Crush three mentos into small pieces using a mortar and pestle 10. Open a bottle of coke and secure the geyser tube to the top 11. Remove the tube’s cap and carefully pour the mentos into the coke 12. Step back and record the height of the eruption 13. Heat a small pot of water to 105˚C 14. Place 3 mentos in a plastic bag 15. Place the bag in the microwave for one 30 second period and one 20 second period 16. Carefully place the bag into the hot water 17. Leave the mentos in the water until they have turned completely to liquid 18. Remove the cap from a coke bottle and attach a geyser tube 19. Pinch the top of the bag using tweezers and lift it out of the water 20. Make sure all of the liquid mentos is in one corner of the bag 21. Carefully carry the bag to the coke so the corner is directly over the opening of the tube 22. Using scissors, cut the corner of the bag so the mentos pour into the coke 23. Step back and record the results

Results

As we conducted each trial we recorded our data and made sure to note the height and time it took for the coke to erupt. For our constant, we used three solid mentos that had not been altered or changed and, when dropped into a regular coke through the geyser tube4, the explosion was immediate and the height was 80cm . In the next test, we crushed the mentos and poured them into the coke resulting in an explosion that was slower and the height was 50cm. For the last trial we heated the mentos up until they turned to a clear, gooey liquid and poured them into the coke. This explosion was the slowest of all three mentos experiments, and the height was 30cm. We observed that the more we altered the mentos the lower and slower the coke eruption would be. Many experiments have been conducted testing the height of the explosion and the factors that influence it, shown in Guilford Journal of Chemistry volume I³ and II². The mathematical equation we used to display our data was 3M/C=D where the M represents three mentos, the C represents the physical change of the mentos, and the D represents the distance of the explosion . The more we changed the mentos the lower the distance was, resulting in a decreasing reaction with the coke. Every time the three mentos are divided by the increasing change to the mentos, the distance in height from the explosion diminishes.

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Results (continued) Use all the space you need. Include your table and chart- you can move things around as you like. Figure 1: Insert Table Title Here

This table is just an example.

Figure 2: Insert Graph Title Here

This graphis just an example.

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Conclusion Our results show significant data that displays information about the mentos/coke explosion. We assume that the reason for the solid mentos to have the highest eruption is because the candy is able to sink to the very bottom of the coke, thus more coke is able to explode because it is above the candy. The crushed mentos do not sink all the way to the bottom, resulting in a small amount of the coke that becomes reactant. With the liquid mentos, the explosion was the lowest because the candy immediately dissolved into the coke resulting in only a small amount of the coke was affected. The C02 dissolved in the coke is released faster and easier by the solid mentos, where in contrast, the liquid and crushed mentos dissolve much faster than a solid mentos, resulting in less C02 being released. We would encourage future studies on this experiment and suggest that, if it were to be repeated, try to conduct all experiments on the same day in the same environment. Keep the cokes constant and repeat the trial at least three times so that the results will be more conclusive. We had to melt the mentos inside, so one of the experiments needed to be tested inside. If there was a way to repeat this outside, the lab would have a greater effect because all of the trials would be in the same environment. In the Guilford Journal of Chemistry volume II an experiment was done on the effect of the physical state of mentos, whole, crushed, and cut in half² and how it affects the height. It was found that the mentos that were sliced in half caused a larger eruption, 58cm followed by the crushed mentos, 35cm and finally the whole mentos, 25cm. These results contradict our data in some aspects, where they found that a crushed mentos caused a larger explosion than a whole mentos, when we found the exact opposite. Our data shows that the crushed mentos reaction creates a slower and less high explosion than the whole mentos eruption. The mathematical formula we used to display our results was 3M/C=D where M= mentos, C= physical change of the mentos, and D=distance of explosion. Our results show that when a mentos undergoes physical change the height of an eruption decreases dramatically. The higher the percent of change subjected to the mentos , the lower the coke explosion would be.

References 1 Tonya Coffey, American Journal of Physics, Volume 76, number 6, pages 552553 (2008). 2 Emily Ring and Emily Kipness, Guilford Journal of Chemistry, Volume 2, Page 38 (2008). 3 Rachel Cutler and Emma Smith, Guilford Journal of Chemistry, Volume 1, Pages 6-8 (2007). 4 "Geyser Tube." Science Projects Experiments, Educational Toys & Science Toys. Web. 02 Oct. 2010. <http://www.stevespanglerscience.com/product/geyser-tube>. 5 Tonya Coffey, American Journal of Physics, Volume 76, number 6, page 555 (2008).

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Mentos Eruptions Increase Over 10 % When 4 Packets of Aspartame Are Added By Erin M and Barbara S Submitted October 5, 2010

Summary

We added additional aspartame to Regular and Diet Coca-Cola along with mint Mentos to see if the combination would cause the eruption to be higher, instead of just adding Mentos. We added either two or four packets of aspartame and three Mentos to the Coca-Cola, and the aspartame did cause the eruption to go higher.

Example of Mentos Eruption

Introduction

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The Diet Coke and Mentos reaction occurs when new Mentos are dropped into a fresh bottle of Diet Coke and results in a jet of Diet Coke spray shooting out of the bottle1. The experiment performed was a test to see if added aspartame to regular Coca-cola and Diet Coke would cause the eruption to go higher. When added, the aspartame itself caused a small eruption where the soda fizzed, bubbled and spilt over. Aspartame is an active ingredient in this eruption, along with potassium benzoate, but was proven in an experiment to produce a greater loss of mass than potassium benzoate, causing it to be the primary cause for a high eruption2. As proved in Mythbusters, aspartame is a key ingredient in the Diet Coke-Mentos eruption3. The reason for this ingredient causing a bigger eruption is because the bubble formation doesn’t require as much work, which allows CO2 to quickly leave from the soda4. The reaction of the aspartame with the Mint Mentos and soda is what allowed the eruption to become greater than just an eruption involving soda and Mentos itself. The addition of more Mentos also has a direct effect on the stream that erupts from the bottle. It is concluded that the more Mentos that are added, the higher the stream5. With the addition of three Mint Mentos and aspartame to regular Coke and Diet Coke, it allowed for a higher eruption because of all the active ingredients that worked together.

Experimental Procedure 1. Gather materials 2. Take 1 12 oz bottle of regular Coca-cola 3. Put 3 Mint Mentos into the geyser tube (make sure the stick is in the bottom before you add them) 4. Screw on the top of the geyser tube 5. Screw the geyser tube tightly onto the top of the bottle 6. Pull string and RUN 7. Measure height 8. Record data 9. Repeat steps 2-8 two more times 10. Repeat steps 2-9, using Diet Coke 11. Take 1 12 oz bottle of regular coke 12. Do steps 3-5 13. Take 2 packets of aspartame and carefully pour them into the hole on the top of the geyser tube 14. Do steps 6-9 15. Do steps 11-14 using Diet Coke 40


16. 17. 18. 19. 20.

Take 1 12 oz bottle of regular coke Do steps 3-5 Take 4 packets of aspartame and carefully pour them into the hole on the top of the geyser tube Do steps 6-9 Do steps Do steps 16-19 using Diet Coke

Conclusion

By doing this experiment, it can be safely concluded that by adding aspartame to soda, it increases the height of the eruption. The data gathered varies a lot from the trials done, though no trial was done more than once because of lack of sufficient time. For example, Regular coke initially decreased in height when two packets of aspartame were added, but then increased when four packets were added. It decreased by 0.25 meters with two packets and then increased by 0.15 with four packets. For this experiment, a mathematical equation can be used. For Diet Coke it would be Height=1.2m (number of packets aspartame added, or just P), and for regular Coke the data gathered was too askew to make a reliable formula. All together the formula shows that the height of the eruption and number of aspartame packets are proportional, so the overall formula would look like H1 over P1 equals H2 over P2, for example: 3/1=6/2. According to this formula, if the experiment was extended and 6 or 8 packets of aspartame were added instead, then the likeliness of the eruption going higher is very probable. The reason for all these results is due to the fact that aspartame is a key ingredient in the eruption sequence, and the experiment increases the amount of aspartame in the soda used, causing the eruption to be higher. A follow up experiment to this could be to either try different trials with more packets of aspartame, more Mentos, or a larger bottle of Coke and Diet Coke.

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References

1. 2. 3. 4. 5.

Tonya Coffey, American Journal of Physics, Volume 76, Page 551 (2008). Tonya Coffey, American Journal of Physics, Volume 76, Page 554 (2008). Tonya Coffey, American Journal of Physics, Volume 76, Page 553 (2008). Tonya Coffey, American Journal of Physics, Volume 76, Page 556 (2008). Matt Feldman and Alex Monte, Guilford Journal of Chemistry, Volume 2, Pages 30-31 (2008).

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For our experiment, we used crushed frozen Mentos in 12 ounces of Diet Coke. By crushing and freezing the Mentos, it made the eruption last about three seconds longer. We used regular Mentos to compare results, and the eruption lasted about 5.5 seconds. With the frozen crushed Mentos, the eruption lasted about 8 seconds.

This picture was taken during our experiment while the eruption was taking place.

For our experiment, we studied the affect of the condition of the Mentos on how long the eruption lasted for. We put the Mentos in the freezer for 24 hours and then crushed them up into tiny pieces. We knew from research that freezing the Mentos would not affect the height, but we did not know how it would affect the time of the eruption. Also, we knew that crushing the Mentos had no affect of the height of the eruption. Therefore, we decided to test how these variables changed the affected the length of how long the eruption lasted. Our hypothesis was that crushed frozen Mentos will create a longer lasting eruption in twelve ounces of Diet Coke. This hypothesis was correct. The control in this experiment was testing how long it took for six regular Mentos to erupt. The Our experiment was very successful.

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Experimental Procedure:

1) 2) 3) 4) 5) 6) 7) 8)

Gather materials – including Mentos, geyser tube, Diet Coke, Put the Mentos in the freezer for 24 hours After freezing, crush the Mentos into tiny pieces Twist cap of 1st soda open and add the 6 crushed Mentos Record how long eruption lasts Repeat steps 2-5 for 3 more trials Repeat steps 4 and 5 with 6 regular Mentos Record all data in data table

The Affect of Frozen Crushed Mentos on How Long the Eruption Lasted

Type of Mentos

Trial 1

Trial 2 Trial 3

Frozen/Crushed

7.9

8.2

Regular Mentos

6.3

4.8

Trial 4

Avg.

8.3

8

8.1

4.8

6.5

5.6

(In seconds) The Affect of Frozen Crushed Mentos on How Long the Eruption Lasted

Time of Eruption (seconds)

Type of Mentos

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For our results, we concluded that when the Mentos are frozen and broken up into little pieces, the eruption lasts for a longer period of time. The eruption with the frozen crushed Mentos lasted longer than the eruption with the regular Mentos. These findings proved our hypothesis correct. In conclusion, our results were correct. We predicted that the smaller the Mentos were, the longer the eruption of the Mentos would last. We tested this experiment using regular sized Mentos, and then Mentos crushed into small pieces. For the eruption we used died coke in order to make the eruption height higher. Although, when crushed, our eruption did not go very high. As you can tell from our picture, it did not get much larger than a few inches above the coke bottle, yet it lasted for an average of about 3 seconds longer. This compared to the eruption of the full Mentos which would erupt meters about the coke bottle, but would last for an average of about 3 seconds less time. From this you can safely conclude the smaller the Mentos, the longer the eruption will last. Our data seems to be pretty exact because we got almost exactly the same results for each trial. The formula we came up with to show how Mentos size effects eruption time was for every time you cut the Mentos in half, the eruption will last for about a second longer. Meaning full Mentos would have about a 5 second eruption, Mentos cut in half would have a 6 second eruption, Mentos in fourths would have a 7 second eruption, and crushed Mentos would have an 8 second eruption. Of course, there was plenty of room for human error in the experiment seeing as we did not have a stop watch. Our counting was not very exact and there is a chance it was not consistent, meaning a great deal of room for errors to take place. However, these errors would be small ones and nothing that would take away from the overall results of the experiment. We believe we got the results that we did because when there are more Mentos pieces it will take a longer amount of time for all of them to erupt. This reaction is much the more Mentos you add the higher it will go, because there will be a larger reaction of something as you add more to it.

References 1. 2.

Rachel Cutler and Emma Smith Guilford Journal of Chemistry, Volume 1, Pages 6-8 (2008). Aaron Davis and Travis Dillon Guilford Journal of Chemistry, Volume 1, Pages 1214 (2008).

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Height of the Eruption When Increasing the Temperature of the Mentos By Jake Hill Stephanie Novelli and Amanda Bertschinger Summary For out experiment we wanted to test the effect of what the temperature had on the mentos. We froze the mentos and also kept them at room temperature. We then measured the height of the eruption and found out when increasing the temperature of the eruption goes higher. 2t(n+2)=h this formula helps to back up the results of what we found out. T representing the temperature of the surrounding area, N representing the temperature of the mentos and H representing the height of the eruption Amanda and Jake during the eruption

Introduction In general when adding mentos to coke it will cause the coke to violently erupt . Many people experiment with this because it is fun to do and fun to watch. This is a well known experiment which has many different causes. To read about many of the theories, read the Coffey Paper. 1 For our experiment, we studied the effect of the temperature of the mentos on the height of the eruption. Other students have conducted this experiment as well and we decided to use their results as a comparison. We saw that Rachel Cutler and Emma Smith had done this experiment and found that the frozen mentos create the biggest eruption .2 other types of experiments have been conducted such as the effect of the nozzle size. 3 others have done more simpler experiments such as the effect of the diet coke temperature.4 while doing this experiment we will be able to compare our results to previous studies done on this particular experiment. The reaction between soda and the mentos is usually a good one, although coke is preferred because it tends to react better, and although our experiment is not the same as other it still produced positive results. Experimental Procedure

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1. Obtain the materials needed to conduct the experiment. 2. Put one pack of the mentos in the freezer for one day, and leave the other one out to reach room temperature. 3. Begin to set up your experiment, by putting six mentos into the graduated cylinder and placing the meter sticks up against the wall to measure the height of the eruption. 4. Allow one person open and hold the soda while one person drops the mentos in. have to the other person stand back and write down the observations from the experiment. 5. Continue to collect data by doing two trials for each package of mentos. Record the results you get into your notebook. Materials 1. 4, 12 ounce bottles of diet coke 2. 2 packages of fruit mentos 3. A freezer 4. About 3 meter sticks Results We set out a goal to find out if the temperature of the mentos had any effect on how high the eruption of the soda went. To do our experiment we chose two temperatures to test; room temperature and frozen. We put one package of the mentos into the freezer for the day and left the other one out at room temperature untouched. We put 6 mentos in the graduated cylinder, then placed it on top of the diet coke bottle. Amanda and Jake conducted the experiment, while I stood back to write down the observations from the eruption. We used the room temperature mentos as a control and compared the results to the frozen mentos. Our experiment produced results that helped find and answer to the question that we were asking THE EFFECT OF THE TEMPERATURE OF THE MENTOS ON THE HEIGH OF THE ERUPTION

ROOM TEMPERATURE MENTOS

FROZEN MENTOS Trial 1

Trial 2

Average

Trial 1

Trial 2 Average

9.75 m

9.3 m

9.525 m

8m

7.5 m

7.75 m

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The Effect of the Temperature of the Mentos on the Height of the Eruption

25 20 15 10 height of eruption in meters

5 0 1

2

temperature of mentos in celsius

-5 -10 -15 -20

Conclusion By conducting this experiment we were able to find that the temperature of the mentos had an effect on the height of the eruption. The frozen package of mentos was left in the freezer of about -17 degrees Celsius for one day. The eruption was an average height of 9.525 meters. The other package was left at an average room temperature of about 20 degrees Celsius, and had an average height of 7.75 meters. The results showed us that the frozen mentos caused the greater eruption, and that the temperature of the mentos does play a role. although the results we got proved our initial thought right, there were a few errors made. They include not having enough time to find the average height for mentos that would have been heated otherwise. We also did not know the actual temperature of the freezer or room temperature, causing us to have to make an estimate of what e thought it was. Next time we will take an accurate temperature of the surroundings of the mentos. To make our results a little more accurate we should have done more trials, which would have allowed us with more data for out experiment. All in all we were able to prove our question right, the temperature of the mentos does have an effect on the height of the eruption. Although to make our results more accurate we would have done more trials to reassure the results we got. However we found that the temperature of the mentos has an effect on the eruption, and we are certain that whoever conducts this experiment will find the same results as us. References 1. Tonya Coffey, American Journal of Physics, volume 76, number 6, pages 551-557 (2008). 2. Rachel Cutler and Emma Smith, the Guilford Journal of Chemistry, volume 1, pages 6-12 (2007). 48


3. Aaron Davis and Travis Dillon, the Guilford Journal of Chemistry, volume 1, pages 17-18 (2007). 4. Justin Husted, the Guilford Journal of Chemistry, volume 1, pages 19-20 (2007).

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To Summarize our experiment, we discovered that diet coke produces the largest explosion of mentos eruptions, with sprite and club soda following behind. These results supported our hypothesis. Introduction

The purpose of our experiment was to test different types of sodas and their effect on a mentos eruption. The idea has become a phenomenon due to notable eruptions such as Steve Spangler's Mentos geyser from 2005. It originated with youtube videos, and as “Chemistry World explains,” the internet is a common place to begin documenting scientific findings. When mentos are placed in soda, most commonly used being diet coke, eruptions have been found to occur. Expansion and improvement on this idea has taken place ever since its discovery, often using the internet to do so. As Chemistry World explaains, “the internet is becoming flooded with free chemical information; from blogs to videos and databases.”

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Experimental Procedure

1. Gather Materials (4 12oz bottles of Club Soda, Sprite, and Diet Coke. Mentos, and tube.) 2. Place 4 Mentos in tube, secure it on the uncapped bottle of Diet coke. 3. Release the string and stand back to observe eruption. (Be sure to wear safety goggles.) 4. Repeat procedure for each bottle of soda. 5. Record heights of eruptions and any other observations. Experiment: Our experiment consisted of comparing three different types of sodas. We used 12 oz bottles of Diet Coke, Sprite, and Club Soda to test for any possible differences in the height of these eruptions when 4 mentos were placed in each bottle. Since Diet Coke is the most commonly used soda when testing this experiment, we predicted that it would cause the greatest eruption. Our data confirmed this prediction, however we did receive other interesting results having to do with the other soda. When the mentos were placed in the tubes and dropped in the uncapped soda, we recorded the data and found that all three soda types had some effect. We used the club soda as a form of a control, due to the pure carbonated water with no added sugars or chemicals. We found that the Club Soda produced the smallest reaction. Guilford Journal of Chemistry

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Results (continued) Types of Soda

Height (m)

Height (m)

Height (m)

Height (m)

Diet Coke

0.7

2.2

2.8

2.6

Sprite

0.6

0.9

0.8

0.7

Club Soda

0.2

0.2

0.3

0.2

Figure 2: The AveragevEffect of Types of soda on Mentos Eruptions.

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Conclusion Conclusion: Our hypothesis was correct. The Diet Coke soda made the mentos eruption highest out of all the sodas we used. Other sodas such as Sprite did not go as high because they didn’t have as much aspartame. The average of the Diet Coke eruption was 2.075 meters. Trial 1 of the Diet Coke eruptions had the most error because the geyser was not screwed on all the way. This made the bottle tip before being able to have a higher eruption. This is why trial 1 is only 0.7 meters and other trials are above 2 meters. If we were to repeat the experiment we would make sure that the geysers were always securely placed. The results for the Sprite eruptions were much lower than the Diet Coke eruptions. The average height of the eruption for Sprite sda was0.75 meters. The Club Soda eruption height average was 0.225 which is even lower than the Sprite eruptions. The Diet Coke eruptions were about 73% higher than the Sprite and about 94% higher than the Club Soda eruptions; the Sprite eruptions were about 71% higher than the Club Soda eruptions. Lauren Cutuli did an experiment on mentos eruption a couple years ago on the effect of diet sodas on the height of a mentos eruption. She discovered that Diet Coke had the second highest eruption. She concluded that the carbon dioxide bubbles would expand because of the gum arabic. In 2007, Ethan Shore and Zach Brown found that when testing different types of soda, found that Diet Coke had the second highest eruption. Their biggest eruption was Sprite Zero, which may be accurate but we did not test Sprite Zero. Dr. Coffey’s paper stated that sodas sweetened with aspartame had higher eruptions than sodas that are sweetened with corn syrup. Our experiment also showed this because the Diet Coke (containing aspartame) eruptions were higher than the Sprite (containing corn syrup) eruptions. The Club Soda had the lowest eruption because it is not made with any sweetener. In this experiment, there were many things that could have affected the height of the eruption. If we opened the soda bottle more than 30 seconds before putting the mentos in, the height would be affected. This happened to us with the Club Soda at first because we had to pour it into a 12 oz. bottle and then start the eruption. Also, if you do not screw on the geyser correctly, the eruption will not be as high.

References 1. http://stevespanglerscience.com/experiment/00000109. 2.http://www.rsc/chemistryworld/Issues/2007/December/SurfingWeb20.asp. 3. Read page 553 of Coffey's paper (see reference 2) for a detailed analysis of the effect of pH on the height of a mentos eruption. 4. Ethan Shore and Zach Brown, Guilford Journal of Chemistry 5. Lauren Cutuli, Guilford Journal of Chemistry

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B y E ri n S. a n d

As hle y B.

Summary The main focus of this experiment was the effect of the nozzle size of the height of the eruption. After conducting the experiment, our data showed that the medium sized cap was the optimum for height. The medium cap had an eruption height of 3.45 meters. The next best was the small cap. It had an eruption height of 4.325 meters. After that was the large cap, which had an eruption of 3.45 meters. Finally, the bottle with no cap had the lowest eruption height. It was far behind the others with an eruption height of only 1.05 meters. When this data is graphed, it creates a parabola. The formula for this data is y = - (x²-2) + 4.875. Y is the size of the nozzle and X is the height of the eruption.

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Ashley is about to pull the cord and release the mentos into the coke. 1

Introduction

In an earlier study done by Tonya Shea Coffey1 on the coke and mentos lab it was cited that the gum arabic and gelatin in the mentos, and caffeine, potassium benzoate, and the aspartame in Diet coke were the main contributors to the explosive reaction. It was hypothesized that the rough surface of the mentos can help break the strong polar attraction that water molecules have for each other by providing growth sites for the carbon dioxide. The pH of the diet coke prior to the reaction was 3.0, and the pH of the diet coke after the mint mentos reaction was also 3.0. The lack of change in pH supports the conclusion that mint 55


mentos Diet coke reaction is not acid based. The conclusion was also supported by the ingredients in the mentos which were also basic. Sugar, glucose syrup, hydrogenated coconut oil, gelatin, dextrin, natural flavor, corn starch, and gum arabic. The presence and absence of caffeine in the beverages contributes little to the experiment as well. Also it was found that the drinks sweetened with aspartame, such as Diet Coke are more explosive than the drinks sweetened with just sugar, due to a reduction in the work required for bubble formation when aspartame is added. Also if the growth of Carbon Dioxide bubbles on the sample takes place at the bottom of the bottle, then the bubbles will detach from the sample and rise to the top. The bubbles act as growth sites, where Carbon Dioxide still dissolved in the solution moves to the rising bubbles. If the bubbles travel farther through the liquid the reaction will be more explosive. There have been other attempts of the experiment concerning the same nozzle size done at Guilford High School. Similar results were found between the two experiments. Holly Aery and Adam Sierzputowski2, found out that the smaller nozzle sizes created higher explosions, which happened to be the same conclusion drawn in this experiment. The smaller the nozzle size the bigger the explosion, due to the more pressure it creates. An explosion is created due to internal pressure. Also according to Gabriella Necklas and Kiersten Wall 3 noticed that at a certain point the hole becomes too small for the geyser and it has the affect of creating a much shorter eruption. Which was also seen in this experiment.

2 Experimental Procedure

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1. Take a 500 mL bottle of diet coke and put a Geyser tube with 5 mint mentos in it and attach it the bottle of Coke. 2. Make sure the cap is screwed on tight. 3. Remove the red cap from the top of the Geyser tube. 4. Pull the red cord. 5. Record the height. And repeat steps 1-4 for 3 more trials. 6. Put the red cap back on the Geyser tube. 7. Repeat steps 1, 2, 4, and 5 for 4 trials. 8. Take the circular plastic cover from inside one of the cokes bottle caps. 9. Punch a medium size hole in the circular plastic cover 10. Place inside the red cap of the geyser tube, with the hole in the center. 11. Repeat steps 1,2,4 and 5 for 4 trials. 12. Then take a new plastic cover from inside one of the coke bottle caps. 13. Punch a small hole. 14. Place in red cap of the geyser tube. 15. Repeat steps 1,2,4and 5 for 4 trials.

Results After conducting this experiment, we found that the medium sized nozzle had the best height. The small nozzle was so small that the higher level of pressure did not matter. The coke just could not get out fast enough before the eruption was over. The coke with no cap had the lowest eruption height, which was expected. There was very little pressure because the opening was so big. The large cap (which was the standard red cover for the geyser tubes) erupted 2.4 meters higher. This is understandable because the large cap opening was about two times smaller than the opening of the bottle with no cap. Below is a table of all of data

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from the trials, along with the averages of each trial. For a graph of this data, refer to the back page.

3 Trial 1

Trial 2

Trial 3

Trial 4

Average

No Cap

1.1 m

1.0 m

1.1 m

1.0 m

1.05 m

Large Cap

3.8 m

3.0 m

3.6 m

3.4 m

3.45 m

Medium Cap

4.7 m

4.9m

5.0 m

4.9 m

4.875 m

Small Cap

4.0 m

4.2m

4.6 m

4.5 m

4.325 m

Conclusion

In conclusion, the medium sized cap had the highest eruption height. The expectation was that the small cap would have the highest eruption height, but the nozzle was just too small. Other experiments that are very similar to this one have been performed at Guilford High School. Holly Aery and Adam Sierzputowski² also found that a smaller nozzle size creates a higher explosion. Gabriella Necklas and Kierstin Wall³. From this data, it can be safely concluded that a smaller nozzle creates a higher eruption up to a certain point. The data from this experiment is fairly tight and repeatable. The second trial for the large cap is a bit of an outlier, but other than that, the data is good. The formula that represents this data is y = - (x²-2) + 4.875. This shows that the peak eruption is at 4.875 meters with the medium sized cap. You

can plug any other nozzle measurement in for Y, and it will tell you the height of the eruption for that specific size nozzle. For example, if you had a nozzle smaller than the smallest nozzle that was used in this experiment, than you would be able to find what the height of that eruption would be. Based on the results of this experiment, you could predict that eruption 58


would be smaller than 4.3 m, however, the formula would give you an exact answer. The reason that the small nozzle had a lower eruption height than the medium nozzle is that the opening was too small. Each eruption lasts for the same amount of time because the conditions are the same; the aspartame in the coke reacts with the mentos, which causes pressure that leads to an eruption. When the nozzle size was decreased, it created more pressure, which is why the eruption height rose between the bottle with no cap and the medium cap. However, once the small cap was put on the geyser tube, the pressure was higher, but there was just not enough pressure to push the coke out of the small opening any faster. A possible experiment for the future is testing different size nozzles to see which nozzle size allows for the highest eruption before the opening is too small.

4 References 1. Tonya Coffey, American Journal of Physics, Volume 76, number 6, pages 551-337 (2008). 2. Holly Aery and Adam Sierzputowski , Eruptions Caused by Mentos Increase in Height with Smaller Nozzle Sizes , Volume 1, number 5, pages 23-26(2008). [page 2 and 4 of this paper] 3. Gabriella Necklas and Kierstin Wall, Creating a “Misting Mentos Eruption,� number 8, pages 21-22(2008). [page 2 and 4 of this paper]

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Summary: In our experiment, the effects of four different diet sodas on the height of the mentos eruption were tested. The Specific diet sodas which we used were Diet Coke, Sprite Zero, Diet Pepsi, and Diet Canada Dry. Through testing these different types of diet sodas, the conclusions of Musterer and Ruotolo1 were both confirmed and disproven, with our Diet Pepsi trials confirming that it indeed does go higher than Diet Coke, but with our Sprite zero trials showing the complete opposite of their (and Shore/Brown’s ) 5 conclusions by coming in dead last in terms of height (with theirs coming in a close second to their Diet Pepsi. The final averages of eruption height came out to 6.25 meters for Diet Coke, 6.9 meters for Diet Pepsi, and 4.5m for Sprite Zero. (Diet canada dry is not included here because, in the trials, the second trial was a misfire, and corrupted the results.)

Diet Coke Trial 2/Failed Diet Canada Dry Trial

Introduction: The mentos eruption has been a popular experiment for just over 10 years now, ever since it was widely viewed on September 14, 1999 on the David Letterman Show2 , and tests on the effects of different brands of diet sodas seem to be fairly common, with at least two being performed at Guilford High School besides ours3. As of now, it seems that many, if not most, mentos eruption experiments are done purely using Diet Coke as the brand of carbonated liquid, with the current world record for mentos eruption height being held by a trial using Diet Coke4 , however the results of our trials show that, most probably, if such an experiment/ attempt at the world record were carried out with some other brand of Diet Soda, a much higher apex would be reached in the world of mentos eruptions.

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Experimental Procedure: 1. Obtain lab materials that are not provided by instructor/establishment (IE: 2xDiet Coke, Diet Pepsi, Diet Canada Dry, Sprite Zero, 8 packs Mentos-regular flavor) *All sodas are 2 liter bottles* DO NOT INGEST LAB MATERIALS. 2. Bring said materials to class with you, and obtain the provided materials from instructor/establishment (Eruption Tube, Safety Goggles) DO NOT REMOVE SAFETY GOGGLES WHILE CODUCTING TRAILS. 3. Set up your trials against the measuring stick which has been set up by your instructor with the Eruption tube screwed on VERY tight(to avoid misfires, like our Diet Canada Dry), with 10 mentos in each tube. 4. Wait for instructors queue, then pull string on eruption tube only if partner is holding the bottle to make sure it does not tip over . 5. Calmly move away from the testing site, fast enough to avoid getting hit by byproducts of the reaction, but slowly enough not to get hurt. 6. Watch the eruption, note the approximate apex height of the eruption, mark it down in your lab notebook (which you should have had since the 2 nd day of class) 7. Repeat steps 4-6 until your trials are done (two trials per brand) 8. For emphasis, DO NOT INGEST LAB MATERIALS, DO NOT REMOVE SAFETY GOGGLES WHILE CONDUCTING TRIALS, MAKE SURE THE ERUPTION TUBE IS SCREWED ON TIGHT. 9. Congratulations! You have successfully completed the experiment! Results: The results which were taken from this experiment and its trials were that the type of Diet Soda does indeed directly effect the height of the mentos eruption, and that, contrary to (probable) public belief, Diet Coke is not, in fact, the best contestant for mentos eruptions. The highest average eruption being the Diet Pepsi, with an average eruption height over two trials of 6.9m. The second highest average eruption came from the Diet Coke, which over the two trials had an average eruption height of 6.25m. The least (admissible) high eruption came from the Sprite Zero, which produced only a pitiful average height of 4.5m over the two trials. The trials for Diet Canada dry cannot be included in the results as a definite result, because during the second trial, one of the mentos got lodged within the eruption tube, causing the eruption to fail miserably (although, with a first trial at 7m, it was promising to be among the top of the list)

Chart and Table Included on The Next Page

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Results (continued) Use all the space you need. Include your table and chart- you can move things around as you like. Eruption Trials and Average Eruption Heights for Different Diet Sodas

Trial 1: 6m

6.8m

4m

7m

Trial 2: 6.5m

7m

5m

N/A

Avg: 6.25m

6.9m

4.5m

N/A

Eruption Trials And Average Eruption Heights (Graph)

This graphis just an example.

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Conclusion: After completing these trials during this experiment, it is clear and simple that the brand of diet soda most definitely effects the average height of the mentos eruption, a conclusion which is easily supported not only by our own data, but that of at least two others within the Guilford Journal of Chemistry, namely Musterer, Ruotolo, and Cutuli (all previously cited). In concurrence with Musterer and Ruotolo’s discovery, the results have shown that Diet Pepsi trumps Diet Coke through its eruption height, with an average height of 6.9 meters vs. Diet Cokes’ average of only 6.5 meters (a .4m difference on average). However, strangely, our trials on Sprite Zero have shown almost the complete opposite of their results, with an average height of just 4.5m, it came in dead last during our trials, with even the standard of Diet Coke beating it out by an average of 2m, whereas Musterer and Ruotolo’s results show Sprite Zero coming out on top of everything besides Diet Pepsi, with an average height twice that of their Diet coke trials. The results of the Diet Canada Dry trials showcased very clearly just how much error could have corrupted these results, however, with the fact that a single mentos getting stick derailed that entire section of the experiment. Some other errors which may have corrupted the results of the experiment (and in turn the conclusions) are, for one, the probable inconsistency of the mentos drops, which are more than likely each different not only due to the pure improbability of exact replicates, but also due to the fact that a new, clean, and dry Eruption Tube was not used for each trial, leading to preemptive reactions in the mentos. There is also always the factor of the time in which the bottle of diet soda is open, which (due to, again, the sheer improbability of exact replicates) differed each time almost without a doubt, leading to different losses of carbonation between each trial of every variable. For future experiments, we recommend trying more than 2 (preferably 4 or 5) trials for each variable, so as to lessen the amount of error caused by 1 single flaw during 1 single trial, as well as maybe trying other types of soda in addition to the current roster, so as to broaden the results of the experiment. So, in conclusion, even thought there were some conflicting results with other researchers of the same topic and a few possible errors, our results have shown that The type of Diet Soda does indeed effect the height of the mentos eruption.

References: 1. Angelise Musterer and Lindsay Ruotolo, , Guilford Journal of Chemistry, Volume 2, Pages 1213 (2008). 2. Guilford Journal of Chemistry, Volume 1 (2007), H. Brielmann, editor. Available online at http://chemistryadventure.com/Documents/guilford%20journal%20of%20chemistry%20volum e%201.pdf 3.Lauren Cutuli, Guilford Journal of Chemistry, Volume 2, Page 36-37 (2008). 4. Angelise Musterer and Lindsay Ruotolo, , Guilford Journal of Chemistry, Volume 2, Page 12 (2008). 5.Ethan Shore and Zack Brown, Guilford Journal of Chemistry, Volume 1, Pages 14-15 (2007).

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In the mentos experiment the one flavor of mentos that caused the highest eruption when dropped into diet coke soda was mint mentos. Mint mentos caused an average eruption of 4.1 meters, while strawberry had an average of 3.95 m, fruit had an average of 3.15m, and the gum had an average of .6 m. Each eruption four of each montos were used which in end would cause PENISa higher eruption then 1 minto.

Insert photo(s) here Insert photo(s) here

Insert caption here

In the Mentos experiment, the reaction of Mentos and soda was tested to see what flavor of Mentos would make the highest eruption in diet coke. In previous experiments it has been proved that the Mentos flavor of cinnamon generates the highest eruption 3. What is also known about this experiemnt is that the smaller the hole in the top of the bottle the larger the eruption, the more mMentos in the soda will cause a larger eruption, and the larger the bottle of soda will make a larger eruption. This experiment isn't testing any of those factors. If these factors did play a role in the experiment, it would be unknown to what caused the changes.

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Experimental Procedure 1. 2. 3. 4. 5. 6. 7. 8.

Gather 8,16oz bottles of diet coke soda and 2 packs of mint, strawberry, fruit, and mentos gum and one Gyzer tube. Put your safety glasses on. Take the cap off a bottle and place the Gyzer tube on the bottle. Put four of one kind of Mentos in the Gyzer tube. Pull the pin out of the tube and allow the Mentos to drop into the tube. Record the height of the eruption. Record the data Repeat steps 1-7 two times with each flavor of mentos.

The range of data that was found in the experiment was 4.2-.5 m. This range shows that there are many other factors that can change the height of a Mentos eruption. If only flavor effects the eruption this much, there may be endless factors that can change the eruption.

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Results (continued) Use all the space you need. Include your table and chart- you can move things around as you like. Figure 1: Insert Table Title Here

This table is just an example.

Figure 2: Insert Graph Title Here

This graphis just an example.

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The results of our Mentos experiment were very conclusive. It proved that the flavor of Mentos did have a large effect of the eruption height. Out of the four flavors of Mnetos we tested we concluded that Mint had the largest average eruption height of 4.1 m after two trials. Strawberry had the second highest eruption with an average of 3.9m. Third was fruit with 3.15m and gum had the smallest average eruption of only .60m previous research showed experiments similar to this one but with small eruptions. This may be due to the fact that the other experiments didn’t have/use Gyzer tube and they didn’t use four mentos per eruption which both have a large effect of the height of the eruption. Our data is very accurate and for the trials for each eruption are very close for the same mento type. With this data we can conclude that the Mint Mentos have the largest eruption height. If 2liters is equal to 67.628oz and divide that by the 16oz bottles used in this experiemnt then multiply that by the average height of our Mint Mento eruption would come out to 27.72m, which is only 2m away from the current world record

1. Kaitlyn Earles and Megan Graham, Guilford Journal of Chemistry, Volume 2, Pages 21-22 (2008). 2. Tonya Coffey, American Journal of Physics, Volume 76, number 6, pages 551-337 (2008). 3. Nick Hill and Kyle Gaboury, Guilford Journal of Chemistry, Volume 2, Page 38 (2008). 4. Read page 553 of Coffey's paper (see reference 2) for a detailed analysis of the effect of pH on the height of a mentos eruption. 5. Ryan Johnson and Will Graziano, Guilford Journal of Chemistry, Volume 2, Pages 9-11 (2008). 6. Alex Jagielski and Eric Hedberg, Guilford Journal of Chemistry, Volume 2, Page 38 (2008).

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Table of Contents Period 2 Jacob H, Ben B, Colton S The Effect of Different Sodas on the Height of a Soda and Mentos Eruption Craig A The Effect Various Mentos Has on Diet Coke Courtney O The Colder the Temperature of Coke the Higher a Mentos Eruption Anny Y Mint Mentos Erupt 16% Higher Than Strawberry Mentos and 55% Higher Than Green Apple Mentos with Diet Coke Anna K Increased Temperature of Diet Coke and Number of Mentos Increases the Height of Mentos Eruption Ambur D Two Bottles of Diet Coke Connected to Make One Eruption Will Heighten the Eruption Compared to a Single Eruption Period 3 Catherine D The weakening effects of Baking Soda and Sugar on the height of a Mentos in diet coke eruption Claire W and Lindsey U Mentos Soaked in Club Soda Prior to Trial Will Cause the Highest Eruption Shane G and Clara P How the Size of the Hole in the Nozzle Affects the Height of a Coke and Mentos Eruption Jenna P The height of the Mentos eruption depends on the outside coating Marguerite D and Alex P Diet Coke vs. Energy Drinks Period 4 Sara D and Alexa B Crushing Mentos will not make the eruption larger Andrew T and Mark L Mentos Car Eruption Michael G Diet Pepsi and Mentos: Elongated Eruptions

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Period 5 Ben E Drilling holes in the Mentos will increase eruption height Dan F and Samuel W The Effect of the Height of Introduction of the Mentos into the Diet Coke on the Severity of the Reaction

Evan H and Michel I Smaller Nozzle Size Creates Larger Spray during the Mentos Eruptions Grace I and Amanda M High Surface Area Increases a Coke Mentos Eruption Height Olivia S and Bronwyn R The Amount of Time between Opening a Bottle of Diet Coke and the Mentos Release Affects the Size of the Eruption Ashely Z and Katie N Fruit Mentos Caused the Largest Explosion as Opposed to Strawberry and Green Apple Mento Period 7 Jack F and Jamie W The Mixture of Mint and Fruit Mentos Produced the Largest Eruption Kate C., Anny Y., Annie X. Manipulating the Surface of Mentos: The Resulting Diet Coke and Mentos Explosion Height will Increase if the Increased Surface Roughness is Greater Than the Losses of Mass and Gum Arabic Juandiego C Manipulating the Surface of Mentos: The Resulting Diet Coke and Mentos Explosion Height will Increase if the Increased Surface Roughness is Greater Than the Losses of Mass and Gum Arabic Rebecca E and Klaire C Mentos, Baking Soda, and Vinegar‌.A Quench to an Eruption’s Thirst Zoe B and Nicole B Which Soda Provides the Best Mentos Eruption; Diet Coke, Sierra Mist, Mountain Dew Coke Zero, Diet Pepsi, Sprite, Club Soda

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The Effect of Different Sodas on the Height of a Soda and Mentos Eruption Jacob H, Ben B, Colton S

Summary For our experiment, we decided to test eight different types of soda to see how high their respective Mentos-induced eruptions would be, if any eruptions would even occur at all. The sodas that we used were Diet Pepsi, Seltzer, Grape Soda, Diet Coke, Sprite, Coca-Cola, Pepsi Max, and Coke Zero. We expected Diet Coke to produce the highest spray at 533.5 cm simply because this soda is the one most famously used in this experiment. However, Coke Zero surpassed the Diet Coke by 27.5 cm, achieving an astonishing height of 561 cm. In order from the highest spray to the lowest spray; Coke Zero (561 cm), Diet Coke (533.5 cm), Diet Pepsi (473 cm), Coca-Cola (434.5 cm), Sprite (363 cm), and Grape Soda (247.5 cm). Our two remaining drinks, the Seltzer and Pepsi Max, are unable to be compared to the other drinks because both tests involving these drinks failed. The Seltzer fell over mid-eruption and the Mentos became lodged in the geyser tube for the Pepsi Max. Introduction The Mentos Eruption Experiment has become a worldwide phenomenon ever since the first videos of this experiment started showing up on YouTube. Then, in 2006 the Discovery Channel show “Mythbusters” tackled the experiment themselves. Despite all of the publicity and attention this simple experiment has achieved, only one scientific paper has been written, reviewed, and published to the scientific community. In this paper, Tonya Coffey conducts the Diet Coke and Mentos experiment using a variety of sodas and potential reagents. At the end of her paper, Coffey concludes that potassium benzoate and aspartame are two main reagents that cause the eruption. She also concluded that the surface roughness of the reagents and the temperature of the sodas are major components in the reaction as well.1 Experimental Section Materials: 2 liter bottles of Diet Pepsi, Seltzer, Grape Soda, Diet Coke, Sprite, Coca-Cola, Pepsi Max, and Coke Zero at room temperature; 72 individual Mentos; a geyser tube; a damp rag for cleaning 1. Load 9 Mentos into the geyser tube and sure the pin and slider. Make sure the components won’t accidentally slip. 2. Unscrew the top of a soda bottle and quickly place the geyser tube into the bottle. Secure the tube to the bottle. 3. Place the bottle next to a wall or some device capable of measuring the height of the eruption. Angle the bottle approximately 80 degrees, pointing toward the wall. 4. Hold the bottle tightly to prevent it from falling over and pull the pin out of the geyser tube in a smooth, quick motion. Continue to hold the bottle throughout the eruption to prevent it from tipping. 5. Measure the height of the soda on the wall and record your data. 6. Use the damp rag to clean out the tube after the eruption to prevent the new Mentos from sticking to the inside of the tube. 7. Repeat steps 1 through 6 using each individual soda for as many trials as desired. Results Diet Grape Diet Sprite CocaCoke Pepsi Soda Coke Cola Zero Height of 473 cm 247.5 cm 533.5 cm 363 cm 434.5 cm 102 cm Eruption

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Height of Mentos Eruptions with Different Sodas 600 500 400 Height of Eruption 300 (cm) 200 100 0 Diet Pepsi

Grape Soda

Diet Coke

Sprite

Coca-Cola

Coke Zero

Types of Soda

Conclusion After conducting the experiment, we found that Coke Zero achieved the highest eruption. As for a scientific explanation for this result, we cannot provide one. The ingredients in Coke Zero are very similar to the ingredients in Diet Coke; they both contain aspartame and sodium benzoate, which Coffey found to be the major reagents in this reaction so as to why the Coke Zero achieved a higher eruption is unknown. It is also impossible to determine whether the data associated with any of these sodas is consistent because only one trial was conducted with each type of soda, so these results could have just been a random occurrence based on any number of factors. However, given the potentially flawed data as they are, general assumptions can be made. It appears that since the diet drinks (Coke Zero, Diet Coke, and Diet Pepsi) had the top three highest eruptions, something must be present in these three drinks that causes them to be particularly volatile when exposed to Mentos as opposed to the other drinks which still reacted to the mints, but not nearly as explosively. In addition to the potential for the data above to be flawed, it should also be noted that two other drinks, Seltzer and Pepsi Max were tested. However, these drinks were not included in the results because both tests malfunctioned and a reliable height measurement could not be obtained so it would be inappropriate to attempt to compare these two errors to the above data. A relevant follow-up experiment to ours could be conducted using the same sodas, however more trials for each soda should be performed in order to reveal if our data truly was flawed or semi-random; also additional trials would eliminate the need to exclude data because of failed trials such as ours. Endnotes Tonya Shea Coffey. “Diet Coke and Mentos: What is really behind this physical reaction?� 2008 Angelise Musterer and Lindsay Ruotolo. The Guilford Journal of Chemistry. Volume 2, pages 12-13 (2009). Another paper discussing a very similar experiment to ours in which they changed the types soda as well. 1

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The Effect Various Mentos Has on Diet Coke: Craig A

The mentos and coke experiment has become a wide known result. You drop a few mentos into diet coke and out comes a geyser of coke spraying out the top. But this experiment took the mentos and used different types of mentos to test the variable height of each type. In this experiment there was mint and fruit mentos present. The mint sprayed, at best, 54 bricks high (or 108 inches because one brick is two inches tall). The fruit sprayed, at best, 81 bricks high (or 162 inches high). So this proves that the fruit creates a more powerful geyser than the mint. Also in the experiment performed by the college student, Coffey, she had the fruit mentos producing an explosion of a greater distance than the mint mentos.1 They had stating that the fruit mentos burst 17.8 feet, while the mint mentos went 16.3 feet.2 In the experiment performed by Tonya Shea Coffey, she had mint mentos exploding a shorter distance than the fruit mentos.3 The mentos and diet coke experiment that was performed in this experiment produced results showing that different mentos do, in fact, produce different geyser heights. If different mentos produced different outcomes then different mentos must have different make-ups because they would produce the same outcome if they were the same in their make-up. With the background research in mind the mentos experiment was predicted to be only slight differences between the different mentos. Because the mentos have numerous tiny pores in the surface layer of the candy the coke, in reaction, releases carbon dioxide at a very rapid rate. This is what causes the geyser of soda to erupt.4 What also ignites the geyser is the gelatin and gum arabic inside the mentos. The gum arabic and the gelatin cause the foam to form in the soda.5 In our experiment the fruit mentos went higher than the mint mentos proving that there is a difference in the two mentos. That difference caused as much as a 50 inch difference in height, in the explosion. Materials: 2 pairs of safety goggles 4 bottles of 2 litter diet coke 2 rolls of mentos: o Fruit o Mint 2 geyser tubes (didn’t know what to call them) Safety:  Be sure to wear your safety goggle at all time when handling the products.  Be sure clear a good distance before during and after the explosion.  Be sure to make the dropping of the mentos to be fluid and quick/make sure they won’t get stuck and not fall in, but fall in later.  Be sure to not drink the soda or eat the mentos after the experiment. 1

Diet Coke and Mentos: What is really behind this physical reaction? By Tonya Shea Coffey ~ Coffey’s results show that the mint

mentos are less powerful than the fruit in the explosion. 2

Diet Coke and Mentos: What is really behind this physical reaction? By Tonya Shea Coffey ~ those numbers are from the packet

given to us by you. 3

Diet Coke and Mentos: What is really behind this physical reaction? By Tonya Shea Coffey ~ it was 2.5 feet of a difference.

4

Wikipedia: Mentos and Diet Coke ~ CO2 was released due to these pores. I found this fact on Wikipedia.

5

Wikipedia: Mentos and Diet Coke ~ I found that these were ingredients in the mentos on Wikipedia.

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Procedure: 1) Place safety goggles on your face. 2) Set your mentos into the tube, ready for the drop. 3) Place tube onto the diet coke. 4) Set up the coke so it is tilting just slightly towards the building, ready to move on to pull the string. 5) Pull the string and run a little away from the explosion to avoid the explosion. 6) Record observations. 7) Repeat the steps 2-5 for continuing trials and variables Heights: Trial 1: Trial 2: Fruit: 81 bricks 20 bricks: 202.5 inches 50 inches  There was a loose geyser tube and it exploded. Mint: 54 bricks 47 bricks 135 inches 117.5 inches

250

200

150 Trial 1 Trial 2

100

50

0 Fruit

Mint

This table shows that the experiment proved our hypothesis. The fact that there was such a difference in the heights shows that there is a different make-up between the two. A 202.5 inch height to a 135 inch difference is a significant difference when discussing the height. But when discussing the amounts lost, such as in Coffey’s experiment, there was 1440g lost from fruit mentos, and 1410g lost from the mint mentos.6 These results signify our successful completion of proving our hypothesis. The graphs and tables in Coffey’s lab prove and support our prediction as to how the mentos will affect the coke. They have small and 6

Diet Coke and Mentos: What is really behind this physical reaction? By Tonya Shea Coffey ~ That is only 30g which is a really small

amount.

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large differences in the mint and fruit conclusions.7 The experiment performed in this class has proof only with height. So the data is could have been expanded in so many ways, such as we could have had a third trial, or we could have had another kind of mentos. We could have also done left over in the can comparisons, eruption power comparisons, or types of soda. The geyser tube blew off so that changed our results and we got less reportable results. The table and graph are not as correct as they would have been had there not have been a mistake in the experiment.

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Diet Coke and Mentos: What is really behind this physical reaction? By Tonya Shea Coffey ~ Some data concludes that the fruit is

much more powerful, but in other cases the fruit is less of an outlier from the mint.

8


The Colder the Temperature of Coke the Higher a Mentos Eruption Courtney O

Our group tested the effect of temperature on the height of a Mentos eruption. We wanted to see if the coldness of the coke would make the eruption higher. We discovered that the colder the coke the higher the eruption was. When our coke was room temperature or 71 degrees Fahrenheit it erupted to an average of 30 bricks. When our coke was chilled at a temperature of 46 degrees Fahrenheit it erupted to an average of 33 bricks. When our sample was cooled down to 37 degrees Fahrenheit it erupted to an average of 34.5 bricks. This shows that cold soda does cause for a higher eruption but the difference between the chilled and cold soda is not very much. The percentage increase from room temperature to 46 degrees is 9%. Meanwhile the percentage increase from 46 degrees to 37 degrees is only 4%. This shows us that once the soda is cold it doesn’t have as much as an effect because the difference between the chilled and cold soda is not nearly as big a percentage between the room temperature and the chilled coke. The coke and Mentos experiment occurs when Mentos are dropped in a fresh bottle of coke and results in an eruption from the coke bottle. Depending on many different factors the height of the eruption can greatly vary. An experiment involving temperature was conducted by Cutler and Smith who showed that the height of the eruption could be dramatically increased by the freezing of the Mentos candies. This is similar to the experiment we conducted because it involves the coldness of the materials used. They also found similar results to ours showing that the coldness makes the eruption higher but after a certain point it doesn’t make as great of a difference. In the article written by Tonya Shea Coffey about what is really behind the physical reaction involved in a Mentos eruption he talks about how varying temperatures of soda cause the mass to vary which may show why an eruption is higher when the soda is colder. The lack of mass in the colder sodas could show the reason why we got the results we did, with the colder bottles of coke creating the highest eruption. When conducting a coke and Mentos experiment to see how temperature affects the height of the eruption you need to have a total of forty-five Mentos and nine bottles of soda to carry out the experiment accurately. You will also need a geyser tube and a way of measuring how high your eruption goes, such as a wall. The first thing you need to do is put six bottles of soda into the refrigerator waiting for three of these bottles to reach a temperature of 8 degrees Celsius and the remaining three to reach a temperature for 3 degrees Celsius. The three bottles you kept out of the refrigerator will be your control or room temperature samples and should be around 22 degrees Celsius. Once you have all your sodas at the proper temperature you put five Mentos into a geyser tube, line your soda up against your wall and drop the Mentos into a freshly opened bottle of soda. Repeat this for all nine bottles, so that you do each temperature three times. Find the average of this data and you will see if how cold the soda is affects the height of a Mentos eruption. Temperature ⁰C 22⁰C 8⁰C 3⁰C

Trial #1 32 bricks 33 bricks 32.5 bricks

Trial #2 28 bricks 35 bricks 36 bricks

Trial #3 31 bricks 31 bricks 35 bricks

Average 30 bricks 33 bricks 34.5 bricks

These results show that the colder the temperature of a bottle of coke the higher a Mentos eruption goes. This is significant because it shows that a temperature change has a certain effect on the eruption. A great follow up experiment that could be done would be how the eruption would be affected if you heated up the soda as opposed to cooling it down. If this experiment was conducted following the experiment where the soda was cooled down then you could see how temperature affects Mentos eruptions on a much bigger spectrum. This experiment was relatively reliable, and issue being that some of our sodas were on the wrong angle with the wall and one even fell down. For these reasons out experiment could not be called completely valid. Although when our sodas fell over and hit the wall the wrong way we repeated these bottles and got more valid results. The difference in these temperatures did not prove to be huge but definitely had somewhat of a difference. Since the change in height from room temperature to 8 degrees 9


Celsius was 9% this proves that there was some height involving the change in temperature. Meanwhile the change from 8 degrees Celsius and 3 degrees Celsius was a lot less drastic with a change in height of only 3%. For this reason it cannot definitely be proven that there is a huge difference between 8 degrees Celsius and 3 degrees Celsius. Some other interesting articles involving Mentos eruptions are about the discoveries made by Marsh and Moalli who kept and eruption going for 40 seconds and how Federici and LaChance found that cinnamon Mentos erupted 20% higher than any other flavor. 1. 2. 3. 4. 5.

Gather Materials- 45 Mentos, 9 bottles of coke, geyser tube, way of measuring Make 3 bottles of coke room temperature (22â °C) make 3 bottles 8â °C and make 3 bottles 3â °C. Put 5 Mentos in a geyser tube and align coke bottle with measuring tool. Drop Mentos into the bottle and record results Repeat this for each of the nine bottles

10


Mint Mentos Erupt 16% Higher Than Strawberry Mentos and 55% Higher Than Green Apple Mentos with Diet Coke Anny Y I. SUMMARY The purpose of this experiment was to investigate which flavor of mentos created the highest eruption with diet coke. There were three different flavors of mentos tested: mint, strawberry, and green apple. There were two trials performed for each mentos flavor. The height of the eruptions was measured by counting the amount of bricks the eruption’s spray reached on the side of a building. The results, in meters, were calculated by the formula: height of 1 brick=2.25 inches=0.05715 meters. The results for the mint mentos were 4.7 meters (82 bricks) and 4.0 meters (70 bricks) with an average of 4.35 meters. The results for the strawberry mentos were 3.4 meters (60 bricks) and 3.9 meters (68 bricks) with an average of 3.65 meters. The results for the green apple mentos were 1.9 meters (34 bricks) and 2.0 meters (35 bricks) with an average of 1.95 meters. These results show that the mint mentos erupted 16% higher than the strawberry mentos [use of formula: 1 – (3.65/4.35) = 0.1609 ] and that the mint mentos also erupted 55% higher than the green apple mentos [use of formula: 1 – (1.95/4.35) = 0.5517 ]. II. INTRODUCTION Diet coke-mentos eruptions are becoming a popular experiment in the world of science. The experiments include dropping about 5-10 mentos into usually a 2 L bottle of diet coke. The result is a large eruption of the diet coke spray, which is referred to as a geyseri. Interestingly enough, the mentos reaction is said to be a physical reaction and not a chemical one because when the mentos hit the soda, bubbles are formed over its surface, and the liquid is pushed out of the bottle in a violent eruptionii. What specifically causes the enormous eruption is still being investigated. Professor Coffey of Appalachian State University performed the mentos experiment, but first investigated the popular Mythbusters team’s experimental claims and eruptions which are posted all over the internetiii. Coffey’s report states that the Mythbusters correctly identified aspartame and potassium benzoate as the two key ingredients to set off the large eruptionsiv. The report also acknowledges different variable that may have an effect on the eruptions. It’s interesting to see just how many ways the experiments can be formed and what information can consequently be pulled from them. For example, not only diet coke has to be used in an eruption. Musterer and Ruotolo from The Guilford Journal of Chemistry conducted experiments and discovered than diet pepsi created an eruption 100% higher than that of the diet cokev. Another interesting experiment was that of Taylor and Schaffer, who discovered that a melted mentos will erupt at a slow rate that can sustain for hoursvi. This is very different from the other experiments because it measures not the height of an eruption, but how long it sustains for. Similarly, the experiment by Earles and Graham suggested that eruption power should be measured by volume of the eruptionvii. In their findings, the remaining soda volume for many soda sizes was constant which suggests that there is a fixed relationship between soda size and eruption volumeviii. Another experiment by Feldman and Monte, suggested that the more mentos added to the experiment, the higher the eruptionix. A final experiment similar to the one explored in this lab is that of Federici and LaChance, which suggested that cinnamon mentos eruptions are 20% higher than mint mentos eruptionsx. III. EXPERIMENTAL SECTION / PROCEDURE There were three levels of the independent variable in this experiment, which were mint mentos, strawberry mentos, and green apple mentos. There was no control in this experiment. The constants in this experiment were the amount of diet coke used in each eruption (2 L), the amount of mentos used in each eruption (10 mentos), and the distance from the diet coke bottle to the wall (1 ft). The dependent variable was the height of the eruption, measured in bricks and then converted into meters. Materials for the experiment included 6 2 L bottles of diet coke, 2 rolls of mint mentos, 2 rolls of strawberry mentos, 2 rolls of green apple mentos, an eruption chamber (dry). The procedure used to perform this experiment was: 11


Place 2 L diet coke bottle 1 foot from the brick wall and angle slightly toward the wall so that the spray will hit the wall but still reach maximum height. Open the eruption chamber tube and insert 10 mint mentos. Close the tube. Open the diet coke bottle and quickly screw the eruption chamber onto the top of the bottle until it is completely tight. Pull the string on the side of the chamber to release the mentos into the diet coke, and step back. Observe the eruption and count how many bricks tall the eruption reached. Repeat steps 1-5 with a dry chamber for a second trial. Repeat steps 1-6 with the strawberry mentos. Repeat steps 1-6 with the green apple mentos. Record all data and convert brick measurements into meters using formula: 1 brick=2.25 inches=0.05715 meters.

IV. RESULTS The results for the mint mentos were: trial #1- 4.7 meters (82 bricks); trial #2- 4.0 meters (70 bricks); an average of 4.35 meters. The results for the strawberry mentos were: trial #1- 3.4 meters (60 bricks); trial #2- 3.9 meters (68 bricks); an average of 3.65 meters. The results for the green apple mentos were: trial #1- 1.9 meters (34 bricks); trial #22.0 meters (35 bricks); an average of 1.95 meters.

Height (cm)

Average Height 600 500 400 300 200 100 0 Average

Type of Soda

12


5 4.5

Mint Mentos Erupt 16% Higher Than Strawberry and 55% Higher Than Green Apple

Height of Eruption (meters)

4 3.5 3 Trial 1

2.5

Trial 2

2

Average 1.5 1

0.5 0 Mint Mentos

Strawberry Mentos

Green Apple Mentos

Type of Mentos

V. CONCLUSION The results found in this experiment show that mint mentos had an average eruption 16% higher than strawberry mentos, and also an average eruption 55% higher than green apple mentos. The reason for these results could be due to different textures of the different flavored mentos, the different ingredients used for the different mentos, a different level of gum arabic in the mentos, or many other explanations. Ultimately, this experiment cannot provide a reason for the results. These results are not so significant that it would be assumable that mint mentos cause the highest diet coke-mentos eruptions. The validity of the experiment is not exemplary due to the amount of variables present in the experimental conditions. For example, there was no constant launching angle that the diet coke bottle was placed in. This would have affected height of the eruption sprayed on the bricks, because it would have angled the line of spray differently for each trial. A future recommendation to avoid this issue would be to set up a similar experiment but with a fixed launching angle of 40 degrees between the bottle and the ground near the wall. Another variable that could have poorly affected the results is the different time periods after opening the diet coke bottle. Between opening the bottle and letting the eruption go off there is a period of time where CO2 gas is leaking out of the soda. This would have affected the experiment by making the eruptions that had a longer time period weaker than those that had a shorter time period. A future recommendation to avoid this issue would be to set up a similar experiment but with a fixed amount of time of 15 seconds recorded and issued by a stopwatch between the opening of the soda bottle and the actual eruption.

i

Account of mentos-like eruptions dating back to the 1980s with an interview of Steve Spangler at http://www.rimmkaufman.com/blog/steve-spangler/21122007/ ii Steve Spangler article about what happens to the ingredients during a diet coke-mentos reaction at http://www.stevespanglerscience.com/experiment/original-mentos-diet-coke-geyser iii Mythbusters’s mentos experiments recorded in video at http://dsc.discovery.com/videos/mythbusters-diet-coke-andmentos.html iv Tonya Shea Coffey report on what is behind the mentos reaction and the validity of the Mythbusters’s claims at http://tnst.randolphcollege.edu/apply10/inst_mats/handouts/EnvSc/Coffey08_diet_coke_and_mentos.pdf v Angelise Musterer and Lindsay Rutolo, Guilford Journal of Chemistry, Volume 2, Pages 12-14 (2008). vi Sam Taylor and Will Schaffer, Guilford Journal of Chemistry, Volume 2, Page 38 (2008).

13


Kaitlyn Earles and Megan Graham, Guilford Journal of Chemistry, Volume 2, Pages 21-22 (2008). Dr. H. Brielmann, The Guilford Journal of Chemistry, Volume 1, pages 4-5 (2008). ix Matt Feldman and Alex Monte, The Guilford Journal of Chemistry, Volume 2, pages 29-31 (2008). x Allison Federici and Jess LaChance, The Guilford Journal of Chemistry, Volume 2, pages 15-16 (2008). vii

viii

14


Increased Temperature of Diet Coke and Number of Mentos Increases the Height of Mentos Eruption Anna K The hypothesis of this experiment was, If more mentos are used in an eruption when Diet Coke is at a higher temperature, then the eruption will be higher because there will be more matter being exerted from the bottle with a higher pressure. We completed six trials. These trials included increasing the temperature of the soda while at the same time increasing the number of mentos to see what difference, if any, would occur when these changes are made. 3 of the bottles had 4 mentos used, and 3 different bottles had 6 mentos used. One bottle of each was at a temperature of 298.15 K, one was 301.95 K, and one was 304.15K. The trial which had the results that most supported the hypothesis was the Diet Coke soda bottle which was at a temperature of 304.15 K and 6 mentos used, which had the highest eruption. The trial which least supported the hypothesis was the Diet Coke bottle at a temperature of 298.15 K and 4 mentos used, which had the shortest eruption. The eruption was measured by how high the soda sprayed against the wall. Each brick is equal to 5.5 cm, so the equation for figuring out the height of the eruption is: Number of bricks high × 5.5 = height of eruption. We counted the number of bricks and then used this formula to find the exact height in centimeters. Then we recorded the data and repeated this process for every other trial we had to complete. “The warm diet coke’s results sky-rocketed. Of the two warm test trials, both blast the coke into the air with a large amount of force, resulting in an average height more than double what the room temperature soda achieved.” ¹ This excerpt from the Guilford Journal of Chemistry supports the hypothesis by stating, like the hypothesis, that more force from the heightened temperature increased the height of the eruption. When four mentos were used with a soda temperature of 298.15 K, the eruption reached 440 cm. When four mentos were used with a soda temperature of 301.15 K, the eruption reached 473 cm. And when four mentos were used at 304.14 K, the eruption reached 473 cm as well. We then tested with the same temperatures, but with 6 mentos. When the soda was at a temperature of 298.15 K, the eruption reached 451cm. When the soda was at 301.15 K, the eruption reached 484 cm. And when the soda was at 304.15 K, the eruption reached 495 cm. There was an increase of height of eruption when 6 mentos were used rather than four. For example, at 298.15 K, there was an 11 cm increase. At 301.15 K, there was also an 11 cm increase. And at 304.15 K there was a 22 cm increase. “By the results of the data, it is easily safe to conclude that the warmer the diet coke temperature, the more height the eruption gained.” ² This also corresponds with the data obtained in this experiment, and it agrees with what was found within the data. And it could be concluded that the warmer the diet coke, the higher eruption occurred as well. “Our results clearly support the theory that using warmer Diet Coke will result in a higher Mentos eruption. Each time we raised the temperature of the soda, the result was a taller eruption, with our warmest bottle’s eruption reaching six meters! This can certainly be taken as proof that raising the temperature of Diet Coke affects the eruption size. However, a follow-up experiment where multiple trials are used would be a good idea to test the consistency of this fact” ³ Each time the temperature increased, the eruption increased regardless of how many mentos were used. But a significant increase was observed when 6 mentos were used rather than only 4. Although the data showed a definite conclusion, the data would be more precise and reliable if multiple trials were conducted. In the essay by Tonya Shea Coffey, it stated how Diet Coke heated to a temperature of 320.15 K lost 170 more grams of mass than Diet Coke chilled to a temperature of 279.15 K. 4 The loss of mass signifies the amount of matter exerted from the bottle, which means 15


that a greater eruption occurred when the Diet Coke was at a much higher temperature. “The temperature of the soda greatly affects how much force and height the geyser of soda fizz will shoot up to.” 5 The highest temperature used in the experiment also had much more force resulting in a higher eruption, and it shot up much higher. We placed each Diet Coke bottle into their own separate tub of water heated to specific temperatures (298.15 K, 301.15 K, and 304.15 K). Once at the correct temperatures, they were taken outside and set up against the wall and geyser tubes with either 4 or 6 mentos (depending on which trial) were tightly attached to the nozzle of the soda bottle. The eruptions were promptly set off after the bottles were open to ensure the most amount of pressure would be exerted. Then the height of the eruption was measured by counting the number of bricks high, and then using that along with the formula stated above to find the exact height of the eruption in centimeters. After reviewing the data from the experiment the conclusion is able to be made that the temperature of soda has an effect on the height of a Mentos eruption. As expected, the warmest soda had the highest eruption. [i]In the first 3 trials when we used only 4 Mentos for each different temperature, the heights of the explosions got higher for each trial; as the temperature was higher for each trial. The first trial when the soda was at 298 kelvin the eruption reached 440 cm. On the second trial when the temperature was 3 kelvin higher at 301 kelvin, the eruption reached 473 centimeters which is a great deal higher than the first trial. On the third trial however, when the soda temperature was 304 kelvin the height of the eruption stayed constant at 473 centimeters. However this may be due to error in the experiment, because in our second set of trials the third trial produced a higher eruption of 495 cm than at the second trial at 484 cm. This data is closely related to Justin Husted’s experiment from the Guilford Journal of Chemistry. The room temperature soda in his eruptions had expected results and was a relative increase from the cool soda. The warm diet cokes results sky-rocketed. [ii] When comparing results of this experiment to Justin Husted’s similar experiment, his data suggests the same overall conclusion. The final trial of his experiment was of the warmest soda which was heated in water measured at 308 degrees kelvin. The resulting reaction resulted in an eruption of 300 centimeters which was his highest.[iii] By the results of his experiment it was easy to declare that the temperature of soda does have an effect on Mento eruptions.[iv] Due to a kink in the data I collected, I cannot easily state the same with an equal amount of confidence but, my overall collection of data does suggest it.

[i] Husted, Justin. "Warm Soda Has a Dramatic Effect on the Height of a Mentos Eruption." Guilford Journal of Chemistry 1.1 (2008): 19-20. Print. [ii] Husted, Justin. "Warm Soda Has a Dramatic Effect on the Height of a Mentos Eruption." Guilford Journal of Chemistry 1.1 (2008): 19-20. Print. [iii] Husted, Justin. "Warm Soda Has a Dramatic Effect on the Height of a Mentos Eruption." Guilford Journal of Chemistry 1.1 (2008): 19-20. Print. [iv] Husted, Justin. "Warm Soda Has a Dramatic Effect on the Height of a Mentos Eruption." Guilford Journal of Chemistry 1.1 (2008): 19-20. Print.

16


Two Bottles of Diet Coke Connected to Make One Eruption Will Heighten the Eruption Compared to a Single Eruption Ambur D When two bottles of regular diet coke are connected to cause one eruption, the height of the eruption will be larger compared to a single eruption. When having nine mint mentos added to a single bottle of Diet Coke, the average eruption height will be 433.2cm. When dropping nine mint mentos at the same time to each Diet Coke bottle that is connected to cause one eruption, the average height will be 587.1cm. The Mentos Diet Coke eruption is a famous experiment with high school students. Mentos contain certain ingredients that cause this reaction with Diet Coke, or any soda for this matter. “The numerous small pores on the candy's surface catalyze the release of carbon dioxide (CO2) gas from the soda, resulting in the rapid expulsion of copious amounts of foam.”(Wikipedia) The outer coating the Mentos is important to the cause of an eruption. The small holes the Mentos contains allows the carbon dioxide to squeeze through, getting to the middle. “The potassium benzoate, aspartame, and CO2 gas contained in the Diet Coke, in combination with the gelatin and gum arabic ingredients of the Mentos, all contribute to formation of the foam”(Mythbusters). Gum arabic is a natural gum made of hardened sap taken from two kinds of the acacia tree and gelatin is solid substance, brought from the collagen inside animals' skin and bones. Potassium benzoate is an acid with a low-pH level, lower than 4.5 and aspartame is a noncarbohydrate sweetener used as a substitute for sugar. When all of these ingredients are mixed together with the carbon dioxide in Diet Coke, it causes the instant reaction called a geyser. Gather the supplies to complete this experiment. Attach two elbow shaped PBC plumbing pipes to one “T” shaped PBC plumbing pipe to create an upside-down football goal post or an upside-down digital “Y”. Then use Duct Tape to connect and seal the piping to the Mentos geyser tube provided by Steve Spangler (Educational Toys and Science Toys). Insert nine mint Mentos into each geyser tube carefully. Then slide in the stopper so the Mentos don’t fall out premature to the experiment. Unscrew both tops of the two liter Diet Coke Bottles and insert the geyser tubes in less than thirty seconds, otherwise the carbon dioxide will escape from the bottle. Once each geyser tube is inserted and screwed on the two liter bottles, pull each stopper out of each geyser tube at the exact same time to ensure accurate results. It would be wise to do it against a brick wall, that way counting the bricks first and multiplying that number by 5.7 centimeters is easier than just trying to count the height in centimeters. Create a data table with many trials to ensure accuracy and graph these results. The statement; When two bottles of regular Diet Coke are connected to cause one eruption, the height of the eruption will be larger compared to a single eruption, Proves to be true. Although, there is no mathematical way to explain the height difference between a combined eruption and a single eruption, the height was larger. By doubling the amount of carbon dioxide and other Diet Coke ingredients, while adding them to the doubled amount of ingredients in Mentos, essentially created a larger eruption. To ensure more accurate results it is always wise to do as many trials as possible and apply more duct tape to guarantee no leakage. Endnotes "Diet Coke and Mentos Eruption." Wikipedia, the Free Encyclopedia. Web. 12 Oct. 2011. <http://en.wikipedia.org/wiki/Diet_Coke_and_Mentos_eruption>.

17


"MythBusters: Diet Coke and Mentos Episode Summary - TV.com." TV.com - Free Full Episodes & Clips, Show Info and TV Listings Guide. Web. 12 Oct. 2011. <http://www.tv.com/shows/mythbusters/diet-coke-and-mentos-822481/>. "Geyser Tube." Science Projects Experiments, Educational Toys & Science Toys. Web. 12 Oct. 2011. <http://www.stevespanglerscience.com/product/geyser-tube>.

18


Period 3

The weakening effects of Baking Soda and Sugar on the height of a Mentos in diet coke eruption Catherine D The first time our group performed the experiment we tested how high five Mentos candies would erupt within a bottle of diet coke. We found that the average height at which it erupted was 131.5 cm. We came to this height by counting how many bricks the eruption went up, and measured the length of each brick in centimeters. Upon adding the baking soda and sugar to the diet coke, the eruption was much less impressive, since it hardly erupted higher than the top of the bottle, at about 11 centimeters for sugar and 8 centimeters for baking soda. The reason that it did not go that high was because by the time we got the Mentos into the coke, it had already begun to react. We can determine that the baking soda and sugar were both weakening factors to the eruption of the diet coke. Vinegar didn’t seem to alter the reaction as much, but it did make it go lower. The height of the eruption with vinegar was 76 centimeters. Introduction For our experiment we decided to verify Tonya Coffey’s results and test the effectiveness of adding baking soda to the diet coke. According to Coffey’s results, when she added baking soda to the soda it erupted to a height of 15.5 feet, or 472 centimeters. We also wanted to see how sugar added to the soda would affect the eruption. We came to the conclusion that diet coke does not react as well with sugar or baking soda, because our resulting heights for those experiments were much lower than the control. When adding baking soda and sugar to the diet coke at the same time, we saw that each time, the bottle would overflow without adding any Mentos to it. Experiment 1.

Gather all Materials needed for the experiment

2.

Using a tube that can release objects with the pull of a string, and place five mentos within the tube.

3. Open the diet coke, and as soon as possible place the tube over the coke and drop the mentos in, taking care to tilt the nozzle towards the wall so that the soda leaves a mark that can be measured 4.

Measure how high the soda shot upwards, and record the results; this will be your control

5.

Add 20 ml of vinegar to the soda and then put the nozzle on and repeat the process

6.

Add 20 ml of sugar to the soda and then put the nozzle on and repeat the process

7.

Add 20 ml of baking soda to the soda and then put the nozzle on and repeat the process

8.

Compile the data and graph it

19


Results We found through our experiments that baking soda and vinegar lessened the effects of the diet coke and mentos eruption. Initially when we tested the diet coke it went up 48 bricks, which is equal to 131.5 centimeters. That was the average of three tests we performed. We came to the conclusion that adding sugar would decrease the reaction because when we added it, the soda overflowed before the mentos even entered the soda, which made it go up only 11 centimeters. The addition of baking soda was equally as unsuccessful in increasing the reaction, because it reacted with the soda before the mentos went in and only caused it to erupt 8 centimeters. However when we added vinegar we did get a successful reaction, for the average of the three trials was 27.5 bricks which is 76 centimeters. Conclusion Since the results we found for these additions were harmful to the eruption, we can pretty safely determine that they do not make the coke more open to erupting. We did not think this would be the case, because according to Coffey, baking soda at least should have increased the reaction. According to NASA even, adding a sugary substance to diet coke should create a reaction with the coke, which shows why we did get a small reaction after adding the sugar. A possible reason we did not get strong results for when we just added the baking soda, vinegar, and sugar to the bottle is that there was too wide of a nozzle for the soda to escape from, which made it not go as high. Also the reaction might have started as soon as the sugar was put into the coke, which would have made the mentos less effective. An additional reason the baking soda might have caused the reaction to slow down, is because baking soda is a base which would take away the acidity of coke. Also the amounts of coke and variables used were different then the ones done in other experiments, which must have some impact on the results of the experiment. In the future, other people could place the soda bottle more carefully, or the pull the strings of the gyser more carfully so it doesn’t tip over , make sure that the bottle wasn’t shaken around before performing the experiment, and make sure that you’re using all the same flavor Mento’s for the same trial.

20


Mentos Soaked in Club Soda Prior to Trial Will Cause the Highest Eruption Claire W and Lindsey U

Summary According to the data, soaking Mentos will decrease eruption height from Mentos not soaked in anything, the control of the experiment. However, the highest eruption height came when the Mentos were soaked in club soda for one minute and left to dry for three. The average eruption height in bricks was 16.8 for club soda after three trials were conducted. There was about a 35% decrease from the control eruptions, which had an average eruption height of 26 bricks. Mentos soaked in saliva for a minute, left to dry for three minutes prior to the trial had average eruption height of 14 bricks and a 46% decrease from the control height. Mentos soaked in Diet coke for one minute and left to dry for three minutes had an average eruption height of 8.5 bricks and a 67% decrease from the control height. Mentos soaked in Pepsi for one minute and left to dry for three minutes had an average eruption of height of 6.17 bricks and a 76% decrease in eruption height from the control. Finally the smallest eruption was the result of Mentos soaked in a sugar solution of Splenda and water solution for one minute and left to soak for 3 minutes prior to trial had an average eruption height of 3 bricks and an 88% decrease in height from the control. Overall the additives that the Mentos were 21


soaked in lead to significant decreases in the heights of the eruptions. There was no significant pattern found in the data because it tested additive solutions and not quantitative changes, therefore a mathematical formula to describe these reactions would entail as follows: E=eruption height A= solutions that Mentos were soaked in and M=The Mento itself. So the simple equation is, M+A=E.

Introduction This unique experiment used to measure the height of an eruption soaked in a solution was created based on the results of Tonya Coffey, the professor of the Department of Physics and Astronomy at Appalachian State University. Coffey found that the significance of the ingredients caffeine, potassium benzoate, and aspartame in Diet Coke, and the gum Arabic and gelatin in Mentos which led to a higher eruptionx. In this experiment, many of the solutions used were of different sodas. Just like the findings of Shore and Brownx, Diet Coke did not have the highest eruption, Sprite Zero did. The findings of Musterer and Ruotolox also find that Diet Coke did not have the highest eruption, but Diet Pepsi did. These similar findings show that other solutions other than Diet Coke can have a higher eruption. In another experiment similar to this experiment, by Clark and Agamiex, their control had the highest eruption without any coating. This probably means that soaking a mentos in solutions probably won’t increase the eruption height. According to the findings of Hustedx, the cooler the soda, the smaller the eruption. The results of Husted were also supported by the results of Melillo and Guryanovx, who concluded that the higher the temperature the bottle is heated, the higher the eruption. This probably means keeping the diet coke at room temperature or higher will improve eruption 22


height. In this experiment, it was made sure that the soda was not cooled because of these findings. According to Moalli and Marshx, the ingredients in Mentos like gellan gum and gum Arabic cause a higher eruption because they dissolve, break the surface tension, and makes it so it is less work to expand and form new bubbles. to Moalli and Marshx, the ingredients in Mentos like gellan gum and gum Arabic cause a higher eruption because they dissolve, break the surface tension, and makes it so it is less work to expand and form new bubbles.

Experimental Section This experiment tested the effect of different solutions on Mentos when they were soaked and left to dry before an eruption. Club Soda, Human Saliva, Diet Coke, Pepsi, and a sugar and water solution was tested against a control. First a control was tested three times, where one Mento was dropped into an 8 ounce of diet coke through a geyser and made an eruption against the brick wall. Next, Mentos were dropped into cups filled with half a cup of each solution, and left to soak for approximately one minute. Then they were removed and were left to dry for approximately three minutes, leaving a coat of the specific solution on each Mento. After quickly opening the 8 ounce bottles one of the Mentos was then dropped into the geyser tube where it was then dropped into the Diet Coke to create and eruption which was measured against a brick wall. After three trials with each solution the data was recorded and the average was found, along with the percent decrease in eruption height from the control. Results

23


The Effect Soaking Mentos in Different Solutions has on Height Eruptions

30

Height in Bricks

25

29 25 2426 17.5 1816.8 16 15 14 14 12

20 15 10

Trial 1 11 8.5 8.5 6

5

Trial 2

9.5 7

Trial 3

6.17 3

2

5 1

3

0 Control

Club Soda

Saliva

Diet Coke

Pepsi

Splenda Solution

Solutions that Mentos Were Soaked

% Decrease from Control 100 80 60 40 20 0

67 35

76

88

46

0 % Decrease from Control

24

Average


Conclusion The results of this experiment show how different solutions or additives can deter a Mentos and Diet Coke eruption. It is important to consider the ingredients in each solution that the Mentos were soaked in, and how it directly relates to the results, the idea relates to the idea of Federici and LaChancex that mint Mentos have the highest eruption height because of their flavoring. Club Soda most likely made the highest eruption out of all substance coatings tested because it doesn’t contain sugar, most likely a major factor in why Coke and Mentos react together. This would explain why the Splenda solution had the lowest reaction, because the Mento would be coated with a sugar coating after coating. Therefore the higher the amount of sugar on a Mentos coating directly deters eruption height. Further experiments could entail picking out specific ingredients and soaking Mentos in them other than just picking certain solutions. This would clarify what additives to each substance cause the reaction rather than in this experiment where only the solutions themselves were tested. If conducted with sugary ingredients and non-sugary ingredients this experiment would prove the statement made in the previous paragraph. Experimental Procedure 1. Find a control height (no soaking in any solution) by dropping one Mentos in a 8 oz. Diet Coke bottle 2. Record the height of the eruption 3. Soak 1 Mento in Club Soda (Approximately one minute) 4. Wait for Mento to dry (Approximately three minutes) 5. Drop Mentos in 8 oz. bottle of Diet Coke from geyser 6. Measure height of Eruption (Number of Bricks) 7. Record in data table 8. Repeat process until completing 3 trials 9. Repeat steps 1-5 with saliva, diet coke, pepsi, and splenda solutions

25


How the Size of the Hole in the Nozzle Affects the Height of a Coke and Mentos Eruption Shane G and Clara P

Summary: The objective in this experiment was to see if the holes size in the nozzle would affect just how high the coke would reach when mixed with Mentos. We believed that as the hole got smaller then the coke would shoot higher because more pressure would be forcing the coke out. The pressure would build because the coke would not be able to escape as easily. However, we also believed that once the hole got to a certain point, of being too small, then the geyser would not reach as high because the stream would be too small to give a good push through the air, or because the intense pressure would simply cause the bottle to spray it out, rather than have it stream out, or the bottle would simply explode. (From the findings of previous experiments done and put on Wikipedia (http://en.wikipedia.org/wiki/Soda_and_candy_eruption)) Because of 26


this safety hazard, we were unable to create a hole that small. What we did find, using our four diameter measurements of 2.0 cm, 1.5 cm, 1.0 cm, and 0.5 cm, was that as the hole gets smaller the streams height would increase which proved our original hypothesis. Using two mint Mentos per trial, we found that the average height for the 2.0 cm hole was about 5.25 bricks high which is only 13 % of the largest average. The 0.5 cm hole shot an average of 39.75 bricks high. The 1.5 cm hole shot an average of 13.75 bricks, which is 35 % of the largest, while the 1 cm hole reached an average of 24.75 bricks which is about 62 % of the largest heights average. This proves our original hypothesis that a smaller hole will produce a larger height. Introduction: The Coke and Mentos reaction has been around since the 1980’s but was first widely introduced to the world on the David Letterman show in 1999. Since then there have been numerous videos and records of this type of eruption. In recent years more research has been done and even televised on shows like Time-Warp and Mythbusters. The Guilford Journal of Chemistry has included very conclusive experiments including those by Cutler and Smith who found that the temperature of the Mento can greatly increase the height. We believe that this could have some affect on the nucleation sights on the Mento which are believed to be the true cause of this reaction. We now set out to find our own way to increase the height of the eruption by building pressure in the form of less area for the soda to escape from.

Experimental Section: Materials: 1. Coca-Cola (all the same sized and shaped bottles, with the same amount of liquid.) 2. Drill or some way to cut an accurate and precise hole into the caps 3. A ruler 4. A lot of Mentos (use the same number and kind for each trial – we used two mint per trial) 5. Pencil and Paper for recording data 6. Way of measuring the height (we used the bricks of a wall that the Coca-Cola shot up against) 7. Duct Tape 8. Paper towels or a small cleaning rag Variables and Constants: Independent Variable: Size of the Hole in the Nozzle or Cap Dependent Variable: Height of the Eruption Constants: Since we did the majority of our tests within the same hour a few constants include the temperature of the coke and of the Mentos, the temperature outside, and the amount of wind stayed fairly 27


consistent throughout our time. Others include the type of Mento, the amount of Mentos per drop, the height of the drop, the angle the geyser tilted at, the bottle shape and size, and the amount of soda per bottle. We tried to keep the time between opening the cokes and dropping the Mentos as consistent as we could but there was no real accurate way of telling so I would like to change that next expieriment. Procedure: 1. Cut the holes into the caps, 0.5 cm, 1.0 cm, 1.5 cm, 2 cm diameters. (try to make the holes as clean cut as possible. Note that the geyser tubes original cap is about 1 cm wide and the tube without a cap is about 2 cm wide so the only ones really needed are the 1.5 and the 0.5 cm holes) 2. Wipe inside of geyser so Mentos do not stick with paper towels or a cleaning rag 3. Make sure the 0.5 cm cap is secured to the geyser 4. Flip over and put in two Mentos 5. Insert the key and flip back over 6. Open coke and secure geyser onto the top 7. Set down near a wall or measuring tape and release Mentos 8. Record height 9. Repeat two or three times (depending on supplies) 10. Repeat steps 2-9 for 1.0 cm, 1.5 cm, and 2 cm, diameter holes

Results: Hole Size (Diameter)

Hole Size (Area – cm2)

Trial 1 (Bricks)

Trial 2 (Bricks)

Trial 3 (Bricks)

Trial 4 (Bricks)

Averages (Bricks)

Percents

2 cm

3.142

5

6

5

5

5.25

13%

1.5 cm

1.767

14

13

13

15

13.75

35%

1 cm

0.785

25

24

26

24

24.75

62%

.5 cm

0.196

37

41

39

42

39.75

100%

These numbers show us that the smallest hole gives us the largest height for the stream of coke. The 2 cm diameter hole only reached an average of 5.25 bricks while the half a cm gave us an average of 39.75 28


bricks. The second largest hole had the second smallest height average of 13.75 cm while the second smallest hole had the second largest height average of 24.75. The three larger holes only reached a small percentage of the same height as the smallest hole showing that the smaller the hole is the higher the geyser will reach. (Graph in back) Conclusion: With the numbers previously recorded and discussed slightly we can conclude that as the hole got smaller, the coke would shoot higher because the high amount of pressure would be forcing the coke out in fast, tall upward motion. (Data from Holly Aery and Adam Sierzputowski, found in The Guilford Journal of Chemistry) As the hole size in the cap gets smaller the stream gets higher. This is very important because the original goal of all our experiments was to see how we can achieve the largest coke and Mentos eruption height. Many other tests were conducted by our fellow classmates trying to prove the same thing. They tested ideas such as types of Mentos, amount of Mentos, the height you drop the Mentos from, the temperature of the coke and of the Mentos, and even if there is a different type of drink that will make the eruption higher. We found that when the hole gets smaller the average height of the eruption will grow as well. A hole with a diameter of 2 cm only reached an average of 5.25 bricks off the ground. (We made the eruption next to a wall so we could measure the eruption based off the bricks as shown in the images below.) The second largest hole, 1.5 cm, reached an average height of 13.75 bricks. The third largest at 1 cm made it to an average of 24.75 bricks. Lastly, the smallest hole, with a diameter of only half a cm, reached an average height of 39.75 which is about 161% higher than the 1 cm diameter hole. The reason the smaller hole reached higher is because there is less of an opening for the soda to escape from meaning there will be more pressure forcing it out. However, we believe, due to this fact that if the hole is too small, then the pressure could theoretically become so intense that it would either shoot the cap off or cause the bottle to explode. (As explained in The Nozzle video on Youtube (http://www.youtube.com/watch?v=Q2tAGH2E_Bk) This is why we were unable to go to any size lower than half a cm. We would like to conduct a follow up experiment in a safer location where We can make the hole even smaller to see if it will just spray, form an actual stream, or explode. If this were to happen it would disprove our conclusion showing that there is an optimum sized hole for the maximum height. We would also like to do a follow up experiment on the Cutler and Smith experiment to see if it is instead the difference in temperature between the liquid and Mento.

29


References:

1. "Diet Coke and Mentos Eruption." Wikipedia, The Free Encyclopedia. 2011. October 8th, 2011. http://en.wikipedia.org/wiki/Soda_and_candy_eruption (Used in background and outside information on mentos eruption) 2. Holly Aery and Adam Sierzputowski. The Guilford Journal of Chemistry. Volume 2. Pages 23-26. (2011) (Helped to compare our findings to those of previous research, as well as helping to give data to our conclusion.) 3. "The Diet Coke Nozzle Test." Youtube. June 29th, 2007. Viewed in September-October 2011. (Gave an idea of what to expect, as well what what materials to buy, and helped in formation of hypothesis

30


The height of the Mentos eruption depends on the outside coating Jenna P

Summary: In our experiment, we discovered that the coating on the outside of the Mentos affects the eruption height. We put Mentos with coating and recorded the results however we then took Mentos that were sitting in water for a while and saw the eruption height. There was a drastic difference. With the coating we got results of 16, 21, and 25 bricks. Without the coating we had results of 3, 7 and 9 bricks. We therefore noticed that the coating of the Mentos affects the eruption height.

Introduction: During our experiment we took regular mint Mentos and compared the eruption height to Mentos without the coating on. Our hypothesis was, if we soak the coating off the Mentos then the eruption height would be affected drastically because the coating makes the soda fizz more. Our hypothesis was proven with the results we took. We didn’t tamper with the Mentos for the results of the Mentos with the coating, they were left normal. However, the Mentos with no coating were soaked in water to get all the coating off. To receive the results of the Mentos with coating we put 6 into the geyser and pulled the latch received varied results. We then took the Mentos soaked in water put six in the geyser and pulled the latch the same way we did with the coating and received varied results.

Experimental section: 1. Take 6 coated Mentos out of the package and transfer them into the soda geyser. 2. Take 6 Mentos and put them into a cup of water. 3. Then pull the latch to transport the Mentos in the geyser into the soda. 4. Observe what is going on and the height of the eruption. 5. When the eruption is finished count how high it went by counting the bricks. 6. Repeat steps 1-4 2 more times. 7. Take the Mentos from the water out and transfer then into the soda geyser. 8. Pull latch on geyser. 9. Observe eruption from Mentos without a coating. 10. Record results by counting the bricks to see the height of the eruption. 11. Then repeat 7-10 2 more times.

31


Results: Mentos: With outside coating Without outside coating

First trial 16 bricks 3 bricks

Second trial 21 bricks 9 bricks

Third trial 25 bricks 11 bricks

Our results were varied however all within a range. The Mentos with a coating had results between 15 and 25. Our first trial was the smallest eruption with a coating; it only went the height of 16 bricks. The second trial went the heights of 21 bricks, just a little higher than the first trial and our third and last trial received heights of 25 bricks and was the highest eruption height. Our results without an outside coating of the Mentos varied between 1 and 15 bricks. The first trial without a coating only went the height of 3 bricks and was the lowest eruption height we received. The second trial was 9 bricks and the third and last trials height was 11 bricks high and was the highest eruption height with no outside coating.

Conclusion: In the Mentos eruption experiment our results were clear that the outside coating affects the height of the eruption. We discovered the outside coating is the most important part to a Mentos and soda eruption. We received really high numbers with an outside coating compared to the Mentos without a coating. In other experiments we could find exactly what is causing the eruption and what is in the outside coating making the difference in the height.

32


Diet Coke VS. Energy Drinks Marguerite D and Alex P

Summary: In the lab, “Diet Coke vs. Energy Drinks”, we modified the classic Diet Coke and Mentos Eruption experiment by testing the Diet Coke’s eruption height in comparison to popular energy drinks, Rockstar and Monster. Diet Coke’s results suggested that Diet Coke was in fact better suited for the experiment. Diet Coke had an average eruption height of 13.5 bricks (40.5 inches). Monster came in second place with an average height of 8 bricks (24 inches), while Rockstar trailed behind with an average eruption height of 7.5 bricks (22.5 inches). These measurements resulted in a 57.4% difference between the Diet Coke and the energy drinks. These results did not support our original hypothesis that energy drinks would be better suited for the lab because of their assumed carbonation levels. Introduction: The Mentos Eruption Lab is a classic experiment where different carbonated beverages are examined to see which would produce the highest eruption height when combined with several Mentos. The Diet Coke and Mentos Lab is popular because “it inspires students to wonder and inquiry-driven labs/active-learning demonstrations on this reaction have been implemented.” [1] For the Mentos-Diet Coke reaction, the carbonic acid and carbon dioxide are not products of a chemical reaction but are already present the Diet Coke, whose equilibrium is disrupted by the Mentos. [2] The reaction to the Diet Coke occurs when several Mentos are dropped into the carbonated beverage. Though “numerous theories have been purported to explain the science behind the Mentos eruption”[3], we have come to believe that it’s due to the pressured carbonation being released by the disruption of the Mentos. Some say that “Depending on the number of Mentos dropped into the bottle, the spray height can vary between a few inches and tens of feet”[4]. However, we went in a different direction and made a slight change to the classic experiment by testing the eruption height of energy drinks, Monster and Rockstar. We were looking to prove, like the several unverified explanations of the experiment that have been offered to explain the experiment[5], that energy drinks carbonation would produce a higher eruption height than the original Diet Coke. Materials:  2 cans of Monster Energy Drink  2 cans of Rockstar Energy Drink  2 1L bottles of Diet Coke  3 rolls of Mentos  4 coke bottle nozzles  1 geyser tube  Duct tape 33


Procedure A: 1. 2. 3. 4. 5.

Take Coke bottle nozzle from a Coke bottle Attach geyser tube to the bottle nozzle Use a can opener to remove the top of the energy drinks can completely Use duct tape to securely fasten the Coke bottle nozzle to the top of the can Make sure to do this as fast as you can so you don’t lose too much carbonation

Procedure B: 1. 2. 3. 4. 5. 6.

Dress the Coke bottle up with the geyser tube so it is secure. Fill geyser tube with 4 Mentos. Pull geyser tube string to release the Mentos Back away from the eruption Repeat steps 1-4 and record results For the Monster and Rockstar portion, begin with Procedure A and follow steps 1-5 accordingly.

Data Table: Diet Coke

Monster

Rockstar

Trial 1

13 Bricks

9 Bricks

8 Bricks

Trial 2

14 Bricks

7 Bricks

7 Bricks

Average

13.5 Bricks

8 Bricks

7.5 Bricks

34


Conclusion: After two trials for each beverage, Diet Coke’s average height results of 13.5 bricks trampled the results of Rockstar’s 7.5 and Monster’s 8 bricks. This thoroughly disproved our hypothesis of the Energy Drinks having a higher success height than Diet Coke because of their carbonation levels. The failure of the Energy Drinks could be attributed to the fact that the cans release the majority of the carbonation. Something to attempt the prevention of this in the future would be to modify the top of the can so you can fit the Mentos in without completely removing the top. This might preserve the carbonation enough to get past only a few inches.

[1]

Diet Coke and Mentos: What is really behind this physical reaction?, Dr. Tonya Shea Coffey, page 1

[2]

Diet Coke and Mentos: What is really behind this physical reaction?, Dr. Tonya Shea Coffey, page 2

For an informative historical account of the Mentos Eruption, Steve Spangler’s website is recommended: http://www.stevespanglerscience.com/experiment/00000109 [3]

[4]

Diet Coke and Mentos: What is really behind this physical reaction?, Dr. Tonya Shea Coffey, page 1

[5]

Mass literature on the Mentos Eruption cites the website of Fred Senese

35


Period 4 Crushing Mentos will not make the eruption larger. Sara D and Alexa B

Summary: In our experiment, we crushed eight mint mentos and put four into two liter diet coke bottles. Then we put four non-crushed mentos into two liter diet coke bottles. As a result not crushing the mentos allows the eruption to be larger. Each brick had the height of 2.25 inches. Therefore when the mentos were crushed the first measurement was 78 inches. The second measurement was 72 inches. The height difference was six inches. Having the mentos not crushed during the third experiment had a height of 155 inches. The last experiment had a height of 157 inches. The difference between the heights was 2 inches. The difference between the crushed and non-crushed was 2%.

Introduction: It is said that the theory behind what makes the diet coke erupt is that there is an acid-base reaction because Coke is acidic.1 Some people tried to make an experiment to increase height. The world record is 30 feet and nobody has yet to make it. By trying to get more height people changed the soda type. As it turns out, the diet coke had the highest eruption. 2 What we did was to see if crushing the mentos would affect the height. We were incorrect, keeping the mentos how they are leads to a larger eruption.

Experimental Section: For this experiment we gathered all of our materials that include four two-litter diet coke bottles, sixteen mint mentos, and the device to launch the mentos. After, we set everything up, meaning placing the mentos into the tube then releasing the string. Once the coke erupted we calculated the results.

Crushed mentos

2m

1.8 m

Non crushed mentos

4m

3.9 m

Conclusion: After doing this experiment we found out that not crushing mentos allows the eruption to be higher. We know this because with the crushed mentos the average height was 75 inches. Having the mentos not crushed, the average height was 156 inches. We suggest that maybe after this experiment you can use more mentos (crushed and non-crushed) to increase the height. The reliability of our data is pretty high with some errors. All of our materials were constant and we used the same amount for everything. Though, some errors did occur. We opened the bottle a little early which released some carbon dioxide. Also the bottles could have been shaken. Procedure: 1. 2. 3. 4. 5. 6.

Gather materials: 4 two litter diet coke bottles, sixteen mentos, devices for eruption Set up materials Place 4 crushed mentos into the device Pull the string Count the number of bricks that the eruption hit Repeat steps 3-5 with crushed mentos 36


7. Repeat steps 3-5 without crushed mentos 2 times

References: 1

Reasoning for eruption- http://www.newscientist.com/article/dn14114-science-of-mentosdiet-coke-explosionsexplained.html

2

Angelise Musterer & Lindsay Ruotolo. Guilford Journal of Chemistry, Vol. 2, pages 1-2 (2009).

3. Guilford Journal of Chemistry, Vol. One, Page 5. (2008)

Www.rimmkaufman/rkgblog/2007/12/21/steve-spangler)

4.http://tnst.randolphcollege.edu/apply10/inst_mats/handouts/EnvSc/Coffey08_diet_coke_and_mentos.pdf

5. http://www.sciencebuddies.org/science-fair-projects/project_ideas/MatlSci_p023.shtml

37


Mentos Car Eruption Andrew T and Mark L

We discovered that when you put regular Pepsi on a car and put mentos in the tube it make the car move 3 feet from the curb. On the other hand when you put diet Pepsi with caffeine and put mentos in the tube the car only moves 2cm from the curb. After doing three trials of both sodas the number came out similar. The trick is to angle the soda up so the mentos can fall into the soda to cause the eruption. The car didn’t go for a long time it was more of a sprint it seemed like to me.

Procedure: Trial one Pepsi- 3 feet Trial one diet Pepsi- 2 cm Trial two Pepsi- 2.5 feet Trial two diet Pepsi- 1cm Trial three Pepsi- 1 foot Trial three diet Pepsi- didn’t move Something that Mark and I should have done was made it easier for the Mentos to fall into the soda because some of them would fall in but not all of them witch caused false information. 38


That picture above was of the last trial of the diet Pepsi. As you can see something went wrong and the soda started spraying all over the pavement. If I were to do this experiment again I would change a lot of things. First id get an r.c. car and the body off it and tape a two-liter bottle of coke and see what happens. I believe using more soda would make the car go longer and farther. I would suggest this experiment to a lot of people because it’s fun, keeps you entertained, and you can see how high you can get the soda to go. Also playing with mentos and soda is just fun.

39


Period Five

Drilling Holes in Mentos Will Increase Eruption Height Ben E

Summary The famous Diet Coke and Mentos eruption occurs when Mentos candy is dropped into a freshly opened bottle of Diet Coke, resulting in the famous eruption. Many factors are hypothesized to be behind the reaction, one of which is that the Mentos’s relatively rugged surface provides “nucleation sites” where CO2 bubbles form. Apart from only one accepted article by Professor Tonya Coffey, the study of Agamie and Clark which is printed in the Guilford Journal of Chemistry, and an episode of Mythbusters, there is currently little or no information on this subject. This experiment was conducted to see first-hand how surface area can affect eruption height, including the effect of using “donutMentos,” or Mentos with a hole drilled into the middle. Introduction The experiment was conducted to see how affecting the surface area of Mentos candy would affect the height of the eruption. Smoothed, roughed, normal donut, and smoothed donut Mentos were dropped into 2-liter bottles of Diet Coke. Due to problems with time, the trial involving roughed donut Mentos could not be executed. Experimental Procedure Materials that were used in the experiment include a six-roll pack of Mint Mentos candy, with 20 candies per roll, a sixpack of 2-liter Diet Coke, sandpaper for smoothing and roughing up the Mentos, a screwdriver for working holes into the Mentos, toothpicks for poking holes into the Mentos, and a Spangler’s Geyser Tube for releasing the Mentos and for directing the spray. The experiment was taken against a brick wall with an identifiable white silicone line around 54 bricks off the launch site. Each brick, plus the extra space taken by the mortar, measured 7.35 cm. The independent variable was the affect applied to the surface of the Mentos. The dependent variable was the height of the eruption. The control was un-tampered-with Mentos. Constants were the type of Mentos used (Mint), type of soda and quantity of soda used (2-liter Diet Coke), the temperature of the Mentos and the Diet Coke, and the launch site. Only one trial of each independent variable was done, due to lack of supplies. The procedure is as follows: 1. First, the Mentos has to be prepared according to the trial. Smoothed Mentos were rubbed on sandpaper for about 15 seconds on each side, while roughed Mentos were struck sharply across the sandpaper three times on each side. To make donut Mentos, a screwdriver was used to drill a small pit into each side of a Mentos, and then a toothpick was pushed through one of the pits, coming out the other side and forming a hole. Holes were formed in the Mentos before anything else was done to the surface. Ideally, the Mentos would be frozen at this point, but in this experiment, they were not. 2. The next step is to slip the Mentos into the Geyser Tube. Make sure the pin used to keep the Mentos from falling through prematurely is in place. Put eight of the current trial in the Geyser Tube. DO NOT open the bottle of Diet Coke yet. 3. Place the Diet Coke (unopened!) in the launch site. In this case, the bottle should be placed 15 cm away from the brick wall. Make sure the bottle is exactly upright; it cannot be tilting, or the launch height will be compromised. Make sure that the bottle is not shaken before or now. If it was shaken, it is recommended that the launch be put off at least 16 sec, for the soda to settle down. 4. Now is when the bottle is opened and the Geyser Tube goes on. Be aware, the moment the bottle is opened, the eruption begins to lose its potency because CO2 begins to escape from the open nozzle. Therefore, try to 40


minimize the time spent between the moment the bottle is opened and the launch; preferably about 10 sec. Make sure the Geyser Tube in on securely. 5. Once the Tube is on, stand back, count to three, pull the pin, and run. 6. After admiring the eruption, measure how high the eruption went. In this experiment, bricks were counted to gauge how high the spray flew. Then take off the Geyser Tube, toast to the successful launch, eat a Mentos, and repeat for another trial. Results The lowest of the eruption heights was achieved by the smooth Mentos, which reached a height of 46 bricks, or 352.8 cm. Next in the highest was the roughed Mentos, for despite tipping towards the wall, managed to reach up to 49 bricks, or 374.9 cm. Both the normal and the smoothed donut Mentos reached 59 bricks, or 433.7 cm, tying the two trials for the highest eruption height. The roughed donut Mentos trial was skipped, due to lack of time. The control trial, the normal Mentos, reached 51 bricks, or 389.6 cm. A graph for the data is available later in the report. Conclusion and Discussion Taking all of this data, it can be concluded that increasing the surface area of the Mentos will increase the height of the eruption, especially if a hole is poked through the middle of it. The smoothed, non-donut Mentos had the lowest eruption height of the trials at 352.8 cm, and the donut Mentos, both normal and smoothed, had the highest at 433.7 cm. It verifies the hypothesis that increasing the surface area of Mentos candies before dropping them into Diet Coke will increase the eruption height. It also correlates with the data from two other studies, Professor Coffey’s and Agamie and Clark’s. Coffey’s experiment was taken to test a whole slew of hypotheses about the Mentos eruption, one of which was how surface area affects the length of the eruption. They comfirmed that altering the roughness of the surface of the Mentos will increase the explosiveness of the reaction. Agamie and Clark’s study tested the effect of removing the coating on Mentos versus dipping them in dishwashing fluid on the height of the eruption. They found that they were both were surpassed by the control, which was normal Mentos. This is not surprising; removing the coating from the Mentos will essentially make the surface of the Mentos smoother, while dipping Mentos in dish soap will fill the nucleation sites present on the candies. Another study that can be pointed out is that of Marsh and Moalli, who tested the effect of applying different coatings on Mentos. However, since the dependant variable was the length in time of the reaction and not the height of the eruption, it has little significance to this study. Be aware that during the trial for roughed, non-donut Mentos, the bottle tipped, bringing the spray to bear against the brick wall. This caused the eruption height to go down, putting it below the control’s. Also, the trial for roughed, donut Mentos could not be executed, due to a lack of time. It would be worthwhile to come back and do a trial testing it. Overall, despite a couple of discrepancies, this study’s results matches those found by two others, and concludes that affecting the surface area of Mentos candy will increase the height of the spray.

41


The Graph: 450 430 410 390 370 350

330 310 290 270 250

Control

Smooth

Rough

Donut

Smooth Donut

Roughed Donut (N/A)

P.S. Due to some technical difficulties, it was not possible to label either axis. The x axis is the affect applied to the surface of the Mentos, while the y axis is the eruption height, in centimeters.

42


The Effect of the Height of Introduction of the Mentos into the Diet Coke on the Severity of the Reaction Dan F and Samuel W

Summary In our experiment, we attempted to adjust the entry level of the Mentos into a 1 liter Diet Coke bottle. Unfortunately, we were unable to get viable results because of faulty engineering. Introduction In an experiment that appeared in the paper “Diet Coke and Mentos, What Is Really Behind This Physical Reaction?�(End Notes, 4) a group undergraduates at Appalaichan State University, gum arabic was introduced at different heights as to see what effect it had on the eruption height. Releasing the gum arabic at a lower height on the bottle had a positive effect on the reaction, as shown by a higher eruption height (1). This is due to the carbon dioxide bubbles in the bottle having more exposure time to the reaction (2). This was also reflected by another experiment where crushed Mentos were compared with unmodified ones (3). The crushed Mentos were less effective because they took longer to reach the bottom and the majority of the reaction happened while the Mentos particles were falling. Experimental Section (Procedure) Materials: -1 unmodified 1l bottle (control) -1 bottle with a hole drilled at 10 cm from the bottom (1st mod) -1 bottle with a hole drilled 5 cm from the bottom (2nd mod) -1 modified syringe (5) -duct tape -wax paper -2 rubber bands -6 liters of Diet Coke -Ten rolls of Fruit Mentos Step 1: Insert Mentos into modified syringe, put wax paper Step 2: Pour soda into 1 liter bottle Step 3: push 4 Mentos into bottle Step 4: Measure height of the eruption Step 5: repeat steps 1 through 4 with the 2nd modified syringe, the one with the hole cut 5 cm from the bottom Results No valid data was collected as a result of faulty engineering. Conclusion In the experiment, it proved impossible to gather data as result of engineering flaws along with a few other mistakes. The seal between the syringe and the bottle failed to stay watertight, causing a loss of internal 43


pressure, and possibly caused a smaller eruption. A loss of carbonation also occurred when the Diet Coke was transferred from its original container to the testing bottle. A solution to these errors is to introduce the Mentos through a long tube placed through the top of the original bottle of Diet Coke, instead of pouring it into a modified one. Here is a materials list and procedure for this possible second experiment based upon this idea (There is also a diagram attached to the back): Materials: 1. PVC pipe, smaller in diameter than the neck of the bottle 2. Cut at lengths of 10 cm and 15 cm. 3. Copper wire 4. 3 2l bottle of Diet Coke 5. Duct tape (6) 6. Wax paper 7. Rubber bands Procedure: 1. For control, put Mentos in through the top, measure height 2. Put Mentos in 5 cm tube, seal at one end with rubber bands, wax paper 3. Put tube into top of the bottle, seal with duct tape 4. Push mentos through wax paper with copper wire 5. Record eruption height 6. Repeat with 10 cm tube End Notes Coffey, “Diet Coke and Mentos, What is really behind this physical reaction?” pg 555 Coffey, “Diet Coke and Mentos, What is really behind this Physical reation” pg 555 Coffey, “Diet Coke and Mentos, What is really behind this Physical reation” Pg 556 Coffey’s paper was an investigation into the now popular Diet Coke and Mentos experiment. She and a group of undergraduates tested different aspects of the reaction, like changing the surface area using different ingredients, and introducing the Mentos in different ways. 5. The modified syringe we used had the top sawed off so the Mentos could be pushed in using the plunger. 6. An alternative to the duct tape, and probably a more effective mode of sealing the tube would be to use something like the screw top on the Geyser Tube. 1. 2. 3. 4.

44


Smaller Nozzle Size Creates Larger Spray during the Eruptions

Mentos

Evan H. and Michel I.

Summary: For our experiment, we covered a soda bottle with a geyser tube with three different covers to see the effects on the eruption caused by combining Mentos and diet coke. The covers that we used were a geyser tube with 1) a cap (1.5 cm opening), 2) a coke bottle cap with a hole (1 cm opening) and 3) a garden hose nozzle (0.5 cm opening). In so doing, we were able to see if a smaller nozzle size created a larger spray during a Mentos and diet coke eruption. The geyser tube with the coke bottle cap with a 1 cm hole created the highest eruption measurement of 396 and 401 cm. The geyser tube with the 1.5 cm hole in the cap created an eruption reaching 340 and 314 cm. The geyser tube with 0.5 cm hole garden hose nozzle created the lowest eruption height of 152 and 290 cm. Introduction: A liquid eruption can be created by increasing the pressure within a fluid held in a closed space. During a Mentos and Diet Coke experiment, Mentos mint tablets are introduced into a bottle of Diet Coke or Pepsi. The resulting reaction is a stream of soda, which is guided through the neck of the bottle. The reaction within the bottle is due to a rapid release of carbon dioxide bubbles. In its simplest form, the Mentos and diet coke experiment usually involves dropping Mentos mints into diet coke, resulting in a foamy eruption, which can often be several meters in height.š When the two elements combine, they result in a massive increase of carbon dioxide pressure released from the Diet Coke. It expands the liquid and forces it out the top of the bottle.² In the past there have been many theories to explain the science behind the Mentos Eruption. The first widely viewed Mentos eruption occurred on the David Letterman show on September 14, 1999 3. In terms of scientific research this field is still in its still a fairly unproven area. There have been numerous videos and TV shows documenting eruptions. One of the most well-known documented experiments is on the set of the TV program Mythbusteres 4.

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Experiment: In this experiment, three nozzles of different size (0.5cm, 1 cm and 1.5 cm) were individually put onto a release mechanism called a geyser tube. The geyser tube was then loaded with a Mentos tablet, held in place by a pin, so that the Mentos tablet was held inside the geyser tube. The loaded geyser tube was then placed over a 1 liter bottle of Diet Coke. The pin was pulled, allowing the Mentos tablet to enter the bottle of Diet Coke. The emitted stream of liquid was measured for height. Each nozzle setup was sampled twice.

Graph 1

450 400 350

Height of 300 eruption 250 stream(cm) 200

Trial 1 Trial 2

150 100 50 0 Bottle cap w/ hole (1 cm)

Geyser Tube w/ cap (1.5 Nozzle cm) Type

Garden Hose Nozzle (0.5 cm)

Results:

Table 1

Nozzle

Height of stream (cm)

Bottle cap w/ hole Geyser Tube w/ cap Garden Hose Nozzle

Trial 1

Trial 2

396 340 152

401 314 290

Conclusion: During the Diet Coke and Mentos experiment, the different sized nozzles over the geyser tube proved to be the difference in average eruption height. As seen in the Graph 1 and Table 1, the smaller the nozzle width the higher the mentos eruption. This is up until the hole gets too small, at around 0.5 cm, as shown with the garden hose nozzle. These results most likely occurred due to the increase in eruption pressure from the soda. For example, if one was to spray an open hose, it generally does not go very far. But, when you use a thumb to close off part of the hose exit, the water accelerates and goes farther. Some errors that could have been present during the experiment were 1) a variable in the time it took to secure the geyser 46


tube on each coke bottle which allowed CO2 to release from the Diet Coke and 2) an imperfect nozzle fit, which allowed pressure to leak around the nozzle. Also, the nozzles could have been angled, changing the height of the eruption. One follow-up experiment could be to increase the number of width gradations (1, 0.85, 0.75, 0.65 and 0.5), in order to determine the point at which the nozzle width hinders the height of the eruption. The significance of these results shows that a smaller the nozzle width will cause a higher eruption when conducting a Diet Coke and Mentos eruption. Experiment Procedure: Gather materials: 10 one liter bottle of Diet Coke, 2 packages of mint Mentos, and a piece of ply wood (1 foot by 6 inches), one Mentos experiment plastic geyser tube with cap, measuring tape, water balloon hose nozzle, bottle cap with 1 cm opening Step 1: Extend the measuring tape vertically up the wall about 20 ft. Step 2: Put 2 Mentos mints in the geyser tube with the pin securely in place with the original cap of top of the tube. Step 3: Set up your experiment area by laying the piece of plywood down, next to a wall, near the measuring tape. Step 4: Place the closed bottle of diet coke on the ply wood, angled slightly at the wall. Step 5: Quickly unscrew the cap of the diet coke bottle, place the geyser tube in the top of the bottle and screw it onto the bottle. Step 6: Pull the cord attached to the pine, making sure it doesn’t tip the bottle, and run to a safe distance. Step 7: Record the eruption height on the wall, in comparison with the measuring tape Step 8: Repeat steps 2-7 once more. Step 9: Place the garden hose nozzle on top of the geyser tube and duct tape it on to ensure there is no pressure leakage Step 10: Repeat steps 2-8 with the garden hose nozzle Step 11: Place one of the coke bottle caps on a flat working environment Step 12: Hammer the nail into the center of the cap Step 13: Replace the top of the geyser tube with the bottle cap Step 14: Repeat steps 2-8 with the improved geyser tube End Notes: 1. Dr. H. Brielmann, The Guilford Journal of Chemistry. Volume 1, Page 1 (2007) 2. Tonya Shea Coffey, Diet coke and Mentos what’s early behind the physical reaction. Page 551 (2008) 3. The original Letterman Show Mentos Eruption may be viewed on the internet 4.

(http://www.chem.uic.edu/marek/letterman0/video/mentos.htm.) The original mythbusters investigation of the mentos eruption may be found online at (http://dsc.discovery.com/videos/mythbusters-diet-coke-and-mentos.html).

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High Surface Area increases a Coke Mentos Eruption Height Grace I and Amanda M

Summary: An increase in the surface area of a Mentos also increases the eruption height. According to the paper "Diet Coke and Mentos: What is really behind this physical reaction?" Tonya Coffey also agrees with this statement.1(551) When conducting the experiment, the data shows that when a Mentos was scratched on both of its sides the height of the coke and Mentos eruption increased compared to when the Mentos was left smooth or only scratched on one side. In fact, the Mentos eruption increased by 30% when the Mentos was scratched on both sides. However, our data did show that when the Mentos was scratched on only one side the eruption height was less, by one-third of an inch, then the eruption height of a smooth Mentos. This decrease may just be experimental error and if conducting the experiment again should be retested. Introduction: Coke and Mentos is a famous experiment where Mentos are dropped into a bottle of coke and the soda erupts. In our studies we tested to see how surface area effects the explosion. Other studies have been conducted and have also hypothesized that a rough surface of the Mentos can help break the strong polar attraction that water molecules have for each other by providing growth sites for the carbon dioxide.2(551) Our data conveyed the results that our hypothesis as well as the hypothesis in Tonya Coffey's paper are correct.3 (557) Increased surface roughness implies a higher surface area to volume ratio, meaning that more growth sites should be present on per unit volume.4 (556) In fact, surface roughness may be one of the most important causes of the eruption. 5 (556) Mentos with a lower surface area result in a smaller eruption. 6 (556) Tonya Coffey also tested different items other than Mentos to drop into the coke.7 (553) She found that Wint-O-Green Lifesavers, which had root-mean-square roughness of 2630, created the highest eruption compared to mint Mentos, fruit Mentos, and rock salt.8 (553) The Wint-o-Green Lifesavers have a rms roughness that is more than a factor of 10 larger than the rms roughness of the rock salt.9 (556) The Lifesaver reaction had the largest eruption spray.10 (556) Experimental: In this experiment, Mentos with different surface areas are dropped into 12 oz. bottles of coke. To do this experiment, you have to gather all materials: 9 bottles of coke, 9 Mentos, a geyser tube, a measuring tape, and a paper clip. Then, 3 of the Mentos have to be scratched with the paper clip, on one side and 3 of the Mentos have to be scratched on both sides. The remaining 3 Mentos will be left smooth on both sides. Put one of the smooth Mentos into the geyser tube and drop the Mento into coke bottle. Measure the height and record the data. Then do the same steps with the one side scratched Mentos, and the both side-scratched Mentos. Do 2 more trials for each surface area and record the data.

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Mentos surface area Trial 1 Trial 2 Trial 3

Smooth

One side scratched 51 51 64

Trial 3 height 56 46 67

Average 41 49 48 48 79 70

Results: In this experiment, we tested how the surface area of the Mentos would react differently to coke. There wasn’t a significant difference between one side scratched eruption height and the smooth Mentos eruption height. The one side scratched Mentos average eruption height was 48 cm and the average eruption height was 49 cm. Although, there was a significant difference between the both sides scratched Mentos and the other two Mentos. The average eruption height of the both sides scratched Mentos was 70 cm or a 21 cm difference in height. The results were not always consistent. For example, the second trial for the smooth Mentos was 56 cm while the third trial was 41 cm. Some of the results were consistent, though. For example, the first trial height of the one side scratched was 51 cm, the second trial height was 46 cm and the third trial height was 48 cm, which were all relatively close in height. The two sides scratched Mentos were not that consistent either because the first trial eruption height was 64 cm or the second trial height was 79 cm. Conclusion: It was hypothesized that different amounts of surface area on Mentos would change the eruption height when the Mentos were dropped into coke. The hypothesis was proven correct, but only slightly. In the results section 49


it said that there was not a significant difference between the smooth Mentos, and the one side scratched Mentos eruption heights but there was a big jump in eruption height between those two and the both sides scratched Mentos. A scratched surface area on a Mentos makes the eruption height taller because the growth sites of the bubbles are already exposed. The reason for the smooth Mentos and the one side scratched Mentos having similar eruption heights was that the time it took for the coating to come off one the smooth Mentos was not that different from the amount of time the coating took to come off of the one side scratched Mentos. For the two sides scratched Mentos, though, the eruption was immediate because it barely had any coating on its surface which meant that there would be more carbon left in the coke to make a larger eruption. The surface area has to be completely scratched to make a significant difference in eruption height. It also stated in the results section that the data of the smooth and both sides scratched Mentos was inconsistent while the data for the one side scratched Mentos was consistent. It was predicted that the both sides scratched and the one-side scratched Mentos would have the inconsistent results because each Mento wouldn’t have been scratched the exact same amount. It was also predicted that the smooth Mentos would have very consistent data because they have the exact same amount of surface area. I believe that the results turned out the way they did due to errors in the experiment. One error was that some bottles of coke make have been shaken a little bit due to the process of taking the cap off, and putting the geyser tube on which leads to the other error. The other error that could have occurred was the amount of time in between taking the cap off of the bottle and dropping the Mentos into the coke bottle. The more time it took to get the mento into the bottle of coke, the more carbon was released from the bottle which meant that the reaction would be smaller. Changes I would make to this experiment if it were retested would be the amount of trials because some trials more have had error and that would affect the data. More trials would give a more precise and accurate reading of the eruption height of Mentos with different surface areas. In conclusion, high surface area of Mentos increases a Mentos eruption height. Endnotes: 1. Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 551 (2007) 2. Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 551 (2007) 3. Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 557 (2007) 4. Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 556 (2007) 5. Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 556 (2007) 6. Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 556 (2007) 7. Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 553 (2007) 8. Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 553 (2007) 9. Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 556 (2007) 10. Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 556 (2007)

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The Amount of Time between Opening a Bottle of Diet Coke and the Mentos Release Affects the Size of the Eruption Olivia S and Bronwyn R Summary This experiment tested the effect of the amount of time between opening a bottle of Diet Coke and the release of Mentos into the coke on the height of a Diet Coke-Menots eruption. It was hypothesized that if the amount of time between the opening of the Diet Coke and the Mentos release is increased, then the eruption will be smaller because there will be less carbon dioxide. To test this hypothesis, there where three different amounts of time used, thirty seconds, one minute and five minutes. There were two trials for each time tested. The average height of the eruption after thirty seconds was 60. 5 bricks (332.75 cm), after one minute was 52 bricks (286 cm), and after 5 minutes was 47 bricks (258.5 cm). Introduction This experiment came into the public eye after it was used on the David Letterman show in 1999 and after it was a subject on the show Mythbusters in 2006.x Since then, the experiment has become a popular science experiment in elementary to college level classrooms.x In its simplest form, the Diet Coke-Mentos explosion experiment is dropping fresh Mentos into a newly opened bottle of Diet Coke, creating an eruption that can range from a couple of inches to the world record of 29.2 feetx, depending on the number of Mentos placed in the soda.x The basic ingredients that cause this reaction are gum arabic and gelatin in the Mentos as well as the caffeine, potassium benzoate, and aspartame in the Diet Coke.x The carbonation in the soda also has an effect on the height of the eruption.x In this experiment, Diet Coke is used because it contains aspartame and caffeine, two crucial ingredients to the success of the explosion.x Mint Mentos were also used because they do not have an outer coating, like many other flavors of Mentos. This allows more CO2 bubbles to form on the candy, resulting in a bigger reaction.x

Materials Six bottles of Diet Coke Twelve mint Mentos One geyser tube One stopwatch A pair of safety goggles Tape measure (optional) Procedure 1. Place two Mentos inside the geyser tube 2. Put on safety goggles 3. Set coke bottle on the ground, next to a wall, and at an angle so that when an eruption occurs, the coke can hit the wall, making it easier to measure the height of the eruption. 4. Simultaneously open the coke bottle and start the stop watch 5. Screw the geyser tube onto the opening of the coke bottle- DO NOT release the Mentos 6. When the stopwatch reaches thirty seconds, release the Mentos and stand back from the coke bottle. 7. After the eruption has stopped measure up to the highest point of the eruption (which should be where the coke hit the wall) by counting the number of bricks it reached to, or using a tape measure. 8. Record the height of the eruption. Repeat this trial. 9. Repeat steps 1-8 replacing thirty seconds with one minute, then five minutes. 51


Results Our experiment tested the explosion height of the Diet Coke after different lengths of time from the opening of the bottle. On the whole, the longer the bottle had been kept open, the shorter the height of the explosion. For example, when the Mentos were dropped in 30 seconds after opening the bottle, the average eruption height was 60.5 bricks (332.75 cm), in comparison to the average of the 5 minute trial, where the average eruption was 47 bricks (258.5 cm). Time from Bottle Opening to Mentos Drop 30 seconds 60 seconds 300 seconds

Trial 1

Trial 2

Average

61 bricks (335.5cm) 52 bricks (286 cm) 47 bricks (258.5 cm)

60 bricks (330 cm) 52 bricks (286 cm) 47 bricks (258.5 cm)

60.5 bricks (332.75) 52 bricks (286 cm) 47 bricks (258.5 cm)

Time of Carbonation Release Vs. Eruption Height 400

350

Eruption Height (cm)

300

250 Trial 1 Trial 2 Average

200

150

100

50

0 30

60

300

Time (seconds)

Conclusion This experiment examined the effect of the amount of time between opening of the Diet Coke bottle and the Mentos release. The data collected strongly supports the theory that the more time elapses between the opening of the bottle and the release of the Mentos, the less explosive the reaction will be. This is most likely the case because the longer the bottle is opened prior to the reaction, the more time carbonation (which might be a catalyst in the reaction) has time to escape.x Because the carbonation is significantly decreased, the reaction yields a shorter spray height. A follow-up experiment might be to compare sodas with different expiration dates, as the ones with nearest expiration dates will have sat on shelves longer and most likely be flatter (less carbonated). Another follow-up experiment could be 52


to buy a set of sodas with the same expiration date and perform the experiment at different times in relation to the expiration date; for example, one could be set off one month prior to the expiration date, another on the date, and a third one month later. x

Professor Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 551 (2008). x Professor Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 551 (2008). x Dr. H Brielmann, Guilford Journal of Chemistry: Introduction to the First Issue of the Guilford Journal of Chemistry, Page 4 (2008). x Professor Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 551 (2008). x Professor Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 551 (2008). x Carly Clark and Jenn Agamie, The Guilford Journal of Chemistry Volume I: How the Coatings of Mentos Affects the Size of the Mentos Eruption, Page 17 (2008). x Professor Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 551 (2008). x Professor Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 554 (2008). x Professor Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 552 (2008).

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Fruit Mentos Caused the Largest Explosion as Opposed to Strawberry and Green Apple Mentos Ashely Z and Katie N

Summary Coffey’s results support that the fruit Mentos created a larger explosion because their coating dissolves more easily in water.1 she also states that the mint Mentos went just as high as the fruit ones, but we did not test the mint Mentos. Although Both Coffey’s and our data support that the fruit Mentos cause the highest eruption, the Mythbusters data conflicts. They added their own waxy coating which covered the rough patches that would have otherwise been exposed.2 According to professor Coffey, Aspartame that is found in diet drinks is more explosive3, which is why we used diet coke in our experiment. We also used Diet Coke because it has more aspartame than the preservative potassium benzoate, which prevents the eruption from going higher.4 we tied our Mentos together so they would sink to the bottom faster. Tonya Coffey’s study previously proved that the farther the bubbles have to travel through the liquid, the higher the explosion will go5. This may be why that in Coffey’s experiments the crushed Mentos did not go as far, which is why we chose to keep them whole. She also states that there is not always a direct relation in the distance traveled through the liquid, shown by her test with the molecular sieve beads6. The fact that we put holes through the center of our Mentos may have also contributed because more of the rough surface was exposed, which is one of the most important causes of the diet coke reaction.7 Coffey also found that the hotter beverages cause a higher eruption, so we didn’t refrigerate ours and kept them at room temperature.8 54


Introduction One of the most well-known experiments for science classes is the easy experiment of Mentos and Coke. In this experiment, the height of the eruption was tested to see if different types of Mentos were effective and if tying the Mentos together would help weigh them down to produce a bigger eruption with the different Mentos. Fruit Mentos and Diet Coke were used because in Tonya Coffey’s article, she discovered that the fruit Mentos and Diet Coke were the most efficient in producing the highest eruption.9 the result of the experiment was that the fruit Mentos produced the highest eruption.

Experimental Section 1. Gather the required materials (Please see below). 2. Take 6 fruit Mentos and make a hole in the center of each of them using the specified nail. Then take the spool of thread and cut a thin piece of thread and string the 6 fruit Mentos together to make the Mentos fall to the bottom quickly. 3. Place 1 of the bottles of coke near the brick wall at a slight angle for measuring later and make sure that the bottle REMAINS CLOSED! 4. Very quickly, open the bottle, place geyser tube on top, and place Mentos in tube. Pull string out of the geyser tube to release Mentos and step away to prevent being sprayed. 5. Measure the height of the eruption based on the height of wetness of the wall. Either count the amount of bricks if using a brick wall and multiply that number by the length of the brick or use a long measuring tape and measure the height. Record data in cm. 6. Repeat once using fruit Mentos. Then repeat twice for each type of Mento using strawberry and green apple Mentos. Make sure that for each Mento type, there are 2 trials. Materials: 12 fruit Mentos, 12 green apple Mentos, 12 strawberry Mentos, a 2-inch 4-d (penny) nail, a spool of fine thread, pencil/pen, graph for recording data, 6 1L-bottles of diet coke, geyser tube, brick wall or hard surface to measure eruption height, measuring tape, and scissors to cut thread. Results The first trial that was performed was the first trial of the fruit Mentos. The eruption height of this was 198 cm which was the highest eruption and most spectacular recorded in this experiment. The second trial of fruit Mentos reached 181.5 cm. Next the green apple Mentos were tested and these produced very small wimpy eruptions compared to the fruit and strawberry Mentos. The first trial was 121 cm and the second trial was 154 cm. There may have been a minor error in the first trial due to the geyser tube (For more, please refer to the conclusion). The last set of trials was the strawberry Mentos. The strawberry Mentos landed in the middle of the results and yielded to relatively high eruptions. In the first trial, the eruption was 176 cm and the second trial height was 132 cm. In order of highest eruptions to smallest was fruit Mentos, strawberry Mentos, and then green apple Mentos. (For graph and table, please refer to end of paper.) Conclusion After completing this experiment, the results were that the fruit Mentos produced the highest eruption compared to the green apple Mentos and strawberry Mentos. The first trial may have had an error because the geyser tube was not all the way on and may have contributed to the lower height of eruption. The fruit Mentos may have had a rougher surface than the green apple Mentos, but another test would have to be done to confirm that hypothesis. The hypothesis stated before would make an excellent follow-up experiment to determine if that is the reason why the fruit Mentos went higher than the green apple and strawberry Mentos. Another follow-up experiment could be to try tying the Mentos in different ways to force them to the bottom quickly to determine if that has any effect on the eruption height of the Mentos.

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Endnotes 1. Coffey, Tonya. “Diet Coke and Mentos: What is really behind this physical reaction?” June 7, 2007: 554. 2. Coffey, Tonya. “Diet Coke and Mentos: What is really behind this physical reaction?” June 7, 2007: 554-555. 3. Coffey, Tonya. “Diet Coke and Mentos: What is really behind this physical reaction?” June 7, 2007: 554. 4. Coffey, Tonya. “Diet Coke and Mentos: What is really behind this physical reaction?” June 7, 2007: 554. 5. Coffey, Tonya. “Diet Coke and Mentos: What is really behind this physical reaction?” June 7, 2007: 555. 6. Coffey, Tonya. “Diet Coke and Mentos: What is really behind this physical reaction?” June 7, 2007: 555. 7. Coffey, Tonya. “Diet Coke and Mentos: What is really behind this physical reaction?” June 7, 2007: 556. 8. Coffey, Tonya. “Diet Coke and Mentos: What is really behind this physical reaction?” June 7, 2007: 556. 9. Coffey, Tonya. “Diet Coke and Mentos: What is really behind this physical reaction?” June 7, 2007: 552.

Trial 1

Trial 2

Fruit Mento

198 cm

181.5 cm

Green Apple Mento

121 cm

154 cm

Strawberry

176 cm

132 cm

Height of Eruption (in cm)

Height of Eruption with Different Types of Mentos 250 200

Tria l1

150

Tria l2

100 50 0 Fruit Mento

Green Apple Mento Type of Mento

Strawberry

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Period Seven

The weakening effects of Baking Soda and Sugar on the height of a Mentos in diet coke eruption The first time our group performed the experiment we tested how high five Mentos candies would erupt within a bottle of diet coke. We found that the average height at which it erupted was 131.5 cm. We came to this height by counting how many bricks the eruption went up, and measured the length of each brick in centimeters. Upon adding the baking soda and sugar to the diet coke, the eruption was much less impressive, since it hardly erupted higher than the top of the bottle, at about 11 centimeters for sugar and 8 centimeters for baking soda. The reason that it did not go that high was because by the time we got the Mentos into the coke, it had already begun to react. We can determine that the baking soda and sugar were both weakening factors to the eruption of the diet coke. Vinegar didn’t seem to alter the reaction as much, but it did make it go lower. The height of the eruption with vinegar was 76 centimeters. Introduction For our experiment we decided to verify Tonya Coffey’s results and test the effectiveness of adding baking soda to the diet coke. According to Coffey’s results, when she added baking soda to the soda it erupted to a height of 15.5 feet, or 472 centimeters.x We also wanted to see how sugar added to the soda would affect the eruption. We came to the conclusion that diet coke does not react as well with sugar or baking soda, because our resulting heights for those experiments were much lower than the control. When adding baking soda and sugar to the diet coke at the same time, we saw that each time, the bottle would overflow without adding any Mentos to it. Experiment Gather all Materials needed for the experiment Using a tube that can release objects with the pull of a string, and place five mentos within the tube. Open the diet coke, and as soon as possible place the tube over the coke and drop the mentos in, taking care to tilt the nozzle towards the wall so that the soda leaves a mark that can be measured Measure how high the soda shot upwards, and record the results; this will be your control Add 20 ml of vinegar to the soda and then put the nozzle on and repeat the process Add 20 ml of sugar to the soda and then put the nozzle on and repeat the process Add 20 ml of baking soda to the soda and then put the nozzle on and repeat the process Compile the data and graph it

Results We found through our experiments that baking soda and vinegar lessened the effects of the diet coke and Mentos eruption. Initially when we tested the diet coke it went up 48 bricks, which is equal to 131.5 centimeters. That was the average of three tests we performed. We came to the conclusion that adding sugar would decrease the reaction because when we added it, the soda overflowed before the Mentos even entered the soda, which made it go up only 11 centimeters. The addition of baking soda was equally as unsuccessful in increasing the reaction, because it reacted with the soda before the Mentos went in and only caused it to erupt 8 centimeters. However when we added vinegar we did get a successful reaction, for the average of the three trials was 27.5 bricks which is 76 centimeters. Graph

57


Effect of sugar, vinigar, and baking soda on the height of a mentos eruption 140 120

Height (cm)

100 80 Series1 60 40 20 0 Control

20 ml sugar

20 ml vinigar

20 ml baking soda

Things we added Conclusion

Since the results we found for these additions were harmful to the eruption, we can pretty safely determine that they do not make the coke more open to erupting. We did not think this would be the case, because according to Coffey, baking soda at least should have increased the reaction.x According to NASA even, adding a sugary substance to diet coke should create a reaction with the coke, which shows why we did get a small reaction after adding the sugar.x A possible reason we did not get strong results for when we just added the baking soda, vinegar, and sugar to the bottle is that there was too wide of a nozzle for the soda to escape from, which made it not go as high.x Also the reaction might have started as soon as the sugar was put into the coke, which would have made the mentos less effective.x An additional reason the baking soda might have caused the reaction to slow down, is because baking soda is a base which would take away the acidity of coke.x Also the amounts of coke and variables used were different then the ones done in other experiments, which must have some impact on the results of the experiment.x In the future, other people could place the soda bottle more carefully, or the pull the strings of the gyser more carfully so it doesn’t tip overx, make sure that the bottle wasn’t shaken around before performing the experiment,x and make sure that you’re using all the same flavor Mento’s for the same trial.x x Coffey, Tonya Shea. "Diet Coke and Mentos: What Is Really behind This Physical Reaction?" American Journal of Physics 76.6 (2008): 551. Print. x Coffey, Tonya Shea. "Diet Coke and Mentos: What Is Really behind This Physical Reaction?" American Journal of Physics 76.6 (2008): 551. Print. x Rust, Cashman R. "NASA ADS: Explosive Volcanism Lessons Learned from Mentos and Soda Eruptions." NASA Astrophysics Data Center. American Geophysical Union, 14 Nov. 2006. Web. 10 Oct. 2011.

Voltz, Stephen M. "Nozzle for Creating Geyser-like Fountains." USPTO Assignment Database. Frederick Globe, 21 Sept. 2007. Web. 10 Oct. 2011. x

x

Rust, Cashman R. "NASA ADS: Explosive Volcanism Lessons Learned from Mentos and Soda Eruptions." NASA Astrophysics Data Center. American Geophysical Union, 14 Nov. 2006. Web. 10 Oct. 2011. x Voltz, Stephen M. Effects of an Acidic Beverage on Dental Maintance 08th ser. 36.8 (1996): 1775-781. Antimicrobial Agents and Chemotheropy. American Society for Microbiology, 21 Oct. 1998. Web. 10 Oct. 2011. x Coffey, Tonya Shea. "Diet Coke and Mentos: What Is Really behind This Physical Reaction?" American Journal of Physics 76.6 (2008): 551. Print.

Voltz, Stephen M. Effects of an Acidic Beverage on Dental Maintance 08th ser. 36.8 (1996): 1775-781. Antimicrobial Agents and Chemotheropy. American Society for Microbiology, 21 Oct. 1998. Web. 10 Oct. 2011. x Rust, Cashman R. "NASA ADS: Explosive Volcanism Lessons Learned from Mentos and Soda Eruptions." NASA Astrophysics Data Center. American Geophysical Union, 14 Nov. 2006. Web. 10 Oct. 2011. x Voltz, Stephen M. Effects of an Acidic Beverage on Dental Maintance 08th ser. 36.8 (1996): 1775-781. Antimicrobial Agents and Chemotheropy. American Society for Microbiology, 21 Oct. 1998. Web. 10 Oct. 2011. x

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The Mixture of Mint and Fruit Mentos Produced the Largest Eruption Jack F and Jamie W

Summary The experiment being tested was if two mentos were dropped into a diet coke bottle, which one would have the highest eruption? The types of mentos that were used were fruit, apple, and mint; and the trials were two mint, two fruit, two apple, one mint one fruit, one mint one apple, and one fruit one apple. Two mint is considered the control due to it being the most common mento. If two mentos are placed into a diet coke bottle, then two fruit mentos will have the highest eruption because fruit mentos have a smoother shell, creating more pressure build up. Once the experiment was performed, one apple and one mint mento combination had the largest eruption, which was 46 bricks high. The next two highest eruptions were two mint mentos at 43 bricks, and one mint one fruit at 40 bricks high. Two apple mentos had the smallest eruption, which only went 27 bricks high. A combination that contained one mint went 100% as high as the control, where as a combination containing apple went 95.3% as high, and fruit went 88.3% as high as the control. Introduction The amount of mentos added to a bottle of diet coke will affect the size of the eruption. With each mento added to a bottle of diet coke, the height of the eruption spray rises proportionally.x Also, different mentos react differently with the diet coke. Fruit mentos are known to react and cause a larger spray than a mint mento would. This is because fruit mentos have a smoother surface, with fewer rough patches, which dissolves faster in the soda.ii Due to the short amount of time it takes for these to dissolve, carbon dioxide bubbles build up inside the bottle. The more buildup of the co2, the more pressure inside the bottle, which forces the soda out of the nozzle faster. x Experimental Section

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There were three different flavors of Mentos used, mint, fruit and apple; and a total of six different combinations, or trials. The trials were two mint, two apple, two fruit, one mint one fruit, one mint one apple, and one fruit one apple. These different combinations were placed into the nozzle compartment, and when released, dropped into the soda creating an eruption. The height of the eruption was measured in bricks. Procedure Obtain two mint Mentos, a nozzle compartment with pin, and a diet coke bottle Screw the nozzle compartment onto the diet coke bottle, and put the lock pin in place Place the two mint Mentos into the nozzle, secured by the pin Remove the pin, watch eruption and count the height in bricks Record data Repeat for each trial Supplies One pack of mint Mentos One pack of fruit Mentos One pack of apple Mentos One 6-pack of diet coke, 20oz per bottle A nozzle compartment with a loader pin Safety Precautions Always wear safety goggles Stand safe distance away Do not create too much pressure in the bottle, where it will explode Results 46

1 Mint 1 Apple 40

1 Fruit 1 Mint

36

1 Fruit 1 Apple

Height of Eruption (in bricks)

27

2 Apple

33

2 Fruit

43

2 Mint 0

20

40

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Mento Eruptions Results The combination of 1 mint and 1 apple mentos had the highest eruption. This eruption went 46 bricks high, 3 bricks higher than the height of the second eruption. The second highest eruption was 2 mint mentos, which went 43 bricks high. Next, 1 fruit and 1 mint mento had an eruption height of 40 bricks. From this point there was a drop off it eruption height. 1 fruit 1 apple mentos went 36 bricks, and 2 fruit mentos went 33 bricks high. Lastly, 2 apple mentos 60


erupted to only go 27 bricks high. The reaction between the 2 apple mentos was the only number that stood out as somewhat of an outlier. Conclusion After the conduction of the experiment to search for the perfect combination of Mentos flavors that would have the loftiest of height compared to the other combinations, Fitzgerald and Webb concluded that the grouping of the mint and apple flavored Mentos erupted the to a measure of forty-six bricks high. This result was followed by the combination of two mint Mentos (forty-three bricks high), mint and fruit Mentos (forty bricks high), fruit and apple Mentos (thirty-six bricks high), two fruit Mentos (thirty-three bricks high), and two apple Mentos (Twenty-seven bricks high). The reason for why the recipe of the mint and apple Mentos erupted the highest was partially because two mint Mentos in an explosion were second to the mint and apple candies in elevation. Besides the mint candy being the necessity for a perfect combination of Mentos for a large eruption, the ingredients in the mint and apple candies may have a simultaneous reaction with either each other or with the Coke itself.i Although the two apple candies went the lowest in altitude compared to the other dependant variables, it still combined for an extreme reaction with mint.ii Lastly, for further study, one might somewhat reenact this experiment by attempting to combine three, four or even more Mentos in order to find the arrangement for the perfect Coke and Mentos eruption. In conclusion, Fitzgerald and Webb discovered that the formula of apple and mint Mentos in a Coke and Mentos experiment were the ideal combination to achieve the highest rise of coke from the ground.

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Manipulating the Surface of Mentos: The Resulting Diet Coke and Mentos Explosion Height will Increase if the Increased Surface Roughness is Greater Than the Losses of Mass and Gum Arabic Juandiego C Summary: In this specific experiment, the surface texture was tested. However, it was discovered that it is extremely difficult to physically manipulate the surface texture of the Mentos without a resulting loss of mass and gum arabic. Therefore, three different groups with different surface roughness increase to mass/gum arabic loss ratios were tested to explore the resulting effects; one group of Mentos was grazed lightly with sandpaper, one had holes poked into it, and one had the coating completely scratched off- were tested. In comparison to the eruption height of a normal Mentos candy, the group with holes went 7% higher, the sandpapered one went 13% higher, and the one with no coating went 25% lower. Introduction: The diet coke and Mentos reaction is a fun experiment for physics and chemistry classes ranging in all different grade levels. The diet coke and Mentos candy eruption occurs when new Mentos are dropped into a freshly opened bottle of diet coke. The eruption can be multiple meters high (the record is 29.2 ft).1 This reaction was first shown on the Dave Letterman Show in 1999 and was the subject of a 2006 Mythbusters episode.2,3 There are few verified discoveries regarding the Mentos and diet coke eruption. Many experiments have inferred that additives, “viscous drag”, and temperature have a large impact on the explosion height. 4 However, it has been cited that surface roughness is a crucial factor of the reaction.5 When the Mentos candy falls to the bottom of the bottle, carbon dioxide bubbles form on it; then they detach and rise to the top. The bubbles act as nucleation sites for carbon dioxide still dissolved in the liquid. This discharges more carbon dioxide and creates a larger explosion.6 The higher surface area results in more growth sites present per unit volume. This theory is proven with Coffey’s experiment. Two of the combinations tested were Wint-o-Green Lifesavers and diet coke and rock salt and diet coke. The Wint-o-Green lifesavers had a rms roughness of 10 more than the rms roughness of rock salt. The Wint-o-Green’s higher surface area is one of the main factors that resulted in its explosion having more distance and losing more mass than the salt and diet coke. 7 In addition, an experiment done by Hill and Gaboury, two students of Guilford High School, showed that drilling holes into Mentos resulted in the eruption going higher than regular mentos.8 The intensity of the Diet Coke and Mentos eruption is moreover due to the presence of gum arabic in the Mentos candy coating.9 Gum arabic is a surfactant that increases the intensity of an explosion by reducing the surface tension of water.10 In Coffey’s paper, the presence of liquid gum arabic in Diet Coke soda caused a reaction without surface roughness.11 However, despite gum arabic’s important contribution to the explosive reaction between Diet Coke and Mentos, it is extremely hard to physically manipulate the surface area of Mentos candies without the losing amounts of it. The purpose of this lab is to further test the relation between these two properties behind the explosion. Experiment: In this experiment, we altered the surface of Mentos three different ways and then measured the height of the reaction between each Mentos and diet coke. We separated the green apple Mentos into four different groups to test our independent variable. With the first group we abraded the surface of the Mentos with sandpaper to create grooves in the surface. The second group we used sandpaper again to remove the candy coating of the Mentos completely, and the third group we used the metal tip of a mechanical pencil to make approximately ten holes in the front and back of the Mentos. The final group we kept the same to serve as a control group to compare the rest of our data to. The constants held in the experiment were the type of mentos, the size of the hole poked in the Mentos, the brand of soda, the bottle size, the extent of grazing on the first group of Mentos, and the number of Mentos used in each trial. After we prepared the Mentos we set up a 355 mL bottle of diet coke against a brick wall. We placed a flat whiteboard beneath the can to keep it from falling over and put soda lids in about a two inch stack under the side of the whiteboard away from the wall. This allowed the soda to splash onto the wall leaving a mark that would make measuring easier. 62


We placed two regular Mentos into a geyser and screwed the geyser on top of the open bottle just prior to the experiment to minimize the loss of carbon dioxide gas. 10 Then, we put on safety goggles, pulled the pin out, and stepped back a safe distance from the eruption. We recorded the number of bricks high the soda reached, and then repeated the step for multiple trials. We did the same procedure for the other three groups of Mentos. Results: The recorded heights for each type of Mentos can be observed in Table 1 and can be compared in Graph 1 or Graph 2. We conducted between three to six trails per type of Mentos. The average height for regular Mentos was 176.0 cm, 198.9 cm for sandpapered Mentos, 188.8 cm for Mentos with holes, and 132.0 cm for Mentos without the candy coating. We chose to use four significant numbers instead of the two that is required for the multiplication and division rules to increase the accuracy of our figures. The percent error for sandpaper is 0.008%, and the percent error for Mentos with holes is 0.03%. The other two groups divided equally as the average. The Mentos with holes in them had a resultant height 7% higher than the control group. The height of the sandpapered Mentos yielded an eruption height of approximately 13% higher than the control group on average, and the Mentos without coating had an eruption height about 25% lower than that of the control group.

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The Effect of Drop Height on the Height of the Mentos Eruption Summary: For our experiment, we dropped two mentos using 1 geyser tube, 2 geyser tubes, and then 3 geyser tubes to see if the height at which the mentos were released played a role in producing higher eruptions. Throughout the experiment we used the 473 milliliters of Diet Coke for every trial. The average height when using one geyser tube was 136 cm, two geyser tubes increased the height by 3.5 bricks making its average height of 158 cm, and three geyser tubes further increased the height with an average of 196 cm. The results also showed that there was a 16% increase when using 2 geyser tubes instead of 1, a 24% increase from 2 geyser tubes to 3, and a 44% increase from 1 geyser tube to 3 geyser tubes. At the end of the experiment, the results demonstrate that the higher the mentos are released the higher the eruption. Introduction: When the Mythbusters team tested the mentos eruption they found that the speed with which the sample falls through the liquid is a major factor in contributing to higher explosions. If the bubbles [produced during drop] must travel farther through the liquid, the reaction will be more explosive. Longer distances traveled by the bubbles result in more explosive reactions. In contrast, the mentos released from 1 geyser tube produce particles moving through the fluid at a slow speed, since they do not gain as much velocity, and do not travel as far down into the bottle. The Mythbusters further concluded that samples, which encounter less viscous drag and hence fall more quickly through the soda, will cause more explosive reactions. Experimental Section: This experiment is being used to see if the height of the drop of mentos has a noticeable effect on the height of a menots eruption. During this experiment, there will be three lengths of geyser tubes. 1 geyser tube, 2 geyser tubes taped together, and 3 geyser tubes taped together. These should be duck taped together very well to ensure that no cracks let eruption foam out of the sides. Results: The Effect of Drop Height on the Height of the Mentos Eruption Height of Eruptions (cm) Number of geyser tubesTrial 1 Trial 2 Trial 3 Trial 4 Average 1 152 152 127 114 136 2 158 158 152 165 158 3 190 215 177 203 196 Our data shows that the higher the mentos were dropped, the higher eruption it produced. For example, the average for the 1 geyser tube drop was 136 cm, the average for the 2-geyser tubes drop was 158 cm, and the average for the 3geyser tubes drop was 196 cm. This shows that as the height of the drop increased the eruption height of the mentos increases as well. There is no suspect data in this experiment because all of the numbers are close together for each height drop range. Experimental Procedure: These are the steps to follow in order to perform this experiment. It is important to have safety goggles on during the entire experiment. 1. Place 2 fruit Mentos in 1 geyser tube connected to the 16 oz. bottle of diet coke making sure they do not fall directly through. 2. Place the soda on a flat surface and then release the Mentos and record the height of the eruption. 3. Repeat steps 1 and 2 three more times 4. Gather 2 geyser tubes and connect the two with duct tape and then place the Mentos in the top tube making sure they stay in place. 5. Release the Mentos into the soda from a flat surface and record the height of the eruption. 6. Repeat steps 4 and 5 three more times 7. Now with 3 geyser tubes, connect all three of them with duct tape and drop the 2 fruit Mentos into the top tube. 8. Release the Mentos into the soda with a flat surface underneath and record the height of the eruption. 9. Repeat steps 7 and 8 three more times 64


Conclusion: At the end of the experiment, from the results that were collected, we discovered that the higher Mentos are dropped, the higher their eruption will be. The results from the experiment supported the Mythbusters theory from the work of Coffey because dropping the Mentos using 3 geysers tubes versus 1 geyser tube shows a significant difference in eruption height because the Mentos dropped from the top of 3 geyser tubes have more velocity; therefore, they fall farther down in the soda bottle. This is shown several times throughout the data because as it can be seen in the graph and table above, the height of the eruption is always higher for the higher drop distances. For example, in trial 2 for all of the heights, the 3-geyser tube drop is significantly higher than the other 2 drops with 1 and 2 geyser tubes In addition, in many of the trials, the data is never any close than 6 cm in height difference, which is a sizeable margin. If higher drop heights were tested, the data would most likely be linear because the height of the Mentos eruption would increase at a steady rate as the drop height increased and our data supports this concept. Perhaps at a certain drop height it could break the world record. The reason for these results could be that as the Mentos drop they gain more velocity, therefore creating a larger explosion. In the future, there could be multiple follow-up experiments to further solidify the position that the higher Mentos are dropped into diet coke, the larger eruption will occur. For example, there could be an extended experiment on this one that was performed, where the height is dramatically increased, and it tests how extreme the results can become.

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Mentos, Baking Soda, and Vinegar….A Quench to an Eruption’s Thirst. Rebecca E and Klaire C Summary The experiment completed consisted of using additives (baking soda and vinegar) to a soda and mentos eruption. The control of the experiment (1 mento and 1 bottle of soda) reached a height of 35 bricks. The first trial which consisted of ½ teaspoon of baking soda and 1 teaspoon of vinegar reached a height of 13 bricks. The second trial which had ½ teaspoon of baking soda and 2 teaspoons of vinegar reached 32 bricks. The third trial had ½ teaspoon of baking soda and 3 teaspoons of vinegar reached 13 bricks. And finally the fourth trial which had ½ teaspoon of baking soda and 4 teaspoons of vinegar reached a height of 0 bricks. Overall it was found that the more vinegar that was added to the mixture, the lower the eruption height was. Introduction The Mentos eruption is an experiment that can be changed in multiple ways. It has been seen on Mythbusters (3) and the David Letterman Show (4). Kids and adults of all ages have tried their own version of the “Diet Coke and Mentos” (10). Our experiment involved using additives (baking soda and vinegar) to see if it would increase the height of the eruption. We used baking soda at a constant of 2.5 grams and increased the amount of vinegar for each of the 5 trials. Robins and Turcio (2) had the same idea in which they referred to it is as a “volcanic eruption”. Diet Pepsi was found by Musterer and Ruotolo (1) to have a higher eruption than diet Coke. They determined that the additives almost entirely quenched the eruption. Cutler and Smith discovered that frozen mentos dramatically increase the eruption (7). The other resource we had, the article by Tonya Coffey, did not have any information about our specific experiment but it did have useful conclusions such as the higher temperature of the soda causes a greater eruption (6). The speed at which the mento is dropped is also a major factor in the eruption along with the idea that gum arabic and gelatin in mentos and potassium benzoate and aspartame in caffeine cause explosion (5, 9). In the experiment, there was a period of 15 seconds before the mento was dropped into the diet coke solution, therefore, adding water, sodium acetate, and carbon dioxide to the eruption. There was no information on these substances in our sources, but we can conclude that they altered the eruption because it added more to it. This made our experiment more complex than we had intended because there were five additives instead of the two that were intended. The additive creates the reaction NaHCO3 + CH3CO2H – CH3CO2Na + H2O + CO2. This reaction and the baking soda and vinegar solution quenched the overall eruption.

Experimental section Trial number Amount of baking soda Amount of Vinegar CONTROL 0 grams 0 teaspoons 35 bricks 1 (.5 teaspoon) 2.5g (1 teaspoons) = 4.9289 mL 13 bricks 2 (.5 teaspoon) 2.5g (2 teaspoons) = 9.8578 mL 32 bricks 3 (.5 teaspoon) 2.5g (3 teaspoons) = 14.7867 mL 13 bricks 4 (.5 teaspoon) 2.5g (4 teaspoons) = 19.7156 mL 0 bricks

Height of eruption

The experiment done here was based on using additives. The first step was to obtain (6) 8 oz bottles of diet coke, baking soda, white vinegar, a teaspoon, mint mentos, and a geyser tube. The first step in the process of the eruption was to run a control. This means nothing is added to the soda but a mento and a geyser tube, the string is pulled, and the height of eruption is recorded. Then the next step is to run the first trial of the experiment. The first step 66


is to cover the teaspoon in a coating of baking soda so that the spoon is half filled with baking soda. Then the vinegar is poured into the spoon and added into the soda. A minor eruption occurs here so waiting 15 seconds after the eruption helped to keep the experiment more accurate. Then a geyser tube is inserted into the soda with a mento into the soda and the height of eruption is recorded. For each trial, the amount of baking soda is constant but the amount of vinegar is increased. Now all steps can be repeated for each trial. Results *note: trial 1 is an outlier so that data will not be included in graphs. *note: all conversions were done online on Google calculator. ***note: observation: the more vinegar that is added the lower the final eruption will be

Conclusion With the provided data, it is suggested that if a constant amount of baking soda and increased amount of vinegar is added to a Mentos eruption, the more vinegar there is, the lower the eruption will be. The control in the experiment with no baking soda or vinegar went a height of 35 bricks. But as soon as more baking soda and vinegar was added, the eruption significantly lowered each trial, going from a height of 35 bricks, to 32, to 13, to no bricks. The amount of baking soda remained constant in every trial, but the amount of vinegar in each trial was increased. When at its maximum amount, the amount of vinegar was 4 teaspoons and there was no eruption, even with baking soda added to the mixture as well. This compares to the control of 35 bricks with no additives in the solution, making a difference of 35 bricks. Another comparison that can be made is to the third trial. The total eruption height was 32 bricks, as opposed to the end result of 0 bricks. It is very clear that the amount of vinegar in a Mentos eruption has a significant effect on eruption height, obviously lowering the overall eruption height. Now the question of why did this happen comes up. A potential reason as to why vinegar quenches the eruption could be because of an imbalance of baking soda and vinegar. In a typical baking soda and vinegar reaction, there is always a huge explosion but when the amounts of both additives are altered it could affect the explosion. Another thought as to why the vinegar could have affected the explosion is because the baking soda mainly caused a minor eruption in the soda by itself when it was first added to the mixture, so by adding the vinegar it could have caused a reverse reaction where it did the opposite of what it normally does in a typical reaction because soda is in the mix. Finally, if the experiment was done over again more trials would be added for more data points, more accurate measurements would be taken, more precise procedures would also be taken to prevent invalidity of data, and more additives and background research would have been done to get a more clear understanding of the experiment before it was started. Citations 7. Rachel Cutler and Emma Smith, Guilford Journal of Chemistry, Volume 1, Pages 6-12 (2007). 1.Angelise Musterer and Lindsay Ruotolo, Guilford Journal of Chemistry, Volume 2, Pages 12-14 (2008). 2. Kelsey Robins and Laura Turcio, Guilford Journal of Chemistry, Volume 2, Page 38 (2008) 3. Mythbusters. Videocassette. Discovery Channel, 2006. 4. The Late Show with David Letterman. Videocassette. CBS, 1999. 5,6,8,9,10: Tonya Coffey, Diet Coke and Mentos: What is Really Behind This Physical Reaction?

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Which Soda Provides the Best Mentos Eruption; Diet Coke, Sierra Mist, Mountain Dew Rebecca E and Klaire C

Coke Zero, Diet Pepsi, Sprite, Club Soda: Summary: For this Mentos Eruption, the sodas used were Diet Coke, Sierra Mist, Mountain Dew, Coke Zero, Diet Pepsi, Sprite, Club Soda, the goal was to see which soda produced the highest eruption. This variation of soda helped the observer see how different variables directly affect the height of the sodas eruption. This experiment the researchers found that Diet Coke caused the highest eruption out of all the sodas tested with an average of six bricks or thirty-three centimeters. Mountain Dew, Sprite, and Club Soda all fell short with an average of two bricks or eleven centimeters. Coke Zero came in second with an average of five or twenty-seven and a half centimeters. Diet Pepsi came in third with an average of four bricks, or twenty-two centimeters. This directly contradicts the work of Angelise M & Lindsay R. Through all this data a mathematical formula can be created where X is equal to the soda and Y equals the height and Y=X. Introduction: In earlier tests done by other researchers to find the soda that provides the best soda eruption, Diet Coke had been used. In this experiment the data shows that is because it does, in fact provide the best Mentos eruption. In an experiment done by Tonya Shea Coffey1, Coffey’s data supports the facts of “Which soda provides the best Mentos eruption; Diet Coke,” where Diet Coke provides the best Mentos eruption. Yet, when this data was compared with “Diet Pepsi –Not Diet Coke – Produces Highest Results in Mentos Eruption When Compared to Other Diet Carbonated Drinks” By Angelise & Lindsay R, it was found that the data was not supported and Diet Pepsi had the highest eruption. In the “Introduction to the second issue of the Guilford Journal of Chemistry, M and R’s3 data on Diet Pepsi is said to be 100% higher relative to Diet Coke. In another study, “The Effect of Soda Type on the Height of Mentos Eruptions,” by Ethan S and Zack B, data supported the data of “Which Soda Provides the Best Mentos Eruption; Diet Coke, Sierra Mist, Mountain Dew Coke Zero, Diet Pepsi, Sprite, Club Soda: Diet Coke!” with Diet Coke being Shore and Browns’5 highest soda eruption too. The experiment “Which Soda Provides the Best Mentos Eruption; Diet Coke, Sierra Mist, Mountain Dew, Coke Zero, Diet Pepsi, Sprite, Club Soda: Diet Coke!” used strawberry, fruit, Mentos, which Coffey1 found to help make the largest eruption. In an experiment completed by Allison F and Jess L, they found that mint Mentos and Fruit Mentos have the same size eruptions. In an experiment in the American Journal of Physics, Fruit and Mint Mentos were found to have the same size eruptions also. Unlike K and R from the “Introduction to the Second Issue of the Guilford Journal of Chemisty,” the experiment, “Which Soda Provides the Best Mentos Eruption; Diet Coke, Sierra Mist, Mountain Dew, Coke Zero, Diet Pepsi, Sprite, Club Soda: Diet Coke!” did not cut the Mentos in half before adding them into the soda, they kept them whole. Experimental Section: The experiment that was done, by Rebecca E and Klaire C, was accomplished by having three trials, per soda, completed. With-in each trail a single Mento was dropped into a freshly opened bottle of twelve-milliliter bottle of soda. Results: Trial 1 Trial 2 Trial 3 Diet Coke 33 cm 33 cm 33 cm Sierra Mist 16.5 cm 11cm 11 cm Mountain Dew 5.5 cm 11 cm 16.5 cm Coke Zero 33 cm 27.5cm 22 cm Diet Pepsi 16.5 cm 22 cm 27.5 cm Sprite 11 cm 11 cm 11 cm Club Soda 22 cm 0 cm 11 cm (Each Brick is equal to 5.5 cm)

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Conclusion: For our experiments, we found that out of the seven sodas we used, Diet Coke worked the best. For all three of the trials, Diet Coke’s foam shot up an average of 6 bricks, 33cm. The soda that had the next largest foam height was Coke Zero with an average of 5 bricks, 27.5cm and the third largest foam height was Diet Pepsi with 4 bricks, 22cm. According to Ethan S and Zack B, Diet Coke had the second largest explosion with an average of .85m and Sprite had the 3rd largest explosion, with an average of .51m1. Our results are not completely accurate because the first day of experimenting we did not have a string so we had to substitute a stick for it. The stick could have had a negative effect because it was thicker than the one attached to the string that we used the second day. Also, when we pulled both the sting and the stick sometimes the soda would fall over causing the data to be not as accurate as it could have been. “Sometimes, my hand partially hit an explosion, perhaps causing the height to drop” 2, like the picture shows on the right. The same thing happened in our experiment as well. A follow up experiment would be to try the different sodas with a different type of Mentos to see if the different flavors have an effect with the sodas. Something else we could do, would be to try less types of soda and do more trials to get our data more accurate. Experimental Procedure: 1. Get 12 ounce bottles of Sprite, Coke Zero, Diet Coke, Diet Pepsi, Club Soda, Mountain Dew and Sierra Mist as well as Mentos. 2. Open bottle and attach the geyser tube. Attach the string and drop the Mento in. 3. Pull the string and measure how high the foam goes. Record it in a data table. 4. Repeat steps 2-3 for each bottle. Endnotes: 1.“Diet Coke and Mentos: What is really behind this physical reaction?”, Tonya Shay Coffey. Received 7 June 2007; accepted 5 February 2008. Pages: 551, 552, 553, 556. 2. “Guilford Journal of Chemistry” (First- Second Issues) Editor and Chief: Dr. H. Breilmann. Pages: 1,2,3,4 3. “Diet Pepsi –Not Diet Coke – Produces Highest Results in Mentos Eruption When Compared to Other Diet Carbonated Drinks”, By Angelise M & Lindsay R http://chemistryadventure.com/Documents/b2.%20Diet%20Pepsi,%20not%20diet%20coke%20is%20the%20highest.pdf 4. “Cinnamon Mentos Erupt 20% Higher than Mint Mentos”, By Allison F and Jess Lhttp://chemistryadventure.com/Documents/b1.%20Cinnamon%20Mentos%20Erupt%2020%20percent%20higher.pdf 5. “The Effect of Soda Type on the Height of Mentos Eruptions”, By Ethan Sand Zack B. http://chemistryadventure.com/Documents/b9.%20The%20Effect%20of%20Soda%20Type%20on%20the%20Height%20 of%20Mentos%20Eruptions.pdf

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1


Table of Contents Period 2 Jacob H, Ben B, Colton S The Effect of Different Sodas on the Height of a Soda and Mentos Eruption Craig A The Effect Various Mentos Has on Diet Coke Courtney O The Colder the Temperature of Coke the Higher a Mentos Eruption Anny Y Mint Mentos Erupt 16% Higher Than Strawberry Mentos and 55% Higher Than Green Apple Mentos with Diet Coke Anna K Increased Temperature of Diet Coke and Number of Mentos Increases the Height of Mentos Eruption Ambur D Two Bottles of Diet Coke Connected to Make One Eruption Will Heighten the Eruption Compared to a Single Eruption Period 3 Catherine D The weakening effects of Baking Soda and Sugar on the height of a Mentos in diet coke eruption Claire W and Lindsey U Mentos Soaked in Club Soda Prior to Trial Will Cause the Highest Eruption Shane G and Clara P How the Size of the Hole in the Nozzle Affects the Height of a Coke and Mentos Eruption Jenna P The height of the Mentos eruption depends on the outside coating Marguerite D and Alex P Diet Coke vs. Energy Drinks Period 4 Sara D and Alexa B Crushing Mentos will not make the eruption larger Andrew T and Mark L Mentos Car Eruption Michael G Diet Pepsi and Mentos: Elongated Eruptions

2


Period 5 Ben E Drilling holes in the Mentos will increase eruption height Dan F and Samuel W The Effect of the Height of Introduction of the Mentos into the Diet Coke on the Severity of the Reaction

Evan H and Michel I Smaller Nozzle Size Creates Larger Spray during the Mentos Eruptions Grace I and Amanda M High Surface Area Increases a Coke Mentos Eruption Height Olivia S and Bronwyn R The Amount of Time between Opening a Bottle of Diet Coke and the Mentos Release Affects the Size of the Eruption Ashely Z and Katie N Fruit Mentos Caused the Largest Explosion as Opposed to Strawberry and Green Apple Mento Period 7 Jack F and Jamie W The Mixture of Mint and Fruit Mentos Produced the Largest Eruption Kate C., Anny Y., Annie X. Manipulating the Surface of Mentos: The Resulting Diet Coke and Mentos Explosion Height will Increase if the Increased Surface Roughness is Greater Than the Losses of Mass and Gum Arabic Juandiego C Manipulating the Surface of Mentos: The Resulting Diet Coke and Mentos Explosion Height will Increase if the Increased Surface Roughness is Greater Than the Losses of Mass and Gum Arabic Rebecca E and Klaire C Mentos, Baking Soda, and Vinegar‌.A Quench to an Eruption’s Thirst Zoe B and Nicole B Which Soda Provides the Best Mentos Eruption; Diet Coke, Sierra Mist, Mountain Dew Coke Zero, Diet Pepsi, Sprite, Club Soda

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The Effect of Different Sodas on the Height of a Soda and Mentos Eruption Jacob H, Ben B, Colton S

Summary For our experiment, we decided to test eight different types of soda to see how high their respective Mentos-induced eruptions would be, if any eruptions would even occur at all. The sodas that we used were Diet Pepsi, Seltzer, Grape Soda, Diet Coke, Sprite, Coca-Cola, Pepsi Max, and Coke Zero. We expected Diet Coke to produce the highest spray at 533.5 cm simply because this soda is the one most famously used in this experiment. However, Coke Zero surpassed the Diet Coke by 27.5 cm, achieving an astonishing height of 561 cm. In order from the highest spray to the lowest spray; Coke Zero (561 cm), Diet Coke (533.5 cm), Diet Pepsi (473 cm), Coca-Cola (434.5 cm), Sprite (363 cm), and Grape Soda (247.5 cm). Our two remaining drinks, the Seltzer and Pepsi Max, are unable to be compared to the other drinks because both tests involving these drinks failed. The Seltzer fell over mid-eruption and the Mentos became lodged in the geyser tube for the Pepsi Max. Introduction The Mentos Eruption Experiment has become a worldwide phenomenon ever since the first videos of this experiment started showing up on YouTube. Then, in 2006 the Discovery Channel show “Mythbusters” tackled the experiment themselves. Despite all of the publicity and attention this simple experiment has achieved, only one scientific paper has been written, reviewed, and published to the scientific community. In this paper, Tonya Coffey conducts the Diet Coke and Mentos experiment using a variety of sodas and potential reagents. At the end of her paper, Coffey concludes that potassium benzoate and aspartame are two main reagents that cause the eruption. She also concluded that the surface roughness of the reagents and the temperature of the sodas are major components in the reaction as well.1 Experimental Section Materials: 2 liter bottles of Diet Pepsi, Seltzer, Grape Soda, Diet Coke, Sprite, Coca-Cola, Pepsi Max, and Coke Zero at room temperature; 72 individual Mentos; a geyser tube; a damp rag for cleaning 1. Load 9 Mentos into the geyser tube and sure the pin and slider. Make sure the components won’t accidentally slip. 2. Unscrew the top of a soda bottle and quickly place the geyser tube into the bottle. Secure the tube to the bottle. 3. Place the bottle next to a wall or some device capable of measuring the height of the eruption. Angle the bottle approximately 80 degrees, pointing toward the wall. 4. Hold the bottle tightly to prevent it from falling over and pull the pin out of the geyser tube in a smooth, quick motion. Continue to hold the bottle throughout the eruption to prevent it from tipping. 5. Measure the height of the soda on the wall and record your data. 6. Use the damp rag to clean out the tube after the eruption to prevent the new Mentos from sticking to the inside of the tube. 7. Repeat steps 1 through 6 using each individual soda for as many trials as desired. Results Diet Grape Diet Sprite CocaCoke Pepsi Soda Coke Cola Zero Height of 473 cm 247.5 cm 533.5 cm 363 cm 434.5 cm 102 cm Eruption

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Height of Mentos Eruptions with Different Sodas 600 500 400 Height of Eruption 300 (cm) 200 100 0 Diet Pepsi

Grape Soda

Diet Coke

Sprite

Coca-Cola

Coke Zero

Types of Soda

Conclusion After conducting the experiment, we found that Coke Zero achieved the highest eruption. As for a scientific explanation for this result, we cannot provide one. The ingredients in Coke Zero are very similar to the ingredients in Diet Coke; they both contain aspartame and sodium benzoate, which Coffey found to be the major reagents in this reaction so as to why the Coke Zero achieved a higher eruption is unknown. It is also impossible to determine whether the data associated with any of these sodas is consistent because only one trial was conducted with each type of soda, so these results could have just been a random occurrence based on any number of factors. However, given the potentially flawed data as they are, general assumptions can be made. It appears that since the diet drinks (Coke Zero, Diet Coke, and Diet Pepsi) had the top three highest eruptions, something must be present in these three drinks that causes them to be particularly volatile when exposed to Mentos as opposed to the other drinks which still reacted to the mints, but not nearly as explosively. In addition to the potential for the data above to be flawed, it should also be noted that two other drinks, Seltzer and Pepsi Max were tested. However, these drinks were not included in the results because both tests malfunctioned and a reliable height measurement could not be obtained so it would be inappropriate to attempt to compare these two errors to the above data. A relevant follow-up experiment to ours could be conducted using the same sodas, however more trials for each soda should be performed in order to reveal if our data truly was flawed or semi-random; also additional trials would eliminate the need to exclude data because of failed trials such as ours. Endnotes Tonya Shea Coffey. “Diet Coke and Mentos: What is really behind this physical reaction?� 2008 Angelise Musterer and Lindsay Ruotolo. The Guilford Journal of Chemistry. Volume 2, pages 12-13 (2009). Another paper discussing a very similar experiment to ours in which they changed the types soda as well. 1

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The Effect Various Mentos Has on Diet Coke: Craig A

The mentos and coke experiment has become a wide known result. You drop a few mentos into diet coke and out comes a geyser of coke spraying out the top. But this experiment took the mentos and used different types of mentos to test the variable height of each type. In this experiment there was mint and fruit mentos present. The mint sprayed, at best, 54 bricks high (or 108 inches because one brick is two inches tall). The fruit sprayed, at best, 81 bricks high (or 162 inches high). So this proves that the fruit creates a more powerful geyser than the mint. Also in the experiment performed by the college student, Coffey, she had the fruit mentos producing an explosion of a greater distance than the mint mentos.1 They had stating that the fruit mentos burst 17.8 feet, while the mint mentos went 16.3 feet.2 In the experiment performed by Tonya Shea Coffey, she had mint mentos exploding a shorter distance than the fruit mentos.3 The mentos and diet coke experiment that was performed in this experiment produced results showing that different mentos do, in fact, produce different geyser heights. If different mentos produced different outcomes then different mentos must have different make-ups because they would produce the same outcome if they were the same in their make-up. With the background research in mind the mentos experiment was predicted to be only slight differences between the different mentos. Because the mentos have numerous tiny pores in the surface layer of the candy the coke, in reaction, releases carbon dioxide at a very rapid rate. This is what causes the geyser of soda to erupt.4 What also ignites the geyser is the gelatin and gum arabic inside the mentos. The gum arabic and the gelatin cause the foam to form in the soda.5 In our experiment the fruit mentos went higher than the mint mentos proving that there is a difference in the two mentos. That difference caused as much as a 50 inch difference in height, in the explosion. Materials: 2 pairs of safety goggles 4 bottles of 2 litter diet coke 2 rolls of mentos: o Fruit o Mint 2 geyser tubes (didn’t know what to call them) Safety:  Be sure to wear your safety goggle at all time when handling the products.  Be sure clear a good distance before during and after the explosion.  Be sure to make the dropping of the mentos to be fluid and quick/make sure they won’t get stuck and not fall in, but fall in later.  Be sure to not drink the soda or eat the mentos after the experiment. 1

Diet Coke and Mentos: What is really behind this physical reaction? By Tonya Shea Coffey ~ Coffey’s results show that the mint

mentos are less powerful than the fruit in the explosion. 2

Diet Coke and Mentos: What is really behind this physical reaction? By Tonya Shea Coffey ~ those numbers are from the packet

given to us by you. 3

Diet Coke and Mentos: What is really behind this physical reaction? By Tonya Shea Coffey ~ it was 2.5 feet of a difference.

4

Wikipedia: Mentos and Diet Coke ~ CO2 was released due to these pores. I found this fact on Wikipedia.

5

Wikipedia: Mentos and Diet Coke ~ I found that these were ingredients in the mentos on Wikipedia.

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Procedure: 1) Place safety goggles on your face. 2) Set your mentos into the tube, ready for the drop. 3) Place tube onto the diet coke. 4) Set up the coke so it is tilting just slightly towards the building, ready to move on to pull the string. 5) Pull the string and run a little away from the explosion to avoid the explosion. 6) Record observations. 7) Repeat the steps 2-5 for continuing trials and variables Heights: Trial 1: Trial 2: Fruit: 81 bricks 20 bricks: 202.5 inches 50 inches  There was a loose geyser tube and it exploded. Mint: 54 bricks 47 bricks 135 inches 117.5 inches

250

200

150 Trial 1 Trial 2

100

50

0 Fruit

Mint

This table shows that the experiment proved our hypothesis. The fact that there was such a difference in the heights shows that there is a different make-up between the two. A 202.5 inch height to a 135 inch difference is a significant difference when discussing the height. But when discussing the amounts lost, such as in Coffey’s experiment, there was 1440g lost from fruit mentos, and 1410g lost from the mint mentos.6 These results signify our successful completion of proving our hypothesis. The graphs and tables in Coffey’s lab prove and support our prediction as to how the mentos will affect the coke. They have small and 6

Diet Coke and Mentos: What is really behind this physical reaction? By Tonya Shea Coffey ~ That is only 30g which is a really small

amount.

7


large differences in the mint and fruit conclusions.7 The experiment performed in this class has proof only with height. So the data is could have been expanded in so many ways, such as we could have had a third trial, or we could have had another kind of mentos. We could have also done left over in the can comparisons, eruption power comparisons, or types of soda. The geyser tube blew off so that changed our results and we got less reportable results. The table and graph are not as correct as they would have been had there not have been a mistake in the experiment.

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Diet Coke and Mentos: What is really behind this physical reaction? By Tonya Shea Coffey ~ Some data concludes that the fruit is

much more powerful, but in other cases the fruit is less of an outlier from the mint.

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The Colder the Temperature of Coke the Higher a Mentos Eruption Courtney O

Our group tested the effect of temperature on the height of a Mentos eruption. We wanted to see if the coldness of the coke would make the eruption higher. We discovered that the colder the coke the higher the eruption was. When our coke was room temperature or 71 degrees Fahrenheit it erupted to an average of 30 bricks. When our coke was chilled at a temperature of 46 degrees Fahrenheit it erupted to an average of 33 bricks. When our sample was cooled down to 37 degrees Fahrenheit it erupted to an average of 34.5 bricks. This shows that cold soda does cause for a higher eruption but the difference between the chilled and cold soda is not very much. The percentage increase from room temperature to 46 degrees is 9%. Meanwhile the percentage increase from 46 degrees to 37 degrees is only 4%. This shows us that once the soda is cold it doesn’t have as much as an effect because the difference between the chilled and cold soda is not nearly as big a percentage between the room temperature and the chilled coke. The coke and Mentos experiment occurs when Mentos are dropped in a fresh bottle of coke and results in an eruption from the coke bottle. Depending on many different factors the height of the eruption can greatly vary. An experiment involving temperature was conducted by Cutler and Smith who showed that the height of the eruption could be dramatically increased by the freezing of the Mentos candies. This is similar to the experiment we conducted because it involves the coldness of the materials used. They also found similar results to ours showing that the coldness makes the eruption higher but after a certain point it doesn’t make as great of a difference. In the article written by Tonya Shea Coffey about what is really behind the physical reaction involved in a Mentos eruption he talks about how varying temperatures of soda cause the mass to vary which may show why an eruption is higher when the soda is colder. The lack of mass in the colder sodas could show the reason why we got the results we did, with the colder bottles of coke creating the highest eruption. When conducting a coke and Mentos experiment to see how temperature affects the height of the eruption you need to have a total of forty-five Mentos and nine bottles of soda to carry out the experiment accurately. You will also need a geyser tube and a way of measuring how high your eruption goes, such as a wall. The first thing you need to do is put six bottles of soda into the refrigerator waiting for three of these bottles to reach a temperature of 8 degrees Celsius and the remaining three to reach a temperature for 3 degrees Celsius. The three bottles you kept out of the refrigerator will be your control or room temperature samples and should be around 22 degrees Celsius. Once you have all your sodas at the proper temperature you put five Mentos into a geyser tube, line your soda up against your wall and drop the Mentos into a freshly opened bottle of soda. Repeat this for all nine bottles, so that you do each temperature three times. Find the average of this data and you will see if how cold the soda is affects the height of a Mentos eruption. Temperature ⁰C 22⁰C 8⁰C 3⁰C

Trial #1 32 bricks 33 bricks 32.5 bricks

Trial #2 28 bricks 35 bricks 36 bricks

Trial #3 31 bricks 31 bricks 35 bricks

Average 30 bricks 33 bricks 34.5 bricks

These results show that the colder the temperature of a bottle of coke the higher a Mentos eruption goes. This is significant because it shows that a temperature change has a certain effect on the eruption. A great follow up experiment that could be done would be how the eruption would be affected if you heated up the soda as opposed to cooling it down. If this experiment was conducted following the experiment where the soda was cooled down then you could see how temperature affects Mentos eruptions on a much bigger spectrum. This experiment was relatively reliable, and issue being that some of our sodas were on the wrong angle with the wall and one even fell down. For these reasons out experiment could not be called completely valid. Although when our sodas fell over and hit the wall the wrong way we repeated these bottles and got more valid results. The difference in these temperatures did not prove to be huge but definitely had somewhat of a difference. Since the change in height from room temperature to 8 degrees 9


Celsius was 9% this proves that there was some height involving the change in temperature. Meanwhile the change from 8 degrees Celsius and 3 degrees Celsius was a lot less drastic with a change in height of only 3%. For this reason it cannot definitely be proven that there is a huge difference between 8 degrees Celsius and 3 degrees Celsius. Some other interesting articles involving Mentos eruptions are about the discoveries made by Marsh and Moalli who kept and eruption going for 40 seconds and how Federici and LaChance found that cinnamon Mentos erupted 20% higher than any other flavor. 1. 2. 3. 4. 5.

Gather Materials- 45 Mentos, 9 bottles of coke, geyser tube, way of measuring Make 3 bottles of coke room temperature (22â °C) make 3 bottles 8â °C and make 3 bottles 3â °C. Put 5 Mentos in a geyser tube and align coke bottle with measuring tool. Drop Mentos into the bottle and record results Repeat this for each of the nine bottles

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Mint Mentos Erupt 16% Higher Than Strawberry Mentos and 55% Higher Than Green Apple Mentos with Diet Coke Anny Y I. SUMMARY The purpose of this experiment was to investigate which flavor of mentos created the highest eruption with diet coke. There were three different flavors of mentos tested: mint, strawberry, and green apple. There were two trials performed for each mentos flavor. The height of the eruptions was measured by counting the amount of bricks the eruption’s spray reached on the side of a building. The results, in meters, were calculated by the formula: height of 1 brick=2.25 inches=0.05715 meters. The results for the mint mentos were 4.7 meters (82 bricks) and 4.0 meters (70 bricks) with an average of 4.35 meters. The results for the strawberry mentos were 3.4 meters (60 bricks) and 3.9 meters (68 bricks) with an average of 3.65 meters. The results for the green apple mentos were 1.9 meters (34 bricks) and 2.0 meters (35 bricks) with an average of 1.95 meters. These results show that the mint mentos erupted 16% higher than the strawberry mentos [use of formula: 1 – (3.65/4.35) = 0.1609 ] and that the mint mentos also erupted 55% higher than the green apple mentos [use of formula: 1 – (1.95/4.35) = 0.5517 ]. II. INTRODUCTION Diet coke-mentos eruptions are becoming a popular experiment in the world of science. The experiments include dropping about 5-10 mentos into usually a 2 L bottle of diet coke. The result is a large eruption of the diet coke spray, which is referred to as a geyseri. Interestingly enough, the mentos reaction is said to be a physical reaction and not a chemical one because when the mentos hit the soda, bubbles are formed over its surface, and the liquid is pushed out of the bottle in a violent eruptionii. What specifically causes the enormous eruption is still being investigated. Professor Coffey of Appalachian State University performed the mentos experiment, but first investigated the popular Mythbusters team’s experimental claims and eruptions which are posted all over the internetiii. Coffey’s report states that the Mythbusters correctly identified aspartame and potassium benzoate as the two key ingredients to set off the large eruptionsiv. The report also acknowledges different variable that may have an effect on the eruptions. It’s interesting to see just how many ways the experiments can be formed and what information can consequently be pulled from them. For example, not only diet coke has to be used in an eruption. Musterer and Ruotolo from The Guilford Journal of Chemistry conducted experiments and discovered than diet pepsi created an eruption 100% higher than that of the diet cokev. Another interesting experiment was that of Taylor and Schaffer, who discovered that a melted mentos will erupt at a slow rate that can sustain for hoursvi. This is very different from the other experiments because it measures not the height of an eruption, but how long it sustains for. Similarly, the experiment by Earles and Graham suggested that eruption power should be measured by volume of the eruptionvii. In their findings, the remaining soda volume for many soda sizes was constant which suggests that there is a fixed relationship between soda size and eruption volumeviii. Another experiment by Feldman and Monte, suggested that the more mentos added to the experiment, the higher the eruptionix. A final experiment similar to the one explored in this lab is that of Federici and LaChance, which suggested that cinnamon mentos eruptions are 20% higher than mint mentos eruptionsx. III. EXPERIMENTAL SECTION / PROCEDURE There were three levels of the independent variable in this experiment, which were mint mentos, strawberry mentos, and green apple mentos. There was no control in this experiment. The constants in this experiment were the amount of diet coke used in each eruption (2 L), the amount of mentos used in each eruption (10 mentos), and the distance from the diet coke bottle to the wall (1 ft). The dependent variable was the height of the eruption, measured in bricks and then converted into meters. Materials for the experiment included 6 2 L bottles of diet coke, 2 rolls of mint mentos, 2 rolls of strawberry mentos, 2 rolls of green apple mentos, an eruption chamber (dry). The procedure used to perform this experiment was: 11


Place 2 L diet coke bottle 1 foot from the brick wall and angle slightly toward the wall so that the spray will hit the wall but still reach maximum height. Open the eruption chamber tube and insert 10 mint mentos. Close the tube. Open the diet coke bottle and quickly screw the eruption chamber onto the top of the bottle until it is completely tight. Pull the string on the side of the chamber to release the mentos into the diet coke, and step back. Observe the eruption and count how many bricks tall the eruption reached. Repeat steps 1-5 with a dry chamber for a second trial. Repeat steps 1-6 with the strawberry mentos. Repeat steps 1-6 with the green apple mentos. Record all data and convert brick measurements into meters using formula: 1 brick=2.25 inches=0.05715 meters.

IV. RESULTS The results for the mint mentos were: trial #1- 4.7 meters (82 bricks); trial #2- 4.0 meters (70 bricks); an average of 4.35 meters. The results for the strawberry mentos were: trial #1- 3.4 meters (60 bricks); trial #2- 3.9 meters (68 bricks); an average of 3.65 meters. The results for the green apple mentos were: trial #1- 1.9 meters (34 bricks); trial #22.0 meters (35 bricks); an average of 1.95 meters.

Height (cm)

Average Height 600 500 400 300 200 100 0 Average

Type of Soda

12


5 4.5

Mint Mentos Erupt 16% Higher Than Strawberry and 55% Higher Than Green Apple

Height of Eruption (meters)

4 3.5 3 Trial 1

2.5

Trial 2

2

Average 1.5 1

0.5 0 Mint Mentos

Strawberry Mentos

Green Apple Mentos

Type of Mentos

V. CONCLUSION The results found in this experiment show that mint mentos had an average eruption 16% higher than strawberry mentos, and also an average eruption 55% higher than green apple mentos. The reason for these results could be due to different textures of the different flavored mentos, the different ingredients used for the different mentos, a different level of gum arabic in the mentos, or many other explanations. Ultimately, this experiment cannot provide a reason for the results. These results are not so significant that it would be assumable that mint mentos cause the highest diet coke-mentos eruptions. The validity of the experiment is not exemplary due to the amount of variables present in the experimental conditions. For example, there was no constant launching angle that the diet coke bottle was placed in. This would have affected height of the eruption sprayed on the bricks, because it would have angled the line of spray differently for each trial. A future recommendation to avoid this issue would be to set up a similar experiment but with a fixed launching angle of 40 degrees between the bottle and the ground near the wall. Another variable that could have poorly affected the results is the different time periods after opening the diet coke bottle. Between opening the bottle and letting the eruption go off there is a period of time where CO2 gas is leaking out of the soda. This would have affected the experiment by making the eruptions that had a longer time period weaker than those that had a shorter time period. A future recommendation to avoid this issue would be to set up a similar experiment but with a fixed amount of time of 15 seconds recorded and issued by a stopwatch between the opening of the soda bottle and the actual eruption.

i

Account of mentos-like eruptions dating back to the 1980s with an interview of Steve Spangler at http://www.rimmkaufman.com/blog/steve-spangler/21122007/ ii Steve Spangler article about what happens to the ingredients during a diet coke-mentos reaction at http://www.stevespanglerscience.com/experiment/original-mentos-diet-coke-geyser iii Mythbusters’s mentos experiments recorded in video at http://dsc.discovery.com/videos/mythbusters-diet-coke-andmentos.html iv Tonya Shea Coffey report on what is behind the mentos reaction and the validity of the Mythbusters’s claims at http://tnst.randolphcollege.edu/apply10/inst_mats/handouts/EnvSc/Coffey08_diet_coke_and_mentos.pdf v Angelise Musterer and Lindsay Rutolo, Guilford Journal of Chemistry, Volume 2, Pages 12-14 (2008). vi Sam Taylor and Will Schaffer, Guilford Journal of Chemistry, Volume 2, Page 38 (2008).

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Kaitlyn Earles and Megan Graham, Guilford Journal of Chemistry, Volume 2, Pages 21-22 (2008). Dr. H. Brielmann, The Guilford Journal of Chemistry, Volume 1, pages 4-5 (2008). ix Matt Feldman and Alex Monte, The Guilford Journal of Chemistry, Volume 2, pages 29-31 (2008). x Allison Federici and Jess LaChance, The Guilford Journal of Chemistry, Volume 2, pages 15-16 (2008). vii

viii

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Increased Temperature of Diet Coke and Number of Mentos Increases the Height of Mentos Eruption Anna K The hypothesis of this experiment was, If more mentos are used in an eruption when Diet Coke is at a higher temperature, then the eruption will be higher because there will be more matter being exerted from the bottle with a higher pressure. We completed six trials. These trials included increasing the temperature of the soda while at the same time increasing the number of mentos to see what difference, if any, would occur when these changes are made. 3 of the bottles had 4 mentos used, and 3 different bottles had 6 mentos used. One bottle of each was at a temperature of 298.15 K, one was 301.95 K, and one was 304.15K. The trial which had the results that most supported the hypothesis was the Diet Coke soda bottle which was at a temperature of 304.15 K and 6 mentos used, which had the highest eruption. The trial which least supported the hypothesis was the Diet Coke bottle at a temperature of 298.15 K and 4 mentos used, which had the shortest eruption. The eruption was measured by how high the soda sprayed against the wall. Each brick is equal to 5.5 cm, so the equation for figuring out the height of the eruption is: Number of bricks high × 5.5 = height of eruption. We counted the number of bricks and then used this formula to find the exact height in centimeters. Then we recorded the data and repeated this process for every other trial we had to complete. “The warm diet coke’s results sky-rocketed. Of the two warm test trials, both blast the coke into the air with a large amount of force, resulting in an average height more than double what the room temperature soda achieved.” ¹ This excerpt from the Guilford Journal of Chemistry supports the hypothesis by stating, like the hypothesis, that more force from the heightened temperature increased the height of the eruption. When four mentos were used with a soda temperature of 298.15 K, the eruption reached 440 cm. When four mentos were used with a soda temperature of 301.15 K, the eruption reached 473 cm. And when four mentos were used at 304.14 K, the eruption reached 473 cm as well. We then tested with the same temperatures, but with 6 mentos. When the soda was at a temperature of 298.15 K, the eruption reached 451cm. When the soda was at 301.15 K, the eruption reached 484 cm. And when the soda was at 304.15 K, the eruption reached 495 cm. There was an increase of height of eruption when 6 mentos were used rather than four. For example, at 298.15 K, there was an 11 cm increase. At 301.15 K, there was also an 11 cm increase. And at 304.15 K there was a 22 cm increase. “By the results of the data, it is easily safe to conclude that the warmer the diet coke temperature, the more height the eruption gained.” ² This also corresponds with the data obtained in this experiment, and it agrees with what was found within the data. And it could be concluded that the warmer the diet coke, the higher eruption occurred as well. “Our results clearly support the theory that using warmer Diet Coke will result in a higher Mentos eruption. Each time we raised the temperature of the soda, the result was a taller eruption, with our warmest bottle’s eruption reaching six meters! This can certainly be taken as proof that raising the temperature of Diet Coke affects the eruption size. However, a follow-up experiment where multiple trials are used would be a good idea to test the consistency of this fact” ³ Each time the temperature increased, the eruption increased regardless of how many mentos were used. But a significant increase was observed when 6 mentos were used rather than only 4. Although the data showed a definite conclusion, the data would be more precise and reliable if multiple trials were conducted. In the essay by Tonya Shea Coffey, it stated how Diet Coke heated to a temperature of 320.15 K lost 170 more grams of mass than Diet Coke chilled to a temperature of 279.15 K. 4 The loss of mass signifies the amount of matter exerted from the bottle, which means 15


that a greater eruption occurred when the Diet Coke was at a much higher temperature. “The temperature of the soda greatly affects how much force and height the geyser of soda fizz will shoot up to.” 5 The highest temperature used in the experiment also had much more force resulting in a higher eruption, and it shot up much higher. We placed each Diet Coke bottle into their own separate tub of water heated to specific temperatures (298.15 K, 301.15 K, and 304.15 K). Once at the correct temperatures, they were taken outside and set up against the wall and geyser tubes with either 4 or 6 mentos (depending on which trial) were tightly attached to the nozzle of the soda bottle. The eruptions were promptly set off after the bottles were open to ensure the most amount of pressure would be exerted. Then the height of the eruption was measured by counting the number of bricks high, and then using that along with the formula stated above to find the exact height of the eruption in centimeters. After reviewing the data from the experiment the conclusion is able to be made that the temperature of soda has an effect on the height of a Mentos eruption. As expected, the warmest soda had the highest eruption. [i]In the first 3 trials when we used only 4 Mentos for each different temperature, the heights of the explosions got higher for each trial; as the temperature was higher for each trial. The first trial when the soda was at 298 kelvin the eruption reached 440 cm. On the second trial when the temperature was 3 kelvin higher at 301 kelvin, the eruption reached 473 centimeters which is a great deal higher than the first trial. On the third trial however, when the soda temperature was 304 kelvin the height of the eruption stayed constant at 473 centimeters. However this may be due to error in the experiment, because in our second set of trials the third trial produced a higher eruption of 495 cm than at the second trial at 484 cm. This data is closely related to Justin Husted’s experiment from the Guilford Journal of Chemistry. The room temperature soda in his eruptions had expected results and was a relative increase from the cool soda. The warm diet cokes results sky-rocketed. [ii] When comparing results of this experiment to Justin Husted’s similar experiment, his data suggests the same overall conclusion. The final trial of his experiment was of the warmest soda which was heated in water measured at 308 degrees kelvin. The resulting reaction resulted in an eruption of 300 centimeters which was his highest.[iii] By the results of his experiment it was easy to declare that the temperature of soda does have an effect on Mento eruptions.[iv] Due to a kink in the data I collected, I cannot easily state the same with an equal amount of confidence but, my overall collection of data does suggest it.

[i] Husted, Justin. "Warm Soda Has a Dramatic Effect on the Height of a Mentos Eruption." Guilford Journal of Chemistry 1.1 (2008): 19-20. Print. [ii] Husted, Justin. "Warm Soda Has a Dramatic Effect on the Height of a Mentos Eruption." Guilford Journal of Chemistry 1.1 (2008): 19-20. Print. [iii] Husted, Justin. "Warm Soda Has a Dramatic Effect on the Height of a Mentos Eruption." Guilford Journal of Chemistry 1.1 (2008): 19-20. Print. [iv] Husted, Justin. "Warm Soda Has a Dramatic Effect on the Height of a Mentos Eruption." Guilford Journal of Chemistry 1.1 (2008): 19-20. Print.

16


Two Bottles of Diet Coke Connected to Make One Eruption Will Heighten the Eruption Compared to a Single Eruption Ambur D When two bottles of regular diet coke are connected to cause one eruption, the height of the eruption will be larger compared to a single eruption. When having nine mint mentos added to a single bottle of Diet Coke, the average eruption height will be 433.2cm. When dropping nine mint mentos at the same time to each Diet Coke bottle that is connected to cause one eruption, the average height will be 587.1cm. The Mentos Diet Coke eruption is a famous experiment with high school students. Mentos contain certain ingredients that cause this reaction with Diet Coke, or any soda for this matter. “The numerous small pores on the candy's surface catalyze the release of carbon dioxide (CO2) gas from the soda, resulting in the rapid expulsion of copious amounts of foam.”(Wikipedia) The outer coating the Mentos is important to the cause of an eruption. The small holes the Mentos contains allows the carbon dioxide to squeeze through, getting to the middle. “The potassium benzoate, aspartame, and CO2 gas contained in the Diet Coke, in combination with the gelatin and gum arabic ingredients of the Mentos, all contribute to formation of the foam”(Mythbusters). Gum arabic is a natural gum made of hardened sap taken from two kinds of the acacia tree and gelatin is solid substance, brought from the collagen inside animals' skin and bones. Potassium benzoate is an acid with a low-pH level, lower than 4.5 and aspartame is a noncarbohydrate sweetener used as a substitute for sugar. When all of these ingredients are mixed together with the carbon dioxide in Diet Coke, it causes the instant reaction called a geyser. Gather the supplies to complete this experiment. Attach two elbow shaped PBC plumbing pipes to one “T” shaped PBC plumbing pipe to create an upside-down football goal post or an upside-down digital “Y”. Then use Duct Tape to connect and seal the piping to the Mentos geyser tube provided by Steve Spangler (Educational Toys and Science Toys). Insert nine mint Mentos into each geyser tube carefully. Then slide in the stopper so the Mentos don’t fall out premature to the experiment. Unscrew both tops of the two liter Diet Coke Bottles and insert the geyser tubes in less than thirty seconds, otherwise the carbon dioxide will escape from the bottle. Once each geyser tube is inserted and screwed on the two liter bottles, pull each stopper out of each geyser tube at the exact same time to ensure accurate results. It would be wise to do it against a brick wall, that way counting the bricks first and multiplying that number by 5.7 centimeters is easier than just trying to count the height in centimeters. Create a data table with many trials to ensure accuracy and graph these results. The statement; When two bottles of regular Diet Coke are connected to cause one eruption, the height of the eruption will be larger compared to a single eruption, Proves to be true. Although, there is no mathematical way to explain the height difference between a combined eruption and a single eruption, the height was larger. By doubling the amount of carbon dioxide and other Diet Coke ingredients, while adding them to the doubled amount of ingredients in Mentos, essentially created a larger eruption. To ensure more accurate results it is always wise to do as many trials as possible and apply more duct tape to guarantee no leakage. Endnotes "Diet Coke and Mentos Eruption." Wikipedia, the Free Encyclopedia. Web. 12 Oct. 2011. <http://en.wikipedia.org/wiki/Diet_Coke_and_Mentos_eruption>.

17


"MythBusters: Diet Coke and Mentos Episode Summary - TV.com." TV.com - Free Full Episodes & Clips, Show Info and TV Listings Guide. Web. 12 Oct. 2011. <http://www.tv.com/shows/mythbusters/diet-coke-and-mentos-822481/>. "Geyser Tube." Science Projects Experiments, Educational Toys & Science Toys. Web. 12 Oct. 2011. <http://www.stevespanglerscience.com/product/geyser-tube>.

18


Period 3

The weakening effects of Baking Soda and Sugar on the height of a Mentos in diet coke eruption Catherine D The first time our group performed the experiment we tested how high five Mentos candies would erupt within a bottle of diet coke. We found that the average height at which it erupted was 131.5 cm. We came to this height by counting how many bricks the eruption went up, and measured the length of each brick in centimeters. Upon adding the baking soda and sugar to the diet coke, the eruption was much less impressive, since it hardly erupted higher than the top of the bottle, at about 11 centimeters for sugar and 8 centimeters for baking soda. The reason that it did not go that high was because by the time we got the Mentos into the coke, it had already begun to react. We can determine that the baking soda and sugar were both weakening factors to the eruption of the diet coke. Vinegar didn’t seem to alter the reaction as much, but it did make it go lower. The height of the eruption with vinegar was 76 centimeters. Introduction For our experiment we decided to verify Tonya Coffey’s results and test the effectiveness of adding baking soda to the diet coke. According to Coffey’s results, when she added baking soda to the soda it erupted to a height of 15.5 feet, or 472 centimeters. We also wanted to see how sugar added to the soda would affect the eruption. We came to the conclusion that diet coke does not react as well with sugar or baking soda, because our resulting heights for those experiments were much lower than the control. When adding baking soda and sugar to the diet coke at the same time, we saw that each time, the bottle would overflow without adding any Mentos to it. Experiment 1.

Gather all Materials needed for the experiment

2.

Using a tube that can release objects with the pull of a string, and place five mentos within the tube.

3. Open the diet coke, and as soon as possible place the tube over the coke and drop the mentos in, taking care to tilt the nozzle towards the wall so that the soda leaves a mark that can be measured 4.

Measure how high the soda shot upwards, and record the results; this will be your control

5.

Add 20 ml of vinegar to the soda and then put the nozzle on and repeat the process

6.

Add 20 ml of sugar to the soda and then put the nozzle on and repeat the process

7.

Add 20 ml of baking soda to the soda and then put the nozzle on and repeat the process

8.

Compile the data and graph it

19


Results We found through our experiments that baking soda and vinegar lessened the effects of the diet coke and mentos eruption. Initially when we tested the diet coke it went up 48 bricks, which is equal to 131.5 centimeters. That was the average of three tests we performed. We came to the conclusion that adding sugar would decrease the reaction because when we added it, the soda overflowed before the mentos even entered the soda, which made it go up only 11 centimeters. The addition of baking soda was equally as unsuccessful in increasing the reaction, because it reacted with the soda before the mentos went in and only caused it to erupt 8 centimeters. However when we added vinegar we did get a successful reaction, for the average of the three trials was 27.5 bricks which is 76 centimeters. Conclusion Since the results we found for these additions were harmful to the eruption, we can pretty safely determine that they do not make the coke more open to erupting. We did not think this would be the case, because according to Coffey, baking soda at least should have increased the reaction. According to NASA even, adding a sugary substance to diet coke should create a reaction with the coke, which shows why we did get a small reaction after adding the sugar. A possible reason we did not get strong results for when we just added the baking soda, vinegar, and sugar to the bottle is that there was too wide of a nozzle for the soda to escape from, which made it not go as high. Also the reaction might have started as soon as the sugar was put into the coke, which would have made the mentos less effective. An additional reason the baking soda might have caused the reaction to slow down, is because baking soda is a base which would take away the acidity of coke. Also the amounts of coke and variables used were different then the ones done in other experiments, which must have some impact on the results of the experiment. In the future, other people could place the soda bottle more carefully, or the pull the strings of the gyser more carfully so it doesn’t tip over , make sure that the bottle wasn’t shaken around before performing the experiment, and make sure that you’re using all the same flavor Mento’s for the same trial.

20


Mentos Soaked in Club Soda Prior to Trial Will Cause the Highest Eruption Claire W and Lindsey U

Summary According to the data, soaking Mentos will decrease eruption height from Mentos not soaked in anything, the control of the experiment. However, the highest eruption height came when the Mentos were soaked in club soda for one minute and left to dry for three. The average eruption height in bricks was 16.8 for club soda after three trials were conducted. There was about a 35% decrease from the control eruptions, which had an average eruption height of 26 bricks. Mentos soaked in saliva for a minute, left to dry for three minutes prior to the trial had average eruption height of 14 bricks and a 46% decrease from the control height. Mentos soaked in Diet coke for one minute and left to dry for three minutes had an average eruption height of 8.5 bricks and a 67% decrease from the control height. Mentos soaked in Pepsi for one minute and left to dry for three minutes had an average eruption of height of 6.17 bricks and a 76% decrease in eruption height from the control. Finally the smallest eruption was the result of Mentos soaked in a sugar solution of Splenda and water solution for one minute and left to soak for 3 minutes prior to trial had an average eruption height of 3 bricks and an 88% decrease in height from the control. Overall the additives that the Mentos were 21


soaked in lead to significant decreases in the heights of the eruptions. There was no significant pattern found in the data because it tested additive solutions and not quantitative changes, therefore a mathematical formula to describe these reactions would entail as follows: E=eruption height A= solutions that Mentos were soaked in and M=The Mento itself. So the simple equation is, M+A=E.

Introduction This unique experiment used to measure the height of an eruption soaked in a solution was created based on the results of Tonya Coffey, the professor of the Department of Physics and Astronomy at Appalachian State University. Coffey found that the significance of the ingredients caffeine, potassium benzoate, and aspartame in Diet Coke, and the gum Arabic and gelatin in Mentos which led to a higher eruptionx. In this experiment, many of the solutions used were of different sodas. Just like the findings of Shore and Brownx, Diet Coke did not have the highest eruption, Sprite Zero did. The findings of Musterer and Ruotolox also find that Diet Coke did not have the highest eruption, but Diet Pepsi did. These similar findings show that other solutions other than Diet Coke can have a higher eruption. In another experiment similar to this experiment, by Clark and Agamiex, their control had the highest eruption without any coating. This probably means that soaking a mentos in solutions probably won’t increase the eruption height. According to the findings of Hustedx, the cooler the soda, the smaller the eruption. The results of Husted were also supported by the results of Melillo and Guryanovx, who concluded that the higher the temperature the bottle is heated, the higher the eruption. This probably means keeping the diet coke at room temperature or higher will improve eruption 22


height. In this experiment, it was made sure that the soda was not cooled because of these findings. According to Moalli and Marshx, the ingredients in Mentos like gellan gum and gum Arabic cause a higher eruption because they dissolve, break the surface tension, and makes it so it is less work to expand and form new bubbles. to Moalli and Marshx, the ingredients in Mentos like gellan gum and gum Arabic cause a higher eruption because they dissolve, break the surface tension, and makes it so it is less work to expand and form new bubbles.

Experimental Section This experiment tested the effect of different solutions on Mentos when they were soaked and left to dry before an eruption. Club Soda, Human Saliva, Diet Coke, Pepsi, and a sugar and water solution was tested against a control. First a control was tested three times, where one Mento was dropped into an 8 ounce of diet coke through a geyser and made an eruption against the brick wall. Next, Mentos were dropped into cups filled with half a cup of each solution, and left to soak for approximately one minute. Then they were removed and were left to dry for approximately three minutes, leaving a coat of the specific solution on each Mento. After quickly opening the 8 ounce bottles one of the Mentos was then dropped into the geyser tube where it was then dropped into the Diet Coke to create and eruption which was measured against a brick wall. After three trials with each solution the data was recorded and the average was found, along with the percent decrease in eruption height from the control. Results

23


The Effect Soaking Mentos in Different Solutions has on Height Eruptions

30

Height in Bricks

25

29 25 2426 17.5 1816.8 16 15 14 14 12

20 15 10

Trial 1 11 8.5 8.5 6

5

Trial 2

9.5 7

Trial 3

6.17 3

2

5 1

3

0 Control

Club Soda

Saliva

Diet Coke

Pepsi

Splenda Solution

Solutions that Mentos Were Soaked

% Decrease from Control 100 80 60 40 20 0

67 35

76

88

46

0 % Decrease from Control

24

Average


Conclusion The results of this experiment show how different solutions or additives can deter a Mentos and Diet Coke eruption. It is important to consider the ingredients in each solution that the Mentos were soaked in, and how it directly relates to the results, the idea relates to the idea of Federici and LaChancex that mint Mentos have the highest eruption height because of their flavoring. Club Soda most likely made the highest eruption out of all substance coatings tested because it doesn’t contain sugar, most likely a major factor in why Coke and Mentos react together. This would explain why the Splenda solution had the lowest reaction, because the Mento would be coated with a sugar coating after coating. Therefore the higher the amount of sugar on a Mentos coating directly deters eruption height. Further experiments could entail picking out specific ingredients and soaking Mentos in them other than just picking certain solutions. This would clarify what additives to each substance cause the reaction rather than in this experiment where only the solutions themselves were tested. If conducted with sugary ingredients and non-sugary ingredients this experiment would prove the statement made in the previous paragraph. Experimental Procedure 1. Find a control height (no soaking in any solution) by dropping one Mentos in a 8 oz. Diet Coke bottle 2. Record the height of the eruption 3. Soak 1 Mento in Club Soda (Approximately one minute) 4. Wait for Mento to dry (Approximately three minutes) 5. Drop Mentos in 8 oz. bottle of Diet Coke from geyser 6. Measure height of Eruption (Number of Bricks) 7. Record in data table 8. Repeat process until completing 3 trials 9. Repeat steps 1-5 with saliva, diet coke, pepsi, and splenda solutions

25


How the Size of the Hole in the Nozzle Affects the Height of a Coke and Mentos Eruption Shane G and Clara P

Summary: The objective in this experiment was to see if the holes size in the nozzle would affect just how high the coke would reach when mixed with Mentos. We believed that as the hole got smaller then the coke would shoot higher because more pressure would be forcing the coke out. The pressure would build because the coke would not be able to escape as easily. However, we also believed that once the hole got to a certain point, of being too small, then the geyser would not reach as high because the stream would be too small to give a good push through the air, or because the intense pressure would simply cause the bottle to spray it out, rather than have it stream out, or the bottle would simply explode. (From the findings of previous experiments done and put on Wikipedia (http://en.wikipedia.org/wiki/Soda_and_candy_eruption)) Because of 26


this safety hazard, we were unable to create a hole that small. What we did find, using our four diameter measurements of 2.0 cm, 1.5 cm, 1.0 cm, and 0.5 cm, was that as the hole gets smaller the streams height would increase which proved our original hypothesis. Using two mint Mentos per trial, we found that the average height for the 2.0 cm hole was about 5.25 bricks high which is only 13 % of the largest average. The 0.5 cm hole shot an average of 39.75 bricks high. The 1.5 cm hole shot an average of 13.75 bricks, which is 35 % of the largest, while the 1 cm hole reached an average of 24.75 bricks which is about 62 % of the largest heights average. This proves our original hypothesis that a smaller hole will produce a larger height. Introduction: The Coke and Mentos reaction has been around since the 1980’s but was first widely introduced to the world on the David Letterman show in 1999. Since then there have been numerous videos and records of this type of eruption. In recent years more research has been done and even televised on shows like Time-Warp and Mythbusters. The Guilford Journal of Chemistry has included very conclusive experiments including those by Cutler and Smith who found that the temperature of the Mento can greatly increase the height. We believe that this could have some affect on the nucleation sights on the Mento which are believed to be the true cause of this reaction. We now set out to find our own way to increase the height of the eruption by building pressure in the form of less area for the soda to escape from.

Experimental Section: Materials: 1. Coca-Cola (all the same sized and shaped bottles, with the same amount of liquid.) 2. Drill or some way to cut an accurate and precise hole into the caps 3. A ruler 4. A lot of Mentos (use the same number and kind for each trial – we used two mint per trial) 5. Pencil and Paper for recording data 6. Way of measuring the height (we used the bricks of a wall that the Coca-Cola shot up against) 7. Duct Tape 8. Paper towels or a small cleaning rag Variables and Constants: Independent Variable: Size of the Hole in the Nozzle or Cap Dependent Variable: Height of the Eruption Constants: Since we did the majority of our tests within the same hour a few constants include the temperature of the coke and of the Mentos, the temperature outside, and the amount of wind stayed fairly 27


consistent throughout our time. Others include the type of Mento, the amount of Mentos per drop, the height of the drop, the angle the geyser tilted at, the bottle shape and size, and the amount of soda per bottle. We tried to keep the time between opening the cokes and dropping the Mentos as consistent as we could but there was no real accurate way of telling so I would like to change that next expieriment. Procedure: 1. Cut the holes into the caps, 0.5 cm, 1.0 cm, 1.5 cm, 2 cm diameters. (try to make the holes as clean cut as possible. Note that the geyser tubes original cap is about 1 cm wide and the tube without a cap is about 2 cm wide so the only ones really needed are the 1.5 and the 0.5 cm holes) 2. Wipe inside of geyser so Mentos do not stick with paper towels or a cleaning rag 3. Make sure the 0.5 cm cap is secured to the geyser 4. Flip over and put in two Mentos 5. Insert the key and flip back over 6. Open coke and secure geyser onto the top 7. Set down near a wall or measuring tape and release Mentos 8. Record height 9. Repeat two or three times (depending on supplies) 10. Repeat steps 2-9 for 1.0 cm, 1.5 cm, and 2 cm, diameter holes

Results: Hole Size (Diameter)

Hole Size (Area – cm2)

Trial 1 (Bricks)

Trial 2 (Bricks)

Trial 3 (Bricks)

Trial 4 (Bricks)

Averages (Bricks)

Percents

2 cm

3.142

5

6

5

5

5.25

13%

1.5 cm

1.767

14

13

13

15

13.75

35%

1 cm

0.785

25

24

26

24

24.75

62%

.5 cm

0.196

37

41

39

42

39.75

100%

These numbers show us that the smallest hole gives us the largest height for the stream of coke. The 2 cm diameter hole only reached an average of 5.25 bricks while the half a cm gave us an average of 39.75 28


bricks. The second largest hole had the second smallest height average of 13.75 cm while the second smallest hole had the second largest height average of 24.75. The three larger holes only reached a small percentage of the same height as the smallest hole showing that the smaller the hole is the higher the geyser will reach. (Graph in back) Conclusion: With the numbers previously recorded and discussed slightly we can conclude that as the hole got smaller, the coke would shoot higher because the high amount of pressure would be forcing the coke out in fast, tall upward motion. (Data from Holly Aery and Adam Sierzputowski, found in The Guilford Journal of Chemistry) As the hole size in the cap gets smaller the stream gets higher. This is very important because the original goal of all our experiments was to see how we can achieve the largest coke and Mentos eruption height. Many other tests were conducted by our fellow classmates trying to prove the same thing. They tested ideas such as types of Mentos, amount of Mentos, the height you drop the Mentos from, the temperature of the coke and of the Mentos, and even if there is a different type of drink that will make the eruption higher. We found that when the hole gets smaller the average height of the eruption will grow as well. A hole with a diameter of 2 cm only reached an average of 5.25 bricks off the ground. (We made the eruption next to a wall so we could measure the eruption based off the bricks as shown in the images below.) The second largest hole, 1.5 cm, reached an average height of 13.75 bricks. The third largest at 1 cm made it to an average of 24.75 bricks. Lastly, the smallest hole, with a diameter of only half a cm, reached an average height of 39.75 which is about 161% higher than the 1 cm diameter hole. The reason the smaller hole reached higher is because there is less of an opening for the soda to escape from meaning there will be more pressure forcing it out. However, we believe, due to this fact that if the hole is too small, then the pressure could theoretically become so intense that it would either shoot the cap off or cause the bottle to explode. (As explained in The Nozzle video on Youtube (http://www.youtube.com/watch?v=Q2tAGH2E_Bk) This is why we were unable to go to any size lower than half a cm. We would like to conduct a follow up experiment in a safer location where We can make the hole even smaller to see if it will just spray, form an actual stream, or explode. If this were to happen it would disprove our conclusion showing that there is an optimum sized hole for the maximum height. We would also like to do a follow up experiment on the Cutler and Smith experiment to see if it is instead the difference in temperature between the liquid and Mento.

29


References:

1. "Diet Coke and Mentos Eruption." Wikipedia, The Free Encyclopedia. 2011. October 8th, 2011. http://en.wikipedia.org/wiki/Soda_and_candy_eruption (Used in background and outside information on mentos eruption) 2. Holly Aery and Adam Sierzputowski. The Guilford Journal of Chemistry. Volume 2. Pages 23-26. (2011) (Helped to compare our findings to those of previous research, as well as helping to give data to our conclusion.) 3. "The Diet Coke Nozzle Test." Youtube. June 29th, 2007. Viewed in September-October 2011. (Gave an idea of what to expect, as well what what materials to buy, and helped in formation of hypothesis

30


The height of the Mentos eruption depends on the outside coating Jenna P

Summary: In our experiment, we discovered that the coating on the outside of the Mentos affects the eruption height. We put Mentos with coating and recorded the results however we then took Mentos that were sitting in water for a while and saw the eruption height. There was a drastic difference. With the coating we got results of 16, 21, and 25 bricks. Without the coating we had results of 3, 7 and 9 bricks. We therefore noticed that the coating of the Mentos affects the eruption height.

Introduction: During our experiment we took regular mint Mentos and compared the eruption height to Mentos without the coating on. Our hypothesis was, if we soak the coating off the Mentos then the eruption height would be affected drastically because the coating makes the soda fizz more. Our hypothesis was proven with the results we took. We didn’t tamper with the Mentos for the results of the Mentos with the coating, they were left normal. However, the Mentos with no coating were soaked in water to get all the coating off. To receive the results of the Mentos with coating we put 6 into the geyser and pulled the latch received varied results. We then took the Mentos soaked in water put six in the geyser and pulled the latch the same way we did with the coating and received varied results.

Experimental section: 1. Take 6 coated Mentos out of the package and transfer them into the soda geyser. 2. Take 6 Mentos and put them into a cup of water. 3. Then pull the latch to transport the Mentos in the geyser into the soda. 4. Observe what is going on and the height of the eruption. 5. When the eruption is finished count how high it went by counting the bricks. 6. Repeat steps 1-4 2 more times. 7. Take the Mentos from the water out and transfer then into the soda geyser. 8. Pull latch on geyser. 9. Observe eruption from Mentos without a coating. 10. Record results by counting the bricks to see the height of the eruption. 11. Then repeat 7-10 2 more times.

31


Results: Mentos: With outside coating Without outside coating

First trial 16 bricks 3 bricks

Second trial 21 bricks 9 bricks

Third trial 25 bricks 11 bricks

Our results were varied however all within a range. The Mentos with a coating had results between 15 and 25. Our first trial was the smallest eruption with a coating; it only went the height of 16 bricks. The second trial went the heights of 21 bricks, just a little higher than the first trial and our third and last trial received heights of 25 bricks and was the highest eruption height. Our results without an outside coating of the Mentos varied between 1 and 15 bricks. The first trial without a coating only went the height of 3 bricks and was the lowest eruption height we received. The second trial was 9 bricks and the third and last trials height was 11 bricks high and was the highest eruption height with no outside coating.

Conclusion: In the Mentos eruption experiment our results were clear that the outside coating affects the height of the eruption. We discovered the outside coating is the most important part to a Mentos and soda eruption. We received really high numbers with an outside coating compared to the Mentos without a coating. In other experiments we could find exactly what is causing the eruption and what is in the outside coating making the difference in the height.

32


Diet Coke VS. Energy Drinks Marguerite D and Alex P

Summary: In the lab, “Diet Coke vs. Energy Drinks”, we modified the classic Diet Coke and Mentos Eruption experiment by testing the Diet Coke’s eruption height in comparison to popular energy drinks, Rockstar and Monster. Diet Coke’s results suggested that Diet Coke was in fact better suited for the experiment. Diet Coke had an average eruption height of 13.5 bricks (40.5 inches). Monster came in second place with an average height of 8 bricks (24 inches), while Rockstar trailed behind with an average eruption height of 7.5 bricks (22.5 inches). These measurements resulted in a 57.4% difference between the Diet Coke and the energy drinks. These results did not support our original hypothesis that energy drinks would be better suited for the lab because of their assumed carbonation levels. Introduction: The Mentos Eruption Lab is a classic experiment where different carbonated beverages are examined to see which would produce the highest eruption height when combined with several Mentos. The Diet Coke and Mentos Lab is popular because “it inspires students to wonder and inquiry-driven labs/active-learning demonstrations on this reaction have been implemented.” [1] For the Mentos-Diet Coke reaction, the carbonic acid and carbon dioxide are not products of a chemical reaction but are already present the Diet Coke, whose equilibrium is disrupted by the Mentos. [2] The reaction to the Diet Coke occurs when several Mentos are dropped into the carbonated beverage. Though “numerous theories have been purported to explain the science behind the Mentos eruption”[3], we have come to believe that it’s due to the pressured carbonation being released by the disruption of the Mentos. Some say that “Depending on the number of Mentos dropped into the bottle, the spray height can vary between a few inches and tens of feet”[4]. However, we went in a different direction and made a slight change to the classic experiment by testing the eruption height of energy drinks, Monster and Rockstar. We were looking to prove, like the several unverified explanations of the experiment that have been offered to explain the experiment[5], that energy drinks carbonation would produce a higher eruption height than the original Diet Coke. Materials:  2 cans of Monster Energy Drink  2 cans of Rockstar Energy Drink  2 1L bottles of Diet Coke  3 rolls of Mentos  4 coke bottle nozzles  1 geyser tube  Duct tape 33


Procedure A: 1. 2. 3. 4. 5.

Take Coke bottle nozzle from a Coke bottle Attach geyser tube to the bottle nozzle Use a can opener to remove the top of the energy drinks can completely Use duct tape to securely fasten the Coke bottle nozzle to the top of the can Make sure to do this as fast as you can so you don’t lose too much carbonation

Procedure B: 1. 2. 3. 4. 5. 6.

Dress the Coke bottle up with the geyser tube so it is secure. Fill geyser tube with 4 Mentos. Pull geyser tube string to release the Mentos Back away from the eruption Repeat steps 1-4 and record results For the Monster and Rockstar portion, begin with Procedure A and follow steps 1-5 accordingly.

Data Table: Diet Coke

Monster

Rockstar

Trial 1

13 Bricks

9 Bricks

8 Bricks

Trial 2

14 Bricks

7 Bricks

7 Bricks

Average

13.5 Bricks

8 Bricks

7.5 Bricks

34


Conclusion: After two trials for each beverage, Diet Coke’s average height results of 13.5 bricks trampled the results of Rockstar’s 7.5 and Monster’s 8 bricks. This thoroughly disproved our hypothesis of the Energy Drinks having a higher success height than Diet Coke because of their carbonation levels. The failure of the Energy Drinks could be attributed to the fact that the cans release the majority of the carbonation. Something to attempt the prevention of this in the future would be to modify the top of the can so you can fit the Mentos in without completely removing the top. This might preserve the carbonation enough to get past only a few inches.

[1]

Diet Coke and Mentos: What is really behind this physical reaction?, Dr. Tonya Shea Coffey, page 1

[2]

Diet Coke and Mentos: What is really behind this physical reaction?, Dr. Tonya Shea Coffey, page 2

For an informative historical account of the Mentos Eruption, Steve Spangler’s website is recommended: http://www.stevespanglerscience.com/experiment/00000109 [3]

[4]

Diet Coke and Mentos: What is really behind this physical reaction?, Dr. Tonya Shea Coffey, page 1

[5]

Mass literature on the Mentos Eruption cites the website of Fred Senese

35


Period 4 Crushing Mentos will not make the eruption larger. Sara D and Alexa B

Summary: In our experiment, we crushed eight mint mentos and put four into two liter diet coke bottles. Then we put four non-crushed mentos into two liter diet coke bottles. As a result not crushing the mentos allows the eruption to be larger. Each brick had the height of 2.25 inches. Therefore when the mentos were crushed the first measurement was 78 inches. The second measurement was 72 inches. The height difference was six inches. Having the mentos not crushed during the third experiment had a height of 155 inches. The last experiment had a height of 157 inches. The difference between the heights was 2 inches. The difference between the crushed and non-crushed was 2%.

Introduction: It is said that the theory behind what makes the diet coke erupt is that there is an acid-base reaction because Coke is acidic.1 Some people tried to make an experiment to increase height. The world record is 30 feet and nobody has yet to make it. By trying to get more height people changed the soda type. As it turns out, the diet coke had the highest eruption. 2 What we did was to see if crushing the mentos would affect the height. We were incorrect, keeping the mentos how they are leads to a larger eruption.

Experimental Section: For this experiment we gathered all of our materials that include four two-litter diet coke bottles, sixteen mint mentos, and the device to launch the mentos. After, we set everything up, meaning placing the mentos into the tube then releasing the string. Once the coke erupted we calculated the results.

Crushed mentos

2m

1.8 m

Non crushed mentos

4m

3.9 m

Conclusion: After doing this experiment we found out that not crushing mentos allows the eruption to be higher. We know this because with the crushed mentos the average height was 75 inches. Having the mentos not crushed, the average height was 156 inches. We suggest that maybe after this experiment you can use more mentos (crushed and non-crushed) to increase the height. The reliability of our data is pretty high with some errors. All of our materials were constant and we used the same amount for everything. Though, some errors did occur. We opened the bottle a little early which released some carbon dioxide. Also the bottles could have been shaken. Procedure: 1. 2. 3. 4. 5. 6.

Gather materials: 4 two litter diet coke bottles, sixteen mentos, devices for eruption Set up materials Place 4 crushed mentos into the device Pull the string Count the number of bricks that the eruption hit Repeat steps 3-5 with crushed mentos 36


7. Repeat steps 3-5 without crushed mentos 2 times

References: 1

Reasoning for eruption- http://www.newscientist.com/article/dn14114-science-of-mentosdiet-coke-explosionsexplained.html

2

Angelise Musterer & Lindsay Ruotolo. Guilford Journal of Chemistry, Vol. 2, pages 1-2 (2009).

3. Guilford Journal of Chemistry, Vol. One, Page 5. (2008)

Www.rimmkaufman/rkgblog/2007/12/21/steve-spangler)

4.http://tnst.randolphcollege.edu/apply10/inst_mats/handouts/EnvSc/Coffey08_diet_coke_and_mentos.pdf

5. http://www.sciencebuddies.org/science-fair-projects/project_ideas/MatlSci_p023.shtml

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Mentos Car Eruption Andrew T and Mark L

We discovered that when you put regular Pepsi on a car and put mentos in the tube it make the car move 3 feet from the curb. On the other hand when you put diet Pepsi with caffeine and put mentos in the tube the car only moves 2cm from the curb. After doing three trials of both sodas the number came out similar. The trick is to angle the soda up so the mentos can fall into the soda to cause the eruption. The car didn’t go for a long time it was more of a sprint it seemed like to me.

Procedure: Trial one Pepsi- 3 feet Trial one diet Pepsi- 2 cm Trial two Pepsi- 2.5 feet Trial two diet Pepsi- 1cm Trial three Pepsi- 1 foot Trial three diet Pepsi- didn’t move Something that Mark and I should have done was made it easier for the Mentos to fall into the soda because some of them would fall in but not all of them witch caused false information. 38


That picture above was of the last trial of the diet Pepsi. As you can see something went wrong and the soda started spraying all over the pavement. If I were to do this experiment again I would change a lot of things. First id get an r.c. car and the body off it and tape a two-liter bottle of coke and see what happens. I believe using more soda would make the car go longer and farther. I would suggest this experiment to a lot of people because it’s fun, keeps you entertained, and you can see how high you can get the soda to go. Also playing with mentos and soda is just fun.

39


Period Five

Drilling Holes in Mentos Will Increase Eruption Height Ben E

Summary The famous Diet Coke and Mentos eruption occurs when Mentos candy is dropped into a freshly opened bottle of Diet Coke, resulting in the famous eruption. Many factors are hypothesized to be behind the reaction, one of which is that the Mentos’s relatively rugged surface provides “nucleation sites” where CO2 bubbles form. Apart from only one accepted article by Professor Tonya Coffey, the study of Agamie and Clark which is printed in the Guilford Journal of Chemistry, and an episode of Mythbusters, there is currently little or no information on this subject. This experiment was conducted to see first-hand how surface area can affect eruption height, including the effect of using “donutMentos,” or Mentos with a hole drilled into the middle. Introduction The experiment was conducted to see how affecting the surface area of Mentos candy would affect the height of the eruption. Smoothed, roughed, normal donut, and smoothed donut Mentos were dropped into 2-liter bottles of Diet Coke. Due to problems with time, the trial involving roughed donut Mentos could not be executed. Experimental Procedure Materials that were used in the experiment include a six-roll pack of Mint Mentos candy, with 20 candies per roll, a sixpack of 2-liter Diet Coke, sandpaper for smoothing and roughing up the Mentos, a screwdriver for working holes into the Mentos, toothpicks for poking holes into the Mentos, and a Spangler’s Geyser Tube for releasing the Mentos and for directing the spray. The experiment was taken against a brick wall with an identifiable white silicone line around 54 bricks off the launch site. Each brick, plus the extra space taken by the mortar, measured 7.35 cm. The independent variable was the affect applied to the surface of the Mentos. The dependent variable was the height of the eruption. The control was un-tampered-with Mentos. Constants were the type of Mentos used (Mint), type of soda and quantity of soda used (2-liter Diet Coke), the temperature of the Mentos and the Diet Coke, and the launch site. Only one trial of each independent variable was done, due to lack of supplies. The procedure is as follows: 1. First, the Mentos has to be prepared according to the trial. Smoothed Mentos were rubbed on sandpaper for about 15 seconds on each side, while roughed Mentos were struck sharply across the sandpaper three times on each side. To make donut Mentos, a screwdriver was used to drill a small pit into each side of a Mentos, and then a toothpick was pushed through one of the pits, coming out the other side and forming a hole. Holes were formed in the Mentos before anything else was done to the surface. Ideally, the Mentos would be frozen at this point, but in this experiment, they were not. 2. The next step is to slip the Mentos into the Geyser Tube. Make sure the pin used to keep the Mentos from falling through prematurely is in place. Put eight of the current trial in the Geyser Tube. DO NOT open the bottle of Diet Coke yet. 3. Place the Diet Coke (unopened!) in the launch site. In this case, the bottle should be placed 15 cm away from the brick wall. Make sure the bottle is exactly upright; it cannot be tilting, or the launch height will be compromised. Make sure that the bottle is not shaken before or now. If it was shaken, it is recommended that the launch be put off at least 16 sec, for the soda to settle down. 4. Now is when the bottle is opened and the Geyser Tube goes on. Be aware, the moment the bottle is opened, the eruption begins to lose its potency because CO2 begins to escape from the open nozzle. Therefore, try to 40


minimize the time spent between the moment the bottle is opened and the launch; preferably about 10 sec. Make sure the Geyser Tube in on securely. 5. Once the Tube is on, stand back, count to three, pull the pin, and run. 6. After admiring the eruption, measure how high the eruption went. In this experiment, bricks were counted to gauge how high the spray flew. Then take off the Geyser Tube, toast to the successful launch, eat a Mentos, and repeat for another trial. Results The lowest of the eruption heights was achieved by the smooth Mentos, which reached a height of 46 bricks, or 352.8 cm. Next in the highest was the roughed Mentos, for despite tipping towards the wall, managed to reach up to 49 bricks, or 374.9 cm. Both the normal and the smoothed donut Mentos reached 59 bricks, or 433.7 cm, tying the two trials for the highest eruption height. The roughed donut Mentos trial was skipped, due to lack of time. The control trial, the normal Mentos, reached 51 bricks, or 389.6 cm. A graph for the data is available later in the report. Conclusion and Discussion Taking all of this data, it can be concluded that increasing the surface area of the Mentos will increase the height of the eruption, especially if a hole is poked through the middle of it. The smoothed, non-donut Mentos had the lowest eruption height of the trials at 352.8 cm, and the donut Mentos, both normal and smoothed, had the highest at 433.7 cm. It verifies the hypothesis that increasing the surface area of Mentos candies before dropping them into Diet Coke will increase the eruption height. It also correlates with the data from two other studies, Professor Coffey’s and Agamie and Clark’s. Coffey’s experiment was taken to test a whole slew of hypotheses about the Mentos eruption, one of which was how surface area affects the length of the eruption. They comfirmed that altering the roughness of the surface of the Mentos will increase the explosiveness of the reaction. Agamie and Clark’s study tested the effect of removing the coating on Mentos versus dipping them in dishwashing fluid on the height of the eruption. They found that they were both were surpassed by the control, which was normal Mentos. This is not surprising; removing the coating from the Mentos will essentially make the surface of the Mentos smoother, while dipping Mentos in dish soap will fill the nucleation sites present on the candies. Another study that can be pointed out is that of Marsh and Moalli, who tested the effect of applying different coatings on Mentos. However, since the dependant variable was the length in time of the reaction and not the height of the eruption, it has little significance to this study. Be aware that during the trial for roughed, non-donut Mentos, the bottle tipped, bringing the spray to bear against the brick wall. This caused the eruption height to go down, putting it below the control’s. Also, the trial for roughed, donut Mentos could not be executed, due to a lack of time. It would be worthwhile to come back and do a trial testing it. Overall, despite a couple of discrepancies, this study’s results matches those found by two others, and concludes that affecting the surface area of Mentos candy will increase the height of the spray.

41


The Graph: 450 430 410 390 370 350

330 310 290 270 250

Control

Smooth

Rough

Donut

Smooth Donut

Roughed Donut (N/A)

P.S. Due to some technical difficulties, it was not possible to label either axis. The x axis is the affect applied to the surface of the Mentos, while the y axis is the eruption height, in centimeters.

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The Effect of the Height of Introduction of the Mentos into the Diet Coke on the Severity of the Reaction Dan F and Samuel W

Summary In our experiment, we attempted to adjust the entry level of the Mentos into a 1 liter Diet Coke bottle. Unfortunately, we were unable to get viable results because of faulty engineering. Introduction In an experiment that appeared in the paper “Diet Coke and Mentos, What Is Really Behind This Physical Reaction?�(End Notes, 4) a group undergraduates at Appalaichan State University, gum arabic was introduced at different heights as to see what effect it had on the eruption height. Releasing the gum arabic at a lower height on the bottle had a positive effect on the reaction, as shown by a higher eruption height (1). This is due to the carbon dioxide bubbles in the bottle having more exposure time to the reaction (2). This was also reflected by another experiment where crushed Mentos were compared with unmodified ones (3). The crushed Mentos were less effective because they took longer to reach the bottom and the majority of the reaction happened while the Mentos particles were falling. Experimental Section (Procedure) Materials: -1 unmodified 1l bottle (control) -1 bottle with a hole drilled at 10 cm from the bottom (1st mod) -1 bottle with a hole drilled 5 cm from the bottom (2nd mod) -1 modified syringe (5) -duct tape -wax paper -2 rubber bands -6 liters of Diet Coke -Ten rolls of Fruit Mentos Step 1: Insert Mentos into modified syringe, put wax paper Step 2: Pour soda into 1 liter bottle Step 3: push 4 Mentos into bottle Step 4: Measure height of the eruption Step 5: repeat steps 1 through 4 with the 2nd modified syringe, the one with the hole cut 5 cm from the bottom Results No valid data was collected as a result of faulty engineering. Conclusion In the experiment, it proved impossible to gather data as result of engineering flaws along with a few other mistakes. The seal between the syringe and the bottle failed to stay watertight, causing a loss of internal 43


pressure, and possibly caused a smaller eruption. A loss of carbonation also occurred when the Diet Coke was transferred from its original container to the testing bottle. A solution to these errors is to introduce the Mentos through a long tube placed through the top of the original bottle of Diet Coke, instead of pouring it into a modified one. Here is a materials list and procedure for this possible second experiment based upon this idea (There is also a diagram attached to the back): Materials: 1. PVC pipe, smaller in diameter than the neck of the bottle 2. Cut at lengths of 10 cm and 15 cm. 3. Copper wire 4. 3 2l bottle of Diet Coke 5. Duct tape (6) 6. Wax paper 7. Rubber bands Procedure: 1. For control, put Mentos in through the top, measure height 2. Put Mentos in 5 cm tube, seal at one end with rubber bands, wax paper 3. Put tube into top of the bottle, seal with duct tape 4. Push mentos through wax paper with copper wire 5. Record eruption height 6. Repeat with 10 cm tube End Notes Coffey, “Diet Coke and Mentos, What is really behind this physical reaction?” pg 555 Coffey, “Diet Coke and Mentos, What is really behind this Physical reation” pg 555 Coffey, “Diet Coke and Mentos, What is really behind this Physical reation” Pg 556 Coffey’s paper was an investigation into the now popular Diet Coke and Mentos experiment. She and a group of undergraduates tested different aspects of the reaction, like changing the surface area using different ingredients, and introducing the Mentos in different ways. 5. The modified syringe we used had the top sawed off so the Mentos could be pushed in using the plunger. 6. An alternative to the duct tape, and probably a more effective mode of sealing the tube would be to use something like the screw top on the Geyser Tube. 1. 2. 3. 4.

44


Smaller Nozzle Size Creates Larger Spray during the Eruptions

Mentos

Evan H. and Michel I.

Summary: For our experiment, we covered a soda bottle with a geyser tube with three different covers to see the effects on the eruption caused by combining Mentos and diet coke. The covers that we used were a geyser tube with 1) a cap (1.5 cm opening), 2) a coke bottle cap with a hole (1 cm opening) and 3) a garden hose nozzle (0.5 cm opening). In so doing, we were able to see if a smaller nozzle size created a larger spray during a Mentos and diet coke eruption. The geyser tube with the coke bottle cap with a 1 cm hole created the highest eruption measurement of 396 and 401 cm. The geyser tube with the 1.5 cm hole in the cap created an eruption reaching 340 and 314 cm. The geyser tube with 0.5 cm hole garden hose nozzle created the lowest eruption height of 152 and 290 cm. Introduction: A liquid eruption can be created by increasing the pressure within a fluid held in a closed space. During a Mentos and Diet Coke experiment, Mentos mint tablets are introduced into a bottle of Diet Coke or Pepsi. The resulting reaction is a stream of soda, which is guided through the neck of the bottle. The reaction within the bottle is due to a rapid release of carbon dioxide bubbles. In its simplest form, the Mentos and diet coke experiment usually involves dropping Mentos mints into diet coke, resulting in a foamy eruption, which can often be several meters in height.š When the two elements combine, they result in a massive increase of carbon dioxide pressure released from the Diet Coke. It expands the liquid and forces it out the top of the bottle.² In the past there have been many theories to explain the science behind the Mentos Eruption. The first widely viewed Mentos eruption occurred on the David Letterman show on September 14, 1999 3. In terms of scientific research this field is still in its still a fairly unproven area. There have been numerous videos and TV shows documenting eruptions. One of the most well-known documented experiments is on the set of the TV program Mythbusteres 4.

45


Experiment: In this experiment, three nozzles of different size (0.5cm, 1 cm and 1.5 cm) were individually put onto a release mechanism called a geyser tube. The geyser tube was then loaded with a Mentos tablet, held in place by a pin, so that the Mentos tablet was held inside the geyser tube. The loaded geyser tube was then placed over a 1 liter bottle of Diet Coke. The pin was pulled, allowing the Mentos tablet to enter the bottle of Diet Coke. The emitted stream of liquid was measured for height. Each nozzle setup was sampled twice.

Graph 1

450 400 350

Height of 300 eruption 250 stream(cm) 200

Trial 1 Trial 2

150 100 50 0 Bottle cap w/ hole (1 cm)

Geyser Tube w/ cap (1.5 Nozzle cm) Type

Garden Hose Nozzle (0.5 cm)

Results:

Table 1

Nozzle

Height of stream (cm)

Bottle cap w/ hole Geyser Tube w/ cap Garden Hose Nozzle

Trial 1

Trial 2

396 340 152

401 314 290

Conclusion: During the Diet Coke and Mentos experiment, the different sized nozzles over the geyser tube proved to be the difference in average eruption height. As seen in the Graph 1 and Table 1, the smaller the nozzle width the higher the mentos eruption. This is up until the hole gets too small, at around 0.5 cm, as shown with the garden hose nozzle. These results most likely occurred due to the increase in eruption pressure from the soda. For example, if one was to spray an open hose, it generally does not go very far. But, when you use a thumb to close off part of the hose exit, the water accelerates and goes farther. Some errors that could have been present during the experiment were 1) a variable in the time it took to secure the geyser 46


tube on each coke bottle which allowed CO2 to release from the Diet Coke and 2) an imperfect nozzle fit, which allowed pressure to leak around the nozzle. Also, the nozzles could have been angled, changing the height of the eruption. One follow-up experiment could be to increase the number of width gradations (1, 0.85, 0.75, 0.65 and 0.5), in order to determine the point at which the nozzle width hinders the height of the eruption. The significance of these results shows that a smaller the nozzle width will cause a higher eruption when conducting a Diet Coke and Mentos eruption. Experiment Procedure: Gather materials: 10 one liter bottle of Diet Coke, 2 packages of mint Mentos, and a piece of ply wood (1 foot by 6 inches), one Mentos experiment plastic geyser tube with cap, measuring tape, water balloon hose nozzle, bottle cap with 1 cm opening Step 1: Extend the measuring tape vertically up the wall about 20 ft. Step 2: Put 2 Mentos mints in the geyser tube with the pin securely in place with the original cap of top of the tube. Step 3: Set up your experiment area by laying the piece of plywood down, next to a wall, near the measuring tape. Step 4: Place the closed bottle of diet coke on the ply wood, angled slightly at the wall. Step 5: Quickly unscrew the cap of the diet coke bottle, place the geyser tube in the top of the bottle and screw it onto the bottle. Step 6: Pull the cord attached to the pine, making sure it doesn’t tip the bottle, and run to a safe distance. Step 7: Record the eruption height on the wall, in comparison with the measuring tape Step 8: Repeat steps 2-7 once more. Step 9: Place the garden hose nozzle on top of the geyser tube and duct tape it on to ensure there is no pressure leakage Step 10: Repeat steps 2-8 with the garden hose nozzle Step 11: Place one of the coke bottle caps on a flat working environment Step 12: Hammer the nail into the center of the cap Step 13: Replace the top of the geyser tube with the bottle cap Step 14: Repeat steps 2-8 with the improved geyser tube End Notes: 1. Dr. H. Brielmann, The Guilford Journal of Chemistry. Volume 1, Page 1 (2007) 2. Tonya Shea Coffey, Diet coke and Mentos what’s early behind the physical reaction. Page 551 (2008) 3. The original Letterman Show Mentos Eruption may be viewed on the internet 4.

(http://www.chem.uic.edu/marek/letterman0/video/mentos.htm.) The original mythbusters investigation of the mentos eruption may be found online at (http://dsc.discovery.com/videos/mythbusters-diet-coke-and-mentos.html).

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High Surface Area increases a Coke Mentos Eruption Height Grace I and Amanda M

Summary: An increase in the surface area of a Mentos also increases the eruption height. According to the paper "Diet Coke and Mentos: What is really behind this physical reaction?" Tonya Coffey also agrees with this statement.1(551) When conducting the experiment, the data shows that when a Mentos was scratched on both of its sides the height of the coke and Mentos eruption increased compared to when the Mentos was left smooth or only scratched on one side. In fact, the Mentos eruption increased by 30% when the Mentos was scratched on both sides. However, our data did show that when the Mentos was scratched on only one side the eruption height was less, by one-third of an inch, then the eruption height of a smooth Mentos. This decrease may just be experimental error and if conducting the experiment again should be retested. Introduction: Coke and Mentos is a famous experiment where Mentos are dropped into a bottle of coke and the soda erupts. In our studies we tested to see how surface area effects the explosion. Other studies have been conducted and have also hypothesized that a rough surface of the Mentos can help break the strong polar attraction that water molecules have for each other by providing growth sites for the carbon dioxide.2(551) Our data conveyed the results that our hypothesis as well as the hypothesis in Tonya Coffey's paper are correct.3 (557) Increased surface roughness implies a higher surface area to volume ratio, meaning that more growth sites should be present on per unit volume.4 (556) In fact, surface roughness may be one of the most important causes of the eruption. 5 (556) Mentos with a lower surface area result in a smaller eruption. 6 (556) Tonya Coffey also tested different items other than Mentos to drop into the coke.7 (553) She found that Wint-O-Green Lifesavers, which had root-mean-square roughness of 2630, created the highest eruption compared to mint Mentos, fruit Mentos, and rock salt.8 (553) The Wint-o-Green Lifesavers have a rms roughness that is more than a factor of 10 larger than the rms roughness of the rock salt.9 (556) The Lifesaver reaction had the largest eruption spray.10 (556) Experimental: In this experiment, Mentos with different surface areas are dropped into 12 oz. bottles of coke. To do this experiment, you have to gather all materials: 9 bottles of coke, 9 Mentos, a geyser tube, a measuring tape, and a paper clip. Then, 3 of the Mentos have to be scratched with the paper clip, on one side and 3 of the Mentos have to be scratched on both sides. The remaining 3 Mentos will be left smooth on both sides. Put one of the smooth Mentos into the geyser tube and drop the Mento into coke bottle. Measure the height and record the data. Then do the same steps with the one side scratched Mentos, and the both side-scratched Mentos. Do 2 more trials for each surface area and record the data.

48


Mentos surface area Trial 1 Trial 2 Trial 3

Smooth

One side scratched 51 51 64

Trial 3 height 56 46 67

Average 41 49 48 48 79 70

Results: In this experiment, we tested how the surface area of the Mentos would react differently to coke. There wasn’t a significant difference between one side scratched eruption height and the smooth Mentos eruption height. The one side scratched Mentos average eruption height was 48 cm and the average eruption height was 49 cm. Although, there was a significant difference between the both sides scratched Mentos and the other two Mentos. The average eruption height of the both sides scratched Mentos was 70 cm or a 21 cm difference in height. The results were not always consistent. For example, the second trial for the smooth Mentos was 56 cm while the third trial was 41 cm. Some of the results were consistent, though. For example, the first trial height of the one side scratched was 51 cm, the second trial height was 46 cm and the third trial height was 48 cm, which were all relatively close in height. The two sides scratched Mentos were not that consistent either because the first trial eruption height was 64 cm or the second trial height was 79 cm. Conclusion: It was hypothesized that different amounts of surface area on Mentos would change the eruption height when the Mentos were dropped into coke. The hypothesis was proven correct, but only slightly. In the results section 49


it said that there was not a significant difference between the smooth Mentos, and the one side scratched Mentos eruption heights but there was a big jump in eruption height between those two and the both sides scratched Mentos. A scratched surface area on a Mentos makes the eruption height taller because the growth sites of the bubbles are already exposed. The reason for the smooth Mentos and the one side scratched Mentos having similar eruption heights was that the time it took for the coating to come off one the smooth Mentos was not that different from the amount of time the coating took to come off of the one side scratched Mentos. For the two sides scratched Mentos, though, the eruption was immediate because it barely had any coating on its surface which meant that there would be more carbon left in the coke to make a larger eruption. The surface area has to be completely scratched to make a significant difference in eruption height. It also stated in the results section that the data of the smooth and both sides scratched Mentos was inconsistent while the data for the one side scratched Mentos was consistent. It was predicted that the both sides scratched and the one-side scratched Mentos would have the inconsistent results because each Mento wouldn’t have been scratched the exact same amount. It was also predicted that the smooth Mentos would have very consistent data because they have the exact same amount of surface area. I believe that the results turned out the way they did due to errors in the experiment. One error was that some bottles of coke make have been shaken a little bit due to the process of taking the cap off, and putting the geyser tube on which leads to the other error. The other error that could have occurred was the amount of time in between taking the cap off of the bottle and dropping the Mentos into the coke bottle. The more time it took to get the mento into the bottle of coke, the more carbon was released from the bottle which meant that the reaction would be smaller. Changes I would make to this experiment if it were retested would be the amount of trials because some trials more have had error and that would affect the data. More trials would give a more precise and accurate reading of the eruption height of Mentos with different surface areas. In conclusion, high surface area of Mentos increases a Mentos eruption height. Endnotes: 1. Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 551 (2007) 2. Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 551 (2007) 3. Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 557 (2007) 4. Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 556 (2007) 5. Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 556 (2007) 6. Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 556 (2007) 7. Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 553 (2007) 8. Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 553 (2007) 9. Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 556 (2007) 10. Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 556 (2007)

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The Amount of Time between Opening a Bottle of Diet Coke and the Mentos Release Affects the Size of the Eruption Olivia S and Bronwyn R Summary This experiment tested the effect of the amount of time between opening a bottle of Diet Coke and the release of Mentos into the coke on the height of a Diet Coke-Menots eruption. It was hypothesized that if the amount of time between the opening of the Diet Coke and the Mentos release is increased, then the eruption will be smaller because there will be less carbon dioxide. To test this hypothesis, there where three different amounts of time used, thirty seconds, one minute and five minutes. There were two trials for each time tested. The average height of the eruption after thirty seconds was 60. 5 bricks (332.75 cm), after one minute was 52 bricks (286 cm), and after 5 minutes was 47 bricks (258.5 cm). Introduction This experiment came into the public eye after it was used on the David Letterman show in 1999 and after it was a subject on the show Mythbusters in 2006.x Since then, the experiment has become a popular science experiment in elementary to college level classrooms.x In its simplest form, the Diet Coke-Mentos explosion experiment is dropping fresh Mentos into a newly opened bottle of Diet Coke, creating an eruption that can range from a couple of inches to the world record of 29.2 feetx, depending on the number of Mentos placed in the soda.x The basic ingredients that cause this reaction are gum arabic and gelatin in the Mentos as well as the caffeine, potassium benzoate, and aspartame in the Diet Coke.x The carbonation in the soda also has an effect on the height of the eruption.x In this experiment, Diet Coke is used because it contains aspartame and caffeine, two crucial ingredients to the success of the explosion.x Mint Mentos were also used because they do not have an outer coating, like many other flavors of Mentos. This allows more CO2 bubbles to form on the candy, resulting in a bigger reaction.x

Materials Six bottles of Diet Coke Twelve mint Mentos One geyser tube One stopwatch A pair of safety goggles Tape measure (optional) Procedure 1. Place two Mentos inside the geyser tube 2. Put on safety goggles 3. Set coke bottle on the ground, next to a wall, and at an angle so that when an eruption occurs, the coke can hit the wall, making it easier to measure the height of the eruption. 4. Simultaneously open the coke bottle and start the stop watch 5. Screw the geyser tube onto the opening of the coke bottle- DO NOT release the Mentos 6. When the stopwatch reaches thirty seconds, release the Mentos and stand back from the coke bottle. 7. After the eruption has stopped measure up to the highest point of the eruption (which should be where the coke hit the wall) by counting the number of bricks it reached to, or using a tape measure. 8. Record the height of the eruption. Repeat this trial. 9. Repeat steps 1-8 replacing thirty seconds with one minute, then five minutes. 51


Results Our experiment tested the explosion height of the Diet Coke after different lengths of time from the opening of the bottle. On the whole, the longer the bottle had been kept open, the shorter the height of the explosion. For example, when the Mentos were dropped in 30 seconds after opening the bottle, the average eruption height was 60.5 bricks (332.75 cm), in comparison to the average of the 5 minute trial, where the average eruption was 47 bricks (258.5 cm). Time from Bottle Opening to Mentos Drop 30 seconds 60 seconds 300 seconds

Trial 1

Trial 2

Average

61 bricks (335.5cm) 52 bricks (286 cm) 47 bricks (258.5 cm)

60 bricks (330 cm) 52 bricks (286 cm) 47 bricks (258.5 cm)

60.5 bricks (332.75) 52 bricks (286 cm) 47 bricks (258.5 cm)

Time of Carbonation Release Vs. Eruption Height 400

350

Eruption Height (cm)

300

250 Trial 1 Trial 2 Average

200

150

100

50

0 30

60

300

Time (seconds)

Conclusion This experiment examined the effect of the amount of time between opening of the Diet Coke bottle and the Mentos release. The data collected strongly supports the theory that the more time elapses between the opening of the bottle and the release of the Mentos, the less explosive the reaction will be. This is most likely the case because the longer the bottle is opened prior to the reaction, the more time carbonation (which might be a catalyst in the reaction) has time to escape.x Because the carbonation is significantly decreased, the reaction yields a shorter spray height. A follow-up experiment might be to compare sodas with different expiration dates, as the ones with nearest expiration dates will have sat on shelves longer and most likely be flatter (less carbonated). Another follow-up experiment could be 52


to buy a set of sodas with the same expiration date and perform the experiment at different times in relation to the expiration date; for example, one could be set off one month prior to the expiration date, another on the date, and a third one month later. x

Professor Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 551 (2008). x Professor Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 551 (2008). x Dr. H Brielmann, Guilford Journal of Chemistry: Introduction to the First Issue of the Guilford Journal of Chemistry, Page 4 (2008). x Professor Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 551 (2008). x Professor Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 551 (2008). x Carly Clark and Jenn Agamie, The Guilford Journal of Chemistry Volume I: How the Coatings of Mentos Affects the Size of the Mentos Eruption, Page 17 (2008). x Professor Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 551 (2008). x Professor Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 554 (2008). x Professor Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 552 (2008).

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Fruit Mentos Caused the Largest Explosion as Opposed to Strawberry and Green Apple Mentos Ashely Z and Katie N

Summary Coffey’s results support that the fruit Mentos created a larger explosion because their coating dissolves more easily in water.1 she also states that the mint Mentos went just as high as the fruit ones, but we did not test the mint Mentos. Although Both Coffey’s and our data support that the fruit Mentos cause the highest eruption, the Mythbusters data conflicts. They added their own waxy coating which covered the rough patches that would have otherwise been exposed.2 According to professor Coffey, Aspartame that is found in diet drinks is more explosive3, which is why we used diet coke in our experiment. We also used Diet Coke because it has more aspartame than the preservative potassium benzoate, which prevents the eruption from going higher.4 we tied our Mentos together so they would sink to the bottom faster. Tonya Coffey’s study previously proved that the farther the bubbles have to travel through the liquid, the higher the explosion will go5. This may be why that in Coffey’s experiments the crushed Mentos did not go as far, which is why we chose to keep them whole. She also states that there is not always a direct relation in the distance traveled through the liquid, shown by her test with the molecular sieve beads6. The fact that we put holes through the center of our Mentos may have also contributed because more of the rough surface was exposed, which is one of the most important causes of the diet coke reaction.7 Coffey also found that the hotter beverages cause a higher eruption, so we didn’t refrigerate ours and kept them at room temperature.8 54


Introduction One of the most well-known experiments for science classes is the easy experiment of Mentos and Coke. In this experiment, the height of the eruption was tested to see if different types of Mentos were effective and if tying the Mentos together would help weigh them down to produce a bigger eruption with the different Mentos. Fruit Mentos and Diet Coke were used because in Tonya Coffey’s article, she discovered that the fruit Mentos and Diet Coke were the most efficient in producing the highest eruption.9 the result of the experiment was that the fruit Mentos produced the highest eruption.

Experimental Section 1. Gather the required materials (Please see below). 2. Take 6 fruit Mentos and make a hole in the center of each of them using the specified nail. Then take the spool of thread and cut a thin piece of thread and string the 6 fruit Mentos together to make the Mentos fall to the bottom quickly. 3. Place 1 of the bottles of coke near the brick wall at a slight angle for measuring later and make sure that the bottle REMAINS CLOSED! 4. Very quickly, open the bottle, place geyser tube on top, and place Mentos in tube. Pull string out of the geyser tube to release Mentos and step away to prevent being sprayed. 5. Measure the height of the eruption based on the height of wetness of the wall. Either count the amount of bricks if using a brick wall and multiply that number by the length of the brick or use a long measuring tape and measure the height. Record data in cm. 6. Repeat once using fruit Mentos. Then repeat twice for each type of Mento using strawberry and green apple Mentos. Make sure that for each Mento type, there are 2 trials. Materials: 12 fruit Mentos, 12 green apple Mentos, 12 strawberry Mentos, a 2-inch 4-d (penny) nail, a spool of fine thread, pencil/pen, graph for recording data, 6 1L-bottles of diet coke, geyser tube, brick wall or hard surface to measure eruption height, measuring tape, and scissors to cut thread. Results The first trial that was performed was the first trial of the fruit Mentos. The eruption height of this was 198 cm which was the highest eruption and most spectacular recorded in this experiment. The second trial of fruit Mentos reached 181.5 cm. Next the green apple Mentos were tested and these produced very small wimpy eruptions compared to the fruit and strawberry Mentos. The first trial was 121 cm and the second trial was 154 cm. There may have been a minor error in the first trial due to the geyser tube (For more, please refer to the conclusion). The last set of trials was the strawberry Mentos. The strawberry Mentos landed in the middle of the results and yielded to relatively high eruptions. In the first trial, the eruption was 176 cm and the second trial height was 132 cm. In order of highest eruptions to smallest was fruit Mentos, strawberry Mentos, and then green apple Mentos. (For graph and table, please refer to end of paper.) Conclusion After completing this experiment, the results were that the fruit Mentos produced the highest eruption compared to the green apple Mentos and strawberry Mentos. The first trial may have had an error because the geyser tube was not all the way on and may have contributed to the lower height of eruption. The fruit Mentos may have had a rougher surface than the green apple Mentos, but another test would have to be done to confirm that hypothesis. The hypothesis stated before would make an excellent follow-up experiment to determine if that is the reason why the fruit Mentos went higher than the green apple and strawberry Mentos. Another follow-up experiment could be to try tying the Mentos in different ways to force them to the bottom quickly to determine if that has any effect on the eruption height of the Mentos.

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Endnotes 1. Coffey, Tonya. “Diet Coke and Mentos: What is really behind this physical reaction?” June 7, 2007: 554. 2. Coffey, Tonya. “Diet Coke and Mentos: What is really behind this physical reaction?” June 7, 2007: 554-555. 3. Coffey, Tonya. “Diet Coke and Mentos: What is really behind this physical reaction?” June 7, 2007: 554. 4. Coffey, Tonya. “Diet Coke and Mentos: What is really behind this physical reaction?” June 7, 2007: 554. 5. Coffey, Tonya. “Diet Coke and Mentos: What is really behind this physical reaction?” June 7, 2007: 555. 6. Coffey, Tonya. “Diet Coke and Mentos: What is really behind this physical reaction?” June 7, 2007: 555. 7. Coffey, Tonya. “Diet Coke and Mentos: What is really behind this physical reaction?” June 7, 2007: 556. 8. Coffey, Tonya. “Diet Coke and Mentos: What is really behind this physical reaction?” June 7, 2007: 556. 9. Coffey, Tonya. “Diet Coke and Mentos: What is really behind this physical reaction?” June 7, 2007: 552.

Trial 1

Trial 2

Fruit Mento

198 cm

181.5 cm

Green Apple Mento

121 cm

154 cm

Strawberry

176 cm

132 cm

Height of Eruption (in cm)

Height of Eruption with Different Types of Mentos 250 200

Tria l1

150

Tria l2

100 50 0 Fruit Mento

Green Apple Mento Type of Mento

Strawberry

56


Period Seven

The weakening effects of Baking Soda and Sugar on the height of a Mentos in diet coke eruption The first time our group performed the experiment we tested how high five Mentos candies would erupt within a bottle of diet coke. We found that the average height at which it erupted was 131.5 cm. We came to this height by counting how many bricks the eruption went up, and measured the length of each brick in centimeters. Upon adding the baking soda and sugar to the diet coke, the eruption was much less impressive, since it hardly erupted higher than the top of the bottle, at about 11 centimeters for sugar and 8 centimeters for baking soda. The reason that it did not go that high was because by the time we got the Mentos into the coke, it had already begun to react. We can determine that the baking soda and sugar were both weakening factors to the eruption of the diet coke. Vinegar didn’t seem to alter the reaction as much, but it did make it go lower. The height of the eruption with vinegar was 76 centimeters. Introduction For our experiment we decided to verify Tonya Coffey’s results and test the effectiveness of adding baking soda to the diet coke. According to Coffey’s results, when she added baking soda to the soda it erupted to a height of 15.5 feet, or 472 centimeters.x We also wanted to see how sugar added to the soda would affect the eruption. We came to the conclusion that diet coke does not react as well with sugar or baking soda, because our resulting heights for those experiments were much lower than the control. When adding baking soda and sugar to the diet coke at the same time, we saw that each time, the bottle would overflow without adding any Mentos to it. Experiment Gather all Materials needed for the experiment Using a tube that can release objects with the pull of a string, and place five mentos within the tube. Open the diet coke, and as soon as possible place the tube over the coke and drop the mentos in, taking care to tilt the nozzle towards the wall so that the soda leaves a mark that can be measured Measure how high the soda shot upwards, and record the results; this will be your control Add 20 ml of vinegar to the soda and then put the nozzle on and repeat the process Add 20 ml of sugar to the soda and then put the nozzle on and repeat the process Add 20 ml of baking soda to the soda and then put the nozzle on and repeat the process Compile the data and graph it

Results We found through our experiments that baking soda and vinegar lessened the effects of the diet coke and Mentos eruption. Initially when we tested the diet coke it went up 48 bricks, which is equal to 131.5 centimeters. That was the average of three tests we performed. We came to the conclusion that adding sugar would decrease the reaction because when we added it, the soda overflowed before the Mentos even entered the soda, which made it go up only 11 centimeters. The addition of baking soda was equally as unsuccessful in increasing the reaction, because it reacted with the soda before the Mentos went in and only caused it to erupt 8 centimeters. However when we added vinegar we did get a successful reaction, for the average of the three trials was 27.5 bricks which is 76 centimeters. Graph

57


Effect of sugar, vinigar, and baking soda on the height of a mentos eruption 140 120

Height (cm)

100 80 Series1 60 40 20 0 Control

20 ml sugar

20 ml vinigar

20 ml baking soda

Things we added Conclusion

Since the results we found for these additions were harmful to the eruption, we can pretty safely determine that they do not make the coke more open to erupting. We did not think this would be the case, because according to Coffey, baking soda at least should have increased the reaction.x According to NASA even, adding a sugary substance to diet coke should create a reaction with the coke, which shows why we did get a small reaction after adding the sugar.x A possible reason we did not get strong results for when we just added the baking soda, vinegar, and sugar to the bottle is that there was too wide of a nozzle for the soda to escape from, which made it not go as high.x Also the reaction might have started as soon as the sugar was put into the coke, which would have made the mentos less effective.x An additional reason the baking soda might have caused the reaction to slow down, is because baking soda is a base which would take away the acidity of coke.x Also the amounts of coke and variables used were different then the ones done in other experiments, which must have some impact on the results of the experiment.x In the future, other people could place the soda bottle more carefully, or the pull the strings of the gyser more carfully so it doesn’t tip overx, make sure that the bottle wasn’t shaken around before performing the experiment,x and make sure that you’re using all the same flavor Mento’s for the same trial.x x Coffey, Tonya Shea. "Diet Coke and Mentos: What Is Really behind This Physical Reaction?" American Journal of Physics 76.6 (2008): 551. Print. x Coffey, Tonya Shea. "Diet Coke and Mentos: What Is Really behind This Physical Reaction?" American Journal of Physics 76.6 (2008): 551. Print. x Rust, Cashman R. "NASA ADS: Explosive Volcanism Lessons Learned from Mentos and Soda Eruptions." NASA Astrophysics Data Center. American Geophysical Union, 14 Nov. 2006. Web. 10 Oct. 2011.

Voltz, Stephen M. "Nozzle for Creating Geyser-like Fountains." USPTO Assignment Database. Frederick Globe, 21 Sept. 2007. Web. 10 Oct. 2011. x

x

Rust, Cashman R. "NASA ADS: Explosive Volcanism Lessons Learned from Mentos and Soda Eruptions." NASA Astrophysics Data Center. American Geophysical Union, 14 Nov. 2006. Web. 10 Oct. 2011. x Voltz, Stephen M. Effects of an Acidic Beverage on Dental Maintance 08th ser. 36.8 (1996): 1775-781. Antimicrobial Agents and Chemotheropy. American Society for Microbiology, 21 Oct. 1998. Web. 10 Oct. 2011. x Coffey, Tonya Shea. "Diet Coke and Mentos: What Is Really behind This Physical Reaction?" American Journal of Physics 76.6 (2008): 551. Print.

Voltz, Stephen M. Effects of an Acidic Beverage on Dental Maintance 08th ser. 36.8 (1996): 1775-781. Antimicrobial Agents and Chemotheropy. American Society for Microbiology, 21 Oct. 1998. Web. 10 Oct. 2011. x Rust, Cashman R. "NASA ADS: Explosive Volcanism Lessons Learned from Mentos and Soda Eruptions." NASA Astrophysics Data Center. American Geophysical Union, 14 Nov. 2006. Web. 10 Oct. 2011. x Voltz, Stephen M. Effects of an Acidic Beverage on Dental Maintance 08th ser. 36.8 (1996): 1775-781. Antimicrobial Agents and Chemotheropy. American Society for Microbiology, 21 Oct. 1998. Web. 10 Oct. 2011. x

58


The Mixture of Mint and Fruit Mentos Produced the Largest Eruption Jack F and Jamie W

Summary The experiment being tested was if two mentos were dropped into a diet coke bottle, which one would have the highest eruption? The types of mentos that were used were fruit, apple, and mint; and the trials were two mint, two fruit, two apple, one mint one fruit, one mint one apple, and one fruit one apple. Two mint is considered the control due to it being the most common mento. If two mentos are placed into a diet coke bottle, then two fruit mentos will have the highest eruption because fruit mentos have a smoother shell, creating more pressure build up. Once the experiment was performed, one apple and one mint mento combination had the largest eruption, which was 46 bricks high. The next two highest eruptions were two mint mentos at 43 bricks, and one mint one fruit at 40 bricks high. Two apple mentos had the smallest eruption, which only went 27 bricks high. A combination that contained one mint went 100% as high as the control, where as a combination containing apple went 95.3% as high, and fruit went 88.3% as high as the control. Introduction The amount of mentos added to a bottle of diet coke will affect the size of the eruption. With each mento added to a bottle of diet coke, the height of the eruption spray rises proportionally.x Also, different mentos react differently with the diet coke. Fruit mentos are known to react and cause a larger spray than a mint mento would. This is because fruit mentos have a smoother surface, with fewer rough patches, which dissolves faster in the soda.ii Due to the short amount of time it takes for these to dissolve, carbon dioxide bubbles build up inside the bottle. The more buildup of the co2, the more pressure inside the bottle, which forces the soda out of the nozzle faster. x Experimental Section

59


There were three different flavors of Mentos used, mint, fruit and apple; and a total of six different combinations, or trials. The trials were two mint, two apple, two fruit, one mint one fruit, one mint one apple, and one fruit one apple. These different combinations were placed into the nozzle compartment, and when released, dropped into the soda creating an eruption. The height of the eruption was measured in bricks. Procedure Obtain two mint Mentos, a nozzle compartment with pin, and a diet coke bottle Screw the nozzle compartment onto the diet coke bottle, and put the lock pin in place Place the two mint Mentos into the nozzle, secured by the pin Remove the pin, watch eruption and count the height in bricks Record data Repeat for each trial Supplies One pack of mint Mentos One pack of fruit Mentos One pack of apple Mentos One 6-pack of diet coke, 20oz per bottle A nozzle compartment with a loader pin Safety Precautions Always wear safety goggles Stand safe distance away Do not create too much pressure in the bottle, where it will explode Results 46

1 Mint 1 Apple 40

1 Fruit 1 Mint

36

1 Fruit 1 Apple

Height of Eruption (in bricks)

27

2 Apple

33

2 Fruit

43

2 Mint 0

20

40

60

Mento Eruptions Results The combination of 1 mint and 1 apple mentos had the highest eruption. This eruption went 46 bricks high, 3 bricks higher than the height of the second eruption. The second highest eruption was 2 mint mentos, which went 43 bricks high. Next, 1 fruit and 1 mint mento had an eruption height of 40 bricks. From this point there was a drop off it eruption height. 1 fruit 1 apple mentos went 36 bricks, and 2 fruit mentos went 33 bricks high. Lastly, 2 apple mentos 60


erupted to only go 27 bricks high. The reaction between the 2 apple mentos was the only number that stood out as somewhat of an outlier. Conclusion After the conduction of the experiment to search for the perfect combination of Mentos flavors that would have the loftiest of height compared to the other combinations, Fitzgerald and Webb concluded that the grouping of the mint and apple flavored Mentos erupted the to a measure of forty-six bricks high. This result was followed by the combination of two mint Mentos (forty-three bricks high), mint and fruit Mentos (forty bricks high), fruit and apple Mentos (thirty-six bricks high), two fruit Mentos (thirty-three bricks high), and two apple Mentos (Twenty-seven bricks high). The reason for why the recipe of the mint and apple Mentos erupted the highest was partially because two mint Mentos in an explosion were second to the mint and apple candies in elevation. Besides the mint candy being the necessity for a perfect combination of Mentos for a large eruption, the ingredients in the mint and apple candies may have a simultaneous reaction with either each other or with the Coke itself.i Although the two apple candies went the lowest in altitude compared to the other dependant variables, it still combined for an extreme reaction with mint.ii Lastly, for further study, one might somewhat reenact this experiment by attempting to combine three, four or even more Mentos in order to find the arrangement for the perfect Coke and Mentos eruption. In conclusion, Fitzgerald and Webb discovered that the formula of apple and mint Mentos in a Coke and Mentos experiment were the ideal combination to achieve the highest rise of coke from the ground.

61


Manipulating the Surface of Mentos: The Resulting Diet Coke and Mentos Explosion Height will Increase if the Increased Surface Roughness is Greater Than the Losses of Mass and Gum Arabic Juandiego C Summary: In this specific experiment, the surface texture was tested. However, it was discovered that it is extremely difficult to physically manipulate the surface texture of the Mentos without a resulting loss of mass and gum arabic. Therefore, three different groups with different surface roughness increase to mass/gum arabic loss ratios were tested to explore the resulting effects; one group of Mentos was grazed lightly with sandpaper, one had holes poked into it, and one had the coating completely scratched off- were tested. In comparison to the eruption height of a normal Mentos candy, the group with holes went 7% higher, the sandpapered one went 13% higher, and the one with no coating went 25% lower. Introduction: The diet coke and Mentos reaction is a fun experiment for physics and chemistry classes ranging in all different grade levels. The diet coke and Mentos candy eruption occurs when new Mentos are dropped into a freshly opened bottle of diet coke. The eruption can be multiple meters high (the record is 29.2 ft).1 This reaction was first shown on the Dave Letterman Show in 1999 and was the subject of a 2006 Mythbusters episode.2,3 There are few verified discoveries regarding the Mentos and diet coke eruption. Many experiments have inferred that additives, “viscous drag”, and temperature have a large impact on the explosion height. 4 However, it has been cited that surface roughness is a crucial factor of the reaction.5 When the Mentos candy falls to the bottom of the bottle, carbon dioxide bubbles form on it; then they detach and rise to the top. The bubbles act as nucleation sites for carbon dioxide still dissolved in the liquid. This discharges more carbon dioxide and creates a larger explosion.6 The higher surface area results in more growth sites present per unit volume. This theory is proven with Coffey’s experiment. Two of the combinations tested were Wint-o-Green Lifesavers and diet coke and rock salt and diet coke. The Wint-o-Green lifesavers had a rms roughness of 10 more than the rms roughness of rock salt. The Wint-o-Green’s higher surface area is one of the main factors that resulted in its explosion having more distance and losing more mass than the salt and diet coke. 7 In addition, an experiment done by Hill and Gaboury, two students of Guilford High School, showed that drilling holes into Mentos resulted in the eruption going higher than regular mentos.8 The intensity of the Diet Coke and Mentos eruption is moreover due to the presence of gum arabic in the Mentos candy coating.9 Gum arabic is a surfactant that increases the intensity of an explosion by reducing the surface tension of water.10 In Coffey’s paper, the presence of liquid gum arabic in Diet Coke soda caused a reaction without surface roughness.11 However, despite gum arabic’s important contribution to the explosive reaction between Diet Coke and Mentos, it is extremely hard to physically manipulate the surface area of Mentos candies without the losing amounts of it. The purpose of this lab is to further test the relation between these two properties behind the explosion. Experiment: In this experiment, we altered the surface of Mentos three different ways and then measured the height of the reaction between each Mentos and diet coke. We separated the green apple Mentos into four different groups to test our independent variable. With the first group we abraded the surface of the Mentos with sandpaper to create grooves in the surface. The second group we used sandpaper again to remove the candy coating of the Mentos completely, and the third group we used the metal tip of a mechanical pencil to make approximately ten holes in the front and back of the Mentos. The final group we kept the same to serve as a control group to compare the rest of our data to. The constants held in the experiment were the type of mentos, the size of the hole poked in the Mentos, the brand of soda, the bottle size, the extent of grazing on the first group of Mentos, and the number of Mentos used in each trial. After we prepared the Mentos we set up a 355 mL bottle of diet coke against a brick wall. We placed a flat whiteboard beneath the can to keep it from falling over and put soda lids in about a two inch stack under the side of the whiteboard away from the wall. This allowed the soda to splash onto the wall leaving a mark that would make measuring easier. 62


We placed two regular Mentos into a geyser and screwed the geyser on top of the open bottle just prior to the experiment to minimize the loss of carbon dioxide gas. 10 Then, we put on safety goggles, pulled the pin out, and stepped back a safe distance from the eruption. We recorded the number of bricks high the soda reached, and then repeated the step for multiple trials. We did the same procedure for the other three groups of Mentos. Results: The recorded heights for each type of Mentos can be observed in Table 1 and can be compared in Graph 1 or Graph 2. We conducted between three to six trails per type of Mentos. The average height for regular Mentos was 176.0 cm, 198.9 cm for sandpapered Mentos, 188.8 cm for Mentos with holes, and 132.0 cm for Mentos without the candy coating. We chose to use four significant numbers instead of the two that is required for the multiplication and division rules to increase the accuracy of our figures. The percent error for sandpaper is 0.008%, and the percent error for Mentos with holes is 0.03%. The other two groups divided equally as the average. The Mentos with holes in them had a resultant height 7% higher than the control group. The height of the sandpapered Mentos yielded an eruption height of approximately 13% higher than the control group on average, and the Mentos without coating had an eruption height about 25% lower than that of the control group.

63


The Effect of Drop Height on the Height of the Mentos Eruption Summary: For our experiment, we dropped two mentos using 1 geyser tube, 2 geyser tubes, and then 3 geyser tubes to see if the height at which the mentos were released played a role in producing higher eruptions. Throughout the experiment we used the 473 milliliters of Diet Coke for every trial. The average height when using one geyser tube was 136 cm, two geyser tubes increased the height by 3.5 bricks making its average height of 158 cm, and three geyser tubes further increased the height with an average of 196 cm. The results also showed that there was a 16% increase when using 2 geyser tubes instead of 1, a 24% increase from 2 geyser tubes to 3, and a 44% increase from 1 geyser tube to 3 geyser tubes. At the end of the experiment, the results demonstrate that the higher the mentos are released the higher the eruption. Introduction: When the Mythbusters team tested the mentos eruption they found that the speed with which the sample falls through the liquid is a major factor in contributing to higher explosions. If the bubbles [produced during drop] must travel farther through the liquid, the reaction will be more explosive. Longer distances traveled by the bubbles result in more explosive reactions. In contrast, the mentos released from 1 geyser tube produce particles moving through the fluid at a slow speed, since they do not gain as much velocity, and do not travel as far down into the bottle. The Mythbusters further concluded that samples, which encounter less viscous drag and hence fall more quickly through the soda, will cause more explosive reactions. Experimental Section: This experiment is being used to see if the height of the drop of mentos has a noticeable effect on the height of a menots eruption. During this experiment, there will be three lengths of geyser tubes. 1 geyser tube, 2 geyser tubes taped together, and 3 geyser tubes taped together. These should be duck taped together very well to ensure that no cracks let eruption foam out of the sides. Results: The Effect of Drop Height on the Height of the Mentos Eruption Height of Eruptions (cm) Number of geyser tubesTrial 1 Trial 2 Trial 3 Trial 4 Average 1 152 152 127 114 136 2 158 158 152 165 158 3 190 215 177 203 196 Our data shows that the higher the mentos were dropped, the higher eruption it produced. For example, the average for the 1 geyser tube drop was 136 cm, the average for the 2-geyser tubes drop was 158 cm, and the average for the 3geyser tubes drop was 196 cm. This shows that as the height of the drop increased the eruption height of the mentos increases as well. There is no suspect data in this experiment because all of the numbers are close together for each height drop range. Experimental Procedure: These are the steps to follow in order to perform this experiment. It is important to have safety goggles on during the entire experiment. 1. Place 2 fruit Mentos in 1 geyser tube connected to the 16 oz. bottle of diet coke making sure they do not fall directly through. 2. Place the soda on a flat surface and then release the Mentos and record the height of the eruption. 3. Repeat steps 1 and 2 three more times 4. Gather 2 geyser tubes and connect the two with duct tape and then place the Mentos in the top tube making sure they stay in place. 5. Release the Mentos into the soda from a flat surface and record the height of the eruption. 6. Repeat steps 4 and 5 three more times 7. Now with 3 geyser tubes, connect all three of them with duct tape and drop the 2 fruit Mentos into the top tube. 8. Release the Mentos into the soda with a flat surface underneath and record the height of the eruption. 9. Repeat steps 7 and 8 three more times 64


Conclusion: At the end of the experiment, from the results that were collected, we discovered that the higher Mentos are dropped, the higher their eruption will be. The results from the experiment supported the Mythbusters theory from the work of Coffey because dropping the Mentos using 3 geysers tubes versus 1 geyser tube shows a significant difference in eruption height because the Mentos dropped from the top of 3 geyser tubes have more velocity; therefore, they fall farther down in the soda bottle. This is shown several times throughout the data because as it can be seen in the graph and table above, the height of the eruption is always higher for the higher drop distances. For example, in trial 2 for all of the heights, the 3-geyser tube drop is significantly higher than the other 2 drops with 1 and 2 geyser tubes In addition, in many of the trials, the data is never any close than 6 cm in height difference, which is a sizeable margin. If higher drop heights were tested, the data would most likely be linear because the height of the Mentos eruption would increase at a steady rate as the drop height increased and our data supports this concept. Perhaps at a certain drop height it could break the world record. The reason for these results could be that as the Mentos drop they gain more velocity, therefore creating a larger explosion. In the future, there could be multiple follow-up experiments to further solidify the position that the higher Mentos are dropped into diet coke, the larger eruption will occur. For example, there could be an extended experiment on this one that was performed, where the height is dramatically increased, and it tests how extreme the results can become.

65


Mentos, Baking Soda, and Vinegar….A Quench to an Eruption’s Thirst. Rebecca E and Klaire C Summary The experiment completed consisted of using additives (baking soda and vinegar) to a soda and mentos eruption. The control of the experiment (1 mento and 1 bottle of soda) reached a height of 35 bricks. The first trial which consisted of ½ teaspoon of baking soda and 1 teaspoon of vinegar reached a height of 13 bricks. The second trial which had ½ teaspoon of baking soda and 2 teaspoons of vinegar reached 32 bricks. The third trial had ½ teaspoon of baking soda and 3 teaspoons of vinegar reached 13 bricks. And finally the fourth trial which had ½ teaspoon of baking soda and 4 teaspoons of vinegar reached a height of 0 bricks. Overall it was found that the more vinegar that was added to the mixture, the lower the eruption height was. Introduction The Mentos eruption is an experiment that can be changed in multiple ways. It has been seen on Mythbusters (3) and the David Letterman Show (4). Kids and adults of all ages have tried their own version of the “Diet Coke and Mentos” (10). Our experiment involved using additives (baking soda and vinegar) to see if it would increase the height of the eruption. We used baking soda at a constant of 2.5 grams and increased the amount of vinegar for each of the 5 trials. Robins and Turcio (2) had the same idea in which they referred to it is as a “volcanic eruption”. Diet Pepsi was found by Musterer and Ruotolo (1) to have a higher eruption than diet Coke. They determined that the additives almost entirely quenched the eruption. Cutler and Smith discovered that frozen mentos dramatically increase the eruption (7). The other resource we had, the article by Tonya Coffey, did not have any information about our specific experiment but it did have useful conclusions such as the higher temperature of the soda causes a greater eruption (6). The speed at which the mento is dropped is also a major factor in the eruption along with the idea that gum arabic and gelatin in mentos and potassium benzoate and aspartame in caffeine cause explosion (5, 9). In the experiment, there was a period of 15 seconds before the mento was dropped into the diet coke solution, therefore, adding water, sodium acetate, and carbon dioxide to the eruption. There was no information on these substances in our sources, but we can conclude that they altered the eruption because it added more to it. This made our experiment more complex than we had intended because there were five additives instead of the two that were intended. The additive creates the reaction NaHCO3 + CH3CO2H – CH3CO2Na + H2O + CO2. This reaction and the baking soda and vinegar solution quenched the overall eruption.

Experimental section Trial number Amount of baking soda Amount of Vinegar CONTROL 0 grams 0 teaspoons 35 bricks 1 (.5 teaspoon) 2.5g (1 teaspoons) = 4.9289 mL 13 bricks 2 (.5 teaspoon) 2.5g (2 teaspoons) = 9.8578 mL 32 bricks 3 (.5 teaspoon) 2.5g (3 teaspoons) = 14.7867 mL 13 bricks 4 (.5 teaspoon) 2.5g (4 teaspoons) = 19.7156 mL 0 bricks

Height of eruption

The experiment done here was based on using additives. The first step was to obtain (6) 8 oz bottles of diet coke, baking soda, white vinegar, a teaspoon, mint mentos, and a geyser tube. The first step in the process of the eruption was to run a control. This means nothing is added to the soda but a mento and a geyser tube, the string is pulled, and the height of eruption is recorded. Then the next step is to run the first trial of the experiment. The first step 66


is to cover the teaspoon in a coating of baking soda so that the spoon is half filled with baking soda. Then the vinegar is poured into the spoon and added into the soda. A minor eruption occurs here so waiting 15 seconds after the eruption helped to keep the experiment more accurate. Then a geyser tube is inserted into the soda with a mento into the soda and the height of eruption is recorded. For each trial, the amount of baking soda is constant but the amount of vinegar is increased. Now all steps can be repeated for each trial. Results *note: trial 1 is an outlier so that data will not be included in graphs. *note: all conversions were done online on Google calculator. ***note: observation: the more vinegar that is added the lower the final eruption will be

Conclusion With the provided data, it is suggested that if a constant amount of baking soda and increased amount of vinegar is added to a Mentos eruption, the more vinegar there is, the lower the eruption will be. The control in the experiment with no baking soda or vinegar went a height of 35 bricks. But as soon as more baking soda and vinegar was added, the eruption significantly lowered each trial, going from a height of 35 bricks, to 32, to 13, to no bricks. The amount of baking soda remained constant in every trial, but the amount of vinegar in each trial was increased. When at its maximum amount, the amount of vinegar was 4 teaspoons and there was no eruption, even with baking soda added to the mixture as well. This compares to the control of 35 bricks with no additives in the solution, making a difference of 35 bricks. Another comparison that can be made is to the third trial. The total eruption height was 32 bricks, as opposed to the end result of 0 bricks. It is very clear that the amount of vinegar in a Mentos eruption has a significant effect on eruption height, obviously lowering the overall eruption height. Now the question of why did this happen comes up. A potential reason as to why vinegar quenches the eruption could be because of an imbalance of baking soda and vinegar. In a typical baking soda and vinegar reaction, there is always a huge explosion but when the amounts of both additives are altered it could affect the explosion. Another thought as to why the vinegar could have affected the explosion is because the baking soda mainly caused a minor eruption in the soda by itself when it was first added to the mixture, so by adding the vinegar it could have caused a reverse reaction where it did the opposite of what it normally does in a typical reaction because soda is in the mix. Finally, if the experiment was done over again more trials would be added for more data points, more accurate measurements would be taken, more precise procedures would also be taken to prevent invalidity of data, and more additives and background research would have been done to get a more clear understanding of the experiment before it was started. Citations 7. Rachel Cutler and Emma Smith, Guilford Journal of Chemistry, Volume 1, Pages 6-12 (2007). 1.Angelise Musterer and Lindsay Ruotolo, Guilford Journal of Chemistry, Volume 2, Pages 12-14 (2008). 2. Kelsey Robins and Laura Turcio, Guilford Journal of Chemistry, Volume 2, Page 38 (2008) 3. Mythbusters. Videocassette. Discovery Channel, 2006. 4. The Late Show with David Letterman. Videocassette. CBS, 1999. 5,6,8,9,10: Tonya Coffey, Diet Coke and Mentos: What is Really Behind This Physical Reaction?

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Which Soda Provides the Best Mentos Eruption; Diet Coke, Sierra Mist, Mountain Dew Rebecca E and Klaire C

Coke Zero, Diet Pepsi, Sprite, Club Soda: Summary: For this Mentos Eruption, the sodas used were Diet Coke, Sierra Mist, Mountain Dew, Coke Zero, Diet Pepsi, Sprite, Club Soda, the goal was to see which soda produced the highest eruption. This variation of soda helped the observer see how different variables directly affect the height of the sodas eruption. This experiment the researchers found that Diet Coke caused the highest eruption out of all the sodas tested with an average of six bricks or thirty-three centimeters. Mountain Dew, Sprite, and Club Soda all fell short with an average of two bricks or eleven centimeters. Coke Zero came in second with an average of five or twenty-seven and a half centimeters. Diet Pepsi came in third with an average of four bricks, or twenty-two centimeters. This directly contradicts the work of Angelise M & Lindsay R. Through all this data a mathematical formula can be created where X is equal to the soda and Y equals the height and Y=X. Introduction: In earlier tests done by other researchers to find the soda that provides the best soda eruption, Diet Coke had been used. In this experiment the data shows that is because it does, in fact provide the best Mentos eruption. In an experiment done by Tonya Shea Coffey1, Coffey’s data supports the facts of “Which soda provides the best Mentos eruption; Diet Coke,” where Diet Coke provides the best Mentos eruption. Yet, when this data was compared with “Diet Pepsi –Not Diet Coke – Produces Highest Results in Mentos Eruption When Compared to Other Diet Carbonated Drinks” By Angelise & Lindsay R, it was found that the data was not supported and Diet Pepsi had the highest eruption. In the “Introduction to the second issue of the Guilford Journal of Chemistry, M and R’s3 data on Diet Pepsi is said to be 100% higher relative to Diet Coke. In another study, “The Effect of Soda Type on the Height of Mentos Eruptions,” by Ethan S and Zack B, data supported the data of “Which Soda Provides the Best Mentos Eruption; Diet Coke, Sierra Mist, Mountain Dew Coke Zero, Diet Pepsi, Sprite, Club Soda: Diet Coke!” with Diet Coke being Shore and Browns’5 highest soda eruption too. The experiment “Which Soda Provides the Best Mentos Eruption; Diet Coke, Sierra Mist, Mountain Dew, Coke Zero, Diet Pepsi, Sprite, Club Soda: Diet Coke!” used strawberry, fruit, Mentos, which Coffey1 found to help make the largest eruption. In an experiment completed by Allison F and Jess L, they found that mint Mentos and Fruit Mentos have the same size eruptions. In an experiment in the American Journal of Physics, Fruit and Mint Mentos were found to have the same size eruptions also. Unlike K and R from the “Introduction to the Second Issue of the Guilford Journal of Chemisty,” the experiment, “Which Soda Provides the Best Mentos Eruption; Diet Coke, Sierra Mist, Mountain Dew, Coke Zero, Diet Pepsi, Sprite, Club Soda: Diet Coke!” did not cut the Mentos in half before adding them into the soda, they kept them whole. Experimental Section: The experiment that was done, by Rebecca E and Klaire C, was accomplished by having three trials, per soda, completed. With-in each trail a single Mento was dropped into a freshly opened bottle of twelve-milliliter bottle of soda. Results: Trial 1 Trial 2 Trial 3 Diet Coke 33 cm 33 cm 33 cm Sierra Mist 16.5 cm 11cm 11 cm Mountain Dew 5.5 cm 11 cm 16.5 cm Coke Zero 33 cm 27.5cm 22 cm Diet Pepsi 16.5 cm 22 cm 27.5 cm Sprite 11 cm 11 cm 11 cm Club Soda 22 cm 0 cm 11 cm (Each Brick is equal to 5.5 cm)

68


Conclusion: For our experiments, we found that out of the seven sodas we used, Diet Coke worked the best. For all three of the trials, Diet Coke’s foam shot up an average of 6 bricks, 33cm. The soda that had the next largest foam height was Coke Zero with an average of 5 bricks, 27.5cm and the third largest foam height was Diet Pepsi with 4 bricks, 22cm. According to Ethan S and Zack B, Diet Coke had the second largest explosion with an average of .85m and Sprite had the 3rd largest explosion, with an average of .51m1. Our results are not completely accurate because the first day of experimenting we did not have a string so we had to substitute a stick for it. The stick could have had a negative effect because it was thicker than the one attached to the string that we used the second day. Also, when we pulled both the sting and the stick sometimes the soda would fall over causing the data to be not as accurate as it could have been. “Sometimes, my hand partially hit an explosion, perhaps causing the height to drop” 2, like the picture shows on the right. The same thing happened in our experiment as well. A follow up experiment would be to try the different sodas with a different type of Mentos to see if the different flavors have an effect with the sodas. Something else we could do, would be to try less types of soda and do more trials to get our data more accurate. Experimental Procedure: 1. Get 12 ounce bottles of Sprite, Coke Zero, Diet Coke, Diet Pepsi, Club Soda, Mountain Dew and Sierra Mist as well as Mentos. 2. Open bottle and attach the geyser tube. Attach the string and drop the Mento in. 3. Pull the string and measure how high the foam goes. Record it in a data table. 4. Repeat steps 2-3 for each bottle. Endnotes: 1.“Diet Coke and Mentos: What is really behind this physical reaction?”, Tonya Shay Coffey. Received 7 June 2007; accepted 5 February 2008. Pages: 551, 552, 553, 556. 2. “Guilford Journal of Chemistry” (First- Second Issues) Editor and Chief: Dr. H. Breilmann. Pages: 1,2,3,4 3. “Diet Pepsi –Not Diet Coke – Produces Highest Results in Mentos Eruption When Compared to Other Diet Carbonated Drinks”, By Angelise M & Lindsay R http://chemistryadventure.com/Documents/b2.%20Diet%20Pepsi,%20not%20diet%20coke%20is%20the%20highest.pdf 4. “Cinnamon Mentos Erupt 20% Higher than Mint Mentos”, By Allison F and Jess Lhttp://chemistryadventure.com/Documents/b1.%20Cinnamon%20Mentos%20Erupt%2020%20percent%20higher.pdf 5. “The Effect of Soda Type on the Height of Mentos Eruptions”, By Ethan Sand Zack B. http://chemistryadventure.com/Documents/b9.%20The%20Effect%20of%20Soda%20Type%20on%20the%20Height%20 of%20Mentos%20Eruptions.pdf

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The Guilford Journal of Chemistry Volume 6 2012-2013



Table of Contents: Three-dot Nozzle Causes an Eruption Averaging 32.7% Higher than Commonly-Used One-Dot Nozzle By: Allison B, Sammy C, and Ashley H………………………………….…. …4 An Increased Drop Height Causes Only 0.3 grams Less Soda to Leave the Bottle During a Diet Coke and Mentos Eruption; Evidence of Very little Change By: Rachel G. and Emily S………………………………………………………………………..8 Mentos Mashed Into a “Pancake” Erupt, on Average, 48% Lower than Regular Mentos By: Henry R. and John R……………………………………………………………………………….....12

Loud Low Pitch Sounds Produce a 21% Increase in Eruption Height When Mixing Minty Mentos With Regular Coca Cola By: Jack D. and Kyle E....……………………...…………….17 Sprite Zero Erupts 7% Higher than Diet Coke in Comparison to Four Sodas By: Lucila K. and Lindsay L……………………………………………………………………………………………..20

The Diet Coke and Mentos Eruption Using the Standard Geyser Tube Erupted 52.3% Higher than the Modified Nozzle By: Jackson I., Sonny C., Tim K………..……………………23 Minimizing the CO2 Lost During the Application of the Geyser Tube Increases the Pressure within the Bottle but Decreases the Height by 8.54% By: Kate V. and Sophie K…….27 Mentos Heated to 30º Celsius Cause an Eruption of Diet Pepsi 32.8% Higher Than Mentos at 25º Celsius. By: Cole H., Sean H., and Logan F………………………………………………...31 Amount of Carbonation Matters - Height of Eruption Decreases 80% When Diet Coke Bottles Opened 48 Hours Prior to Eruption By: Jaimie C and Becca W………………………..38 Coated Fruit Mentos Produce an Eruption Height 35.9% Greater than Those with Removed Coating Report by: Joe I. Tested by: Isaac A. Chris C. and Joe I……………………..42 Crushed Mentos Create an Eruption that is, on average, 44 cm Less than Full Mentos By: Laurel Z. and Ashley I. ..……………………………………………………………………48 The Effect of Different Diet Soda Brands on the Height of Mentos Eruptions By: Mackenzie C. Natalia P. Amanda P……………………………………………………………...50 Whole Mentos Have a 15% Increase of Eruption Height Compared to Mentos that Were Broken into Halves and Quarters By: Morgan D. and Sami C………………………………….55 The Larger Tube Angle, 360˚, produces a 65% Decrease in the Height of the Mint Mentos Eruption in Comparison to a 0˚ Tube Angle By Sydney S. and Krissa C…………...….59


The Effect of Putting 5,7,9, and 11 Mentos to Change the Height the Soda Erupts to 92 Bricks By: T.J. W, Luke N…………………………………………………………………..…..63 Mint- Fruit Combinations Can Erupt 8% Higher than Mint or Fruit Alone in a Mentos Eruption By Grace C. and Madisen P……………………………………………………………66 Various Holes and Designs Placed On Tape Can Significantly Affect Mentos Eruption By Kathryn B. and Katie E………………………………………………………………………70


Three-dot Nozzle Causes an Eruption Averaging 32.7% Higher than Commonly-Used One-Dot Nozzle By: Allison B, Sammy C, and Ashley H.

Summary: The “Coke and Mentos Experiment” is an experiment to find out what happens when Mentos are dropped into a bottle of Coke, or another carbonated drink. The result of the experiment is a reaction in which the soda explodes through the top of the bottle. The results can be different according to your independent variable. By putting Mentos through the neck of the bottle, it causes a reaction between the carbon dioxide in the soda and the coating of the Mentos. In the experiment, it was proven that the smaller the nozzle shape is, the higher the eruption went. This is due to the fact that the smaller hole creates more pressure for the soda to fit through. It was found that the lowest eruption height was the control trial with no nozzle that only reached an average height of 10.5 bricks. The second lowest reaction was the cross cutout which had an average height of 42.5 bricks. The next lowest reaction heights were the one dot nozzle and the line nozzle which had an exact same average of 53.5 bricks high. The highest eruption height was the three dot nozzle which had an average eruption height of 71 bricks. The three dot nozzle went an average of 576.2% higher than an eruption with no nozzle, 67.1% higher than the cross nozzle, and 32.7% higher than the line and one dot nozzles. Introduction: The “Coke and Mentos” phenomenon was first introduced in the 1990’s when David Letterman had it on his show in 1999. The experiment has also shown up on television shows such as Mythbusters and Time-Warp and has become a challenge on YouTube. Many variables have been tested to try to beat the world record of an eruption height of 26ft. We believed that changing the nozzle on the geyser tube would affect the height of the eruption. In the eruption done by GHS students Gabriella Necklas and Kierstan Wall, they found that a round, smaller hole produced the highest eruption.1 Our prediction was that the smallest dot nozzle would have the highest height, because the pressure of the soda would be greater going through the smaller hole. This was proven correct; it went an average height of 71 bricks. In a previous experiment testing the effect of nozzles with different diameters, it was found that the nozzle with the smallest diameter had the highest reaction. This was the reaction done by Aaron Davis and Travis Dillon, in which they found that the smallest hole produced the highest height.2


Experimental Section: Materials:         

Fifteen 12.9 oz. bottles of Diet coke 8 packages of fruity Mentos 1 geyser tube Four different shaped nozzles Masking tape Trash Bags Pencils and paper Goggles A tilted, flat surface against a brick wall

Procedure: 1. Get all materials needed for the experiment 2. Place masking tape on the wall as markers of every ten bricks, as high as you can reach 3. Put all six Mentos inside geyser tube and make sure that the needle is inserted in the bottom of the tube so they don’t fall out 4. Screw on whichever nozzle (or lack thereof) is being tested 5. Unscrew diet coke cap and place the soda on the platform at an angle that will cause the eruption to barely hit the wall 6. Screw on geyser tube on top of the diet coke bottle 7. Have one person holding the bottle with another person pulls the pin/needle out of the tube 8. Record the height of eruption by seeing where the eruption stained the wall and counting the number of bricks 9. Repeat steps 3-8 for each nozzle trial or control


Average Percent Higher than Each Nozzle Nozzle Shape Average Percent higher than control Average Percent higher than cross nozzle Average Percent higher than 3 dot nozzle Average Percent higher than line nozzle Average Percent higher than one dot nozzle

Control

Cross Nozzle

3 Dot Nozzle

Line Nozzle

One Dot Nozzle

0%

304.8%

576.2%

409.5%

409.5%

-75.3%

0%

67.1%

25.9%

25.9%

-85.2%

-40.1%

0%

-24.6%

-24.6%

-80.4%

-20.6%

32.7%

0%

0%

-80.4%

-20.6%

32.7%

0%

0%


Conclusion: In conclusion, we found that the 3 dot nozzle created the highest eruption overall. We did three trials for each nozzle, which causes less error; however, more trials could have been done to further eliminate error. Different errors that could have caused the results to be skewed were that although we always used fruity Mentos, we used strawberry for some trials and apple for others. Also, the time it took to put the geyser tube on the soda was not always the same, possibly causing more or less carbonation to be lost, which affects the height of the eruption.6 Our results were consistent with the results in past experiments,1,2,4,5,6 that the smaller the nozzle is, the higher the eruption will go. This supports the accuracy of our data, and shows that although there could have been minor errors, our results are still reliable. Different shapes and diameter nozzles have been tested over the years, and we believe that the three dot nozzle is the ideal nozzle, because it has round, small holes that cause the greatest pressure and therefore the greatest height. References: 1. Gabriella Necklas and Kierstan Wall. The Guilford Journal of Chemistry. Volume 1, pages 23-25 (2008) 2. Aaron Davis and Travis Dillon. The Guilford Journal of Chemistry. Volume 1, pages 1213 (2008) 3. Olivia S. and Bronwyn R. The Guilford Journal of Chemistry. Volume 5, pages 51-53 (2012) 4. Taylor S. and Rosie S. The Guilford Journal of Chemistry. Volume 1, pages 14-15 (2008) 5. Evan H. and Michel I. The Guilford Journal of Chemistry. Volume 5, pages 15-17 (2012) 6. Shane G. and Clara P. The Guilford Journal of Chemistry. Volume 5, pages 26-29(2012)


An Increased Drop Height Causes Only .3 grams Less Soda to Leave the Bottle During a Diet Coke and Mentos Eruption; Evidence of Very little Change

By Rachel G. and Emily S.

Summary: In this experiment, the combination of Mentos and diet coke to create an eruption was tested with 2 different drop heights. One was tested with a drop height of 0 cm (the control), and another tested at a drop height of 68 cm. This was to affect the different rates of the Mentos dropping into the soda, and in the end, the results provided .3 more grams of soda lost from the control than the height. This miniscule number showed that the drop height did not change the results of the eruption in any significant way.

Introduction: The famous Diet Coke and Mentos experiment is executed by opening a bottle of Diet Coke and dropping in newly-opened Mentos, causing the soda to spray up and out of the bottle. Depending on differing variables, the eruption heights can be either a few inches or a few feet tall.1 This experiment is most commonly used in classroom settings, from an elementary level all the way to college, and it has been tested on the popular show Mythbusters in an episode from 2006.2 The effect is caused by gum arabic and gelatin in the Mentos reacting with the caffeine, potassium bensoate, and aspartame in the Diet Coke. 3 In our own version of the reaction, we experimented whether the drop height of the Mentos affects the amount of soda left in the bottle. Last year, a similar test was done, but the students instead measured the height of the eruption. They discovered that the higher the Mentos was dropped, the higher the eruption. 4 They reasoned that this effect was caused by the increased velocity of the Mentos as they are dropped from a high height.5


Experimental: 1. Gather 6 small bottles of Diet Coke, at least 2 packs of mint Mentos, a tube at least 3 centimeters wide and 68 inches long, a scale, and some kind of platform. 2. Place a bottle of soda on the platform, outside preferably and prepare by getting one Mento out and putting on safety goggles. 3. Screw the cap off the soda and as quickly as possible drop the Mento into the soda. 4. Allow the soda to fizz completely and then set the soda aside, carefully noting that the soda had no drop height. 5. Repeat steps 2 through 4 twice. 6. Place the soda on the platform, preparing now with a Mento and the tube. 7. Screw the cap off the soda. As quickly as possible, place the tube over the open top and drop the Mento into the soda through the tube. 8. Pull the tube away from the soda as quickly as possible so as not to interrupt the eruption. 9. Allow the soda to fizz completely. Then, mark it clearly as a soda with drop height. 10. Repeat steps 6 through 9 twice. 11. Wait until all the sodas are finished fizzing. Then, weigh each soda on the scale and record each measurement in a data table in grams. 12. To find the exact weight of only soda that left the bottle, weigh a full bottle of the same type and subtract the remaining soda values for exact data. 13. Find the averages of the trials.


Results: Amount of Soda Lost (g) control (0 ft)

height (68 ft)

Trial 1

186.9

188.8

Trial 2

196.8

201.2

Trial 3

197.9

190.7

Average

193.9

193.6

Amount of Soda Lost by Eruption 205

200

grams

195

control (0 ft)

190

height (68 ft) 185

180

175 Trial 1

Trial 2

Trial 3

Average


Conclusion: When the Mentos dropped into the diet coke at 0 cm, and then at 68 cm, a distinct difference was not detected. Unlike most experiments measuring the height of the eruption, this experiment couldn’t use geyser tubs, and therefore the amount of soda lost was measured to produce numerical data. Tested with 3 trials for accuracy, when the trials were averaged, the difference between the soda lost with a Mento dropping from 0 cm and from 68 cm was less than 1 gram of a difference, which could have been due to other circumstances such as the amount of time the bottle was opened for. The control lost 193.9 g of soda, and the height lost 193.6 g of soda. Perhaps 68 cm wasn’t enough of a height to affect the rate of the Mento for differing results, but a clear conclusion can be made from this experiment. A different drop height did not change anything about the eruptions, which differs from the results of the group who tested this last year. 4 The reason for there being only one changed height is that another experiment based on drop height was primarily worked on, but didn’t succeed. In the ideal experiment, Mentos would be dropped through a long and clear plastic tube fitting exactly around each bottle. Then with meter sticks attached to the tube, the height that the coke reaches inside of the plastic tube would be recorded. A string would allow the Mentos to drop from different points in the tube. For further experimentation, more advanced mechanical endeavors would need to be accomplished in order for this experiment to succeed. When tried, the coke leaked out of the bottom, and the only clear tubes were bendy plastic and didn’t drop the Mento fully. So instead, a quick compromise was done with an hard opaque plastic tube to at least receive some results on this topic. The idea of the procedure was interesting, but nearly impossible to make in the classroom time provided. Some error may also have occurred, such as some Mentos hitting the rim of the bottle or the differing times between opening and erupting. However, this is a fascinating experiment and should definitely be experimented further.

Endnotes: Tonya Shea Coffey, “Diet Coke and Mentos: What is really behind this physical reaction?” Am. J. Phys. 551, 76 (2008). 1

2

ibid, p. 551.

3

ibid, p. 551.

“The Effect of Drop Height on the Height of the Mentos Eruption,” Guilford Journal of Chemistry. 8485 (2011). 4

5

ibid, p.84.


Mentos Mashed Into a “Pancake� Erupt, on Average, 48% Lower than Regular Mentos By Henry R. and John R. Summary A Mentos and Coke eruption, a popular subject of YouTube videos, occurs when Mentos are dropped into a fresh bottle of Coke. Once they are dropped in, a fountain of sweet, sticky, and bubbly spray shoots out of the bottle, reaching great heights (the world record is 29.2 feet). In our experiment, we took Fruit Mentos and prepared them to be dropped into 12-oz. bottles of Diet Coke. We either put them into the Coke without modifying them or mashed them together between two wooden blocks before rolling them up and putting them into the geyser tube. While we were expecting the mashed Mentos to cause a higher eruption (because of their increased surface area), the regular Mentos achieved almost double the height of the mashed ones: regular Mentos caused an eruption of, on average, 165.67 centimeters in height, whereas the mashed Mentos created an average eruption height of only 86.67 centimeters, or about 48% lower (it should be noted that we also attempted this with Mint Mentos, but we were unable to use the same type of soda throughout the experiment, which makes that data very questionable).


Introduction In an article published by Tonya Shea Coffey of Appalachian State University, she cited one of the causes of the Coke and Mentos eruption as surface roughness: the rough surface of the Mentos provides more growth sites for carbon dioxide bubbles in the soda, and thus a huge release of gas that causes the soda to shoot out of the bottle.1 There were also other experiments, published in The Guilford Journal of Chemistry, that had to do with the topic we chose. In an experiment by Nick Hill and Kyle Gaboury, they found that Mentos with a hole drilled into them produced an eruption of 120 cm, higher than powdered Mentos, Mentos with the coatings removed, and regular Mentos.2 In another experiment, it was found that by cutting the Mentos in half, one could achieve an eruption 33 cm higher than an eruption from regular Mentos, and 23 cm higher than an eruption from crushed Mentos.3 In an experiment published by Diana C. and Sarah G., it was found that solid Mentos erupted 5.4 times higher than crushed Mentos.4 Also, in an experiment published by Alicia R., Sarah R., and Casey S., they found that regular Mentos erupted higher than Mentos cut in halves, quarters, or crushed.5 An experiment by Rachel C. and Rachel M. found that changing the shape of the Mentos by melting them and rolling them up resulted in an eruption 39 cm lower than normal Mentos.6 Also, an experiment performed by Grace I. and Amanda M. found that scratching sides of Mentos increases eruption height greatly.7 There was a lot of conflicting data on this type of experiment already, with some experiments showing that increasing surface area created a higher eruption, and with other experiments showing that increasing surface area created a lower eruption, so we were not sure what to think.

Experimental

1. Obtain a few rolls of Fruit Mentos and some 12-oz. bottles of Diet Coke. 2. Take three Fruit Mentos and mash them into a thin pancake between two small wooden blocks or whatever else will do the job (the back of a large spoon and a countertop?...)—we have found that mashing them together one at a time makes the thinnest and most malleable pancake. 3. Roll that pancake around a pencil so that it will fit into and fall through a geyser tube (easily available from your science teacher or scientific websites). 4. Repeat steps 2-3 two more times. 5. Obtain 9 more Fruit Mentos but do not mash them. 6. Go outside to a wall, preferably a brick one (if a brick wall cannot be found, bring a measuring tape or meter stick). Make sure that you are wearing safety goggles. 7. Open the top of the geyser tube and drop in one of the pancakes. Screw the top back on. Make sure that the pin stopping the pancake from falling through is in place. 8. Open a full, fresh bottle of your Diet Coke, place it on a level plane at the bottom of the wall and (quickly!) screw on the geyser tube. 9. Pull out the pin and measure the height of the Diet Coke spray in centimeters (1 brick=7cm). If the pancake does not fall completely into the bottle, you can push it in with a pencil. 10. Repeat steps 7-9 two more times (try to use new geyser tubes each time to prevent stickiness). 11. Repeat steps 7-10, but this time use three of the unmashed Fruit Mentos in place of each pancake.


Results Paragraph In our first trial set, regular Mentos produced an eruption with a height of 147 cm, while the mashed Mentos created an eruption of 91 cm in height. In the second set, the regular Mentos created an eruption of 154 cm in height, while the mashed Mentos, which failed to go into the bottle on their own and had to be pushed in with a pencil, created an eruption of 84 cm in height. In the third set, the regular Mentos created an eruption of 196 cm in height, while the mashed Mentos, which again had to be pushed, created an eruption with a height of 91 cm. This averages out to about 165.67 cm in eruption height for regular Mentos and 86.67 cm in eruption height for mashed Mentos. Data Table

Regular (Unmashed) 147 cm 154 cm 196 cm 165.67 cm

Trial 1 Trial 2 Trial 3 Avg.

Mashed 91 cm 84 cm* 91 cm* 86.67 cm

*Mashed Mentos had to be pushed into bottle

Graph

Mashed Mentos Create a Much Lower Eruption than Regular Mentos 165.67 180 86.67 Series1

(

A v e r a g e

160H 140e 120 S i 100 p g 80 r h 60 a t 40 y 20 0c m )

Regular

Mashed Quality of Mentos


Conclusion In our experiment, we found that Mentos that were mashed into a pancake erupted significantly lower than regular Mentos—by almost 50%. This seemed to somewhat confirm the findings of Rachel C. and Rachel M.6, Alicia R., Sarah R. and Casey S.5, and Diana C. and Sarah G.4, in that they all demonstrated that unmodified Mentos produce a higher eruption than Mentos that have been modified in some way. However, the other experiments (those done by Grace I. and Amanda M.7, Emily’s Ring and Kipness3, and Nick Hill and Kyle Gaboury2), which all demonstrated that modifying the surface areas of the Mentos correctly would produce a higher eruption, seemed to be contradicted by our data. However, when one looks at our methods more closely, one can see where we might have gone wrong. We assumed that, by mashing the Mentos, we would be increasing their surface area and creating a higher eruption. In the process of mashing, however, we may have actually decreased the surface roughness of the Mentos by flattening the small growth sites of the carbon dioxide that were described as one of the main causes of the eruption by Tonya Coffey in her paper1. There were also some smaller errors that included not precisely measuring the spray (we just counted by bricks), slightly different heights against the wall at which the soda bottles rested, having to push in two of the three Mentos pancakes with a pencil because they didn’t fall into the bottle, and some of the bottles of soda fizzing over when we opened them, which may have caused some loss of carbon dioxide. However, these small errors are not enough to have significantly altered our data (one of the pushed-in pancakes created a spray just as high as one that fell in naturally), and we stand by our data as sound. There could be some interesting follow-up experiments to this one, though. Since Mentos have a chewy interior (which allowed them to be molded into a pancake) surrounded by a crunchy exterior, one could try scraping off the exterior coating and putting that coating in the soda instead. One could try mashing the pancake and then leaving it to dry, as well; it would be interesting to see what would happen to that malleable interior. Would it form a rough surface of its own? One could modify the heat at which it was dried, the length of time for which it was dried, maybe even put it in the freezer. It would be an interesting experiment.

Endnotes 1

Tonya Shea Coffey. “Diet Coke and Mentos: What is Really Behind This Physical Reaction?” American Journal of Physics. Vol. 76, No. 6: 551-7 (2008). 2 Nick Hill and Kyle Gaboury. “Drilling a 5 mm Hole in a Mentos Candy Results in a 20% Increase in Erupton Height.” The Guilford Journal of Chemistry. Vol. 2: 38 (2008). 3 Emily’s Ring and Kipness. “Mentos Sliced in Half Will Double the Height of a Mentos Eruption.” The Guilford Journal of Chemistry. Vol. 2: 38 (2008). 4 Diana C. and Sarah G. “Solid Mentos Create Eruptions 5 Times Higher Compared to Crushed Mentos.” The Guilford Journal of Chemistry. Vol. 4: 15-9 (2010). 5 Alicia R., Sarah R., and Casey S. “Increasing Surface Area of Mentos Generally Causes Eruption Height to Decrease.” The Guilford Journal of Chemistry. Vol. 4: 20-4 (2010). 6 Rachel C. and Rachel M. “The Height of the Reaction Between Mentos and Diet Coke Decreases When the Shape of the Mento is Changed.” The Guilford Journal of Chemistry. Vol. 4: 25-9 (2010).


7

Grace I. and Amanda M. “High Surface Area Increases a Coke Mentos Eruption Height.” The Guilford Journal of Chemistry. Vol. 5: 48-50 (2011).


Loud Low Pitch Sounds Produce a 21% Increase in Eruption Height When Mixing Minty Mentos With Regular Coca Cola By: Jack D. and Kyle E. Summary: In our experiment, we used and electric guitar to play two different notes and two different volumes to see how eruption height of Mentos and Coke would change. Our control was a regular explosion, not affected by any noises, and compared it to different volumes and pitches. We found that when playing a loud noise with a low pitch, the explosion went 21% higher than the control and reached an average height of 182 centimeters. Our control reached and average height of 151 centimeters and was tied for second highest explosion with a loud high pitch sound. The quiet sounds we found to go roughly 20% lower than the control, with low pitch sound reaching an average of 123 centimeters and high pitch sounds reaching an average of 116 centimeters. Introduction: The mentos eruption is based off of thermodynamics, surface science, and the physics of explosions. There are two main ingredients that make the reaction work, potassium benzoate and aspartame. When the two mix, carbon dioxide quickly tries to get out of the bottle. Also, the surface area of the mentos affects the explosion, the more surface area, the more violent the reaction.i The roughness of the surface allows carbon dioxide bubbles to then form faster and create and larger explosion.ii Experimental Section: 1. Determine the amount of standard1 liter coke bottles required 2. For every bottle needed, get 3 minty mentos 3. Locate an electric guitar with an amplifier (Extension cord and trash bag recommended) 4. Place bottle of soda on ground near a tall wall. 5. Place amplifier roughly 1 foot away from bottle 6. Insert minty mentos in the geysers tube and make sure tube is prepared 7. Uncap the bottle and insert tube 8. Wait 5 seconds then play the desired note and volume for 3 seconds 9. Pull pin after note is playing for 1 second 10. Record height of soda base on where it hit the wall 11. Repeat steps 6-10 for all desired trials 12. Repeats steps 6-11 for all volumes and pitches


Results:

After experimentation, the data collected had certain distinguishable patterns. Most noticeable were the averages of the loud volume tests compared to the control and the low volume tests. The control average was 150.5 cm, as well as the loud volume/high note test average. The loud volume/low note test was significantly higher at 182 cm. Meanwhile, the soft volume/low note test only averaged at 122.5 cm, and the soft volume/high note test had an average of even less, only reaching 115.5 cm. Reviewing the data, one could say that the volume of the sound could be impacting the height of the Mentos. There is not enough reliable data to assume that the pitch of the note affected the height as well. However, the volume did seem to have a substantial effect on the height, as the first trial with the loud volume/low note test went 203 cm, while the first trial of the soft volume/low note was 133 cm. This 34% decrease shows a substantial change in height when the volume is altered. In addition, there was a 30% difference between the second trials of the low note tests as well. One can speculate that if more trials were carried out, the numbers would be in the same percentile.

Conclusion: After testing, there was shown that having a louder volume caused the Mentos to erupt higher. As far as this test was concerned, loud low pitch sounds created the largest


eruption. For future experiments, one variable should be tested at a time with greater precision and focus on that one variable, with the other variable being held a constant. Furthermore, the accuracy of the data in the recently performed experiment could be improved if more trials were run, but due to long setup and clean-up, as well as time restrictions, only two trials were able to be performed. It is believed that the increased power of the sound waves hitting the soda created vibrations in the soda, altering the conditions into which the Mentos were dropped. A fluid’s density, temperature, and pressure can change when sound vibrates that certain liquid.iii Any of these could have an effect on the height of the Mentos eruption. Temperature has clearly been shown before to have an effect on eruption height. An earlier test showed that warmer soda temperatures have resulted in higher eruptions.iv Furthermore, there are other studies proving that the pressure of the soda affects the height as well, proving less pressure inside lessens soda height. Any one of these variables could be looked into with more detail in more specific experiments in the future.v

Endnotes: i

Dr. T.S. Coffey. Diet Coke and Mentos: What is Really Behind this Physical Reaction? pg. 544

ii

Steven D. Spangler. Apparatus and Method for a Solid Catalyst and Fluid Dynamic Eruption Reaction. pg. 3 iii

A.B. Bhatia. Ultrasonic Absorption: An Introduction to the Theory of Sound Absorption and Dispersion in Gases, Liquids, and Solids. pg. 8 iv

Justin H. The Guilford Journal of Chemistry. Volume 1, pg.

v

Olivia S. Bronwyn R. The Guilford Journal of Chemistry. Volume 5, pgs, 51-53


Sprite Zero Erupts 7% Higher than Diet Coke in Comparison to Four Sodas By: Lucila K. and Lindsay L. Summary: When Mentos are added to carbonated beverages, the reaction is foam that rises at a high rate. It has been found that the potassium benzoate, aspartame and CO2 gas in carbonated beverages, when combined with the gelatin and gum Arabic in the Mentos, cause the reaction of the foam. 1 After testing four different kinds of soda to see which had the highest eruption, Sprite Zero had the highest eruption (224.2 cm) out of Diet Coke (210 cm), Coke (117.6 cm), and Sprite (117.6). This experiment was conducted to see which soda brand would erupt the highest when five Mentos were added to it. The results confirmed the data that Shore and Brown came up with. This study is a result of five averaged trials. Introduction: The Diet Coke and Mentos experiment has been tested many times before, and recently people have started to test the explosion height by testing different brands of soda. We found some of the same experiments previously done in The Guilford Journal of Chemistry. In one experiment conducted by Shore and Brown, they happened to use the same four sodas as we did. They found that Sprite Zero had the highest eruption, followed by Diet Coke, Sprite and Coke. 2 In an experiment done by, Lauren Cutuli, she found that Diet Tonic Water had the highest eruption, followed by Diet Coke, Diet Dr. Pepper, and Sprite Zero. 3 Musterer and Ruotolo, tested Fresca, Diet coke, Sprite Zero and Diet Pepsi and found that Diet Pepsi had the highest eruption, then Sprite Zero, Diet Coke, and then Fresca. 4 Also in an experiment done by Bruno E. and Asa D., they found that out of Diet Coke, Diet Pepsi, Sprite Zero, and Diet Canada Dry, Diet Pepsi had the highest eruption, followed by Diet Coke, and then Sprite Zero. They did not include Canada Dry in their results due to experimental error. 5

Experimental: 1. 2. 3. 4. 5. 6. 7. 8. 9. 10.

Collect 5, 12oz bottles of Sprite Zero, Diet coke, Sprite, Coke. Collect 12 packs of mint Mentos Collect one geyser tube Load geyser tube with five Mentos (Make sure pin is lodged and secure) Grab one bottle of Sprite Zero, open, and quickly screw geyser tube onto bottle nozzle. Place the bottle against a wall outside in an open space where the eruption can be measured Measure the mark that the explosion left on the wall and record in centimeters its height. Repeat steps 4-7 four more times Repeat steps 4-8 for the Diet Coke, Coke and Sprite Make a table/graph of the data and compare

Results:


After averaging the five trials, Sprite Zero had the highest eruption with 224.2 cm, while Diet Coke had the second highest eruption with 210cm and Coke and Sprite tied at last with an eruption of 117.6cm. Sprite Zero erupted 7% higher than Diet Coke, and 90% higher than Coke and Sprite.

250

The Effect of Different Soda Brands on Eruption Height

Height (cm)

200 150 100 50 0 Coke

Diet Coke

Sprite Zero

Sprite

Soda Type

Trials Soda Brand Sprite Zero Diet Coke Coke Sprite

1

2

3

Averages

4

5 245cm 210cm 77cm 105cm

203cm 210cm 133cm 112cm

203cm 210cm 133cm 140cm

230cm 203cm 105cm 119cm

240cm 217cm 140cm 112cm

224.2cm 210cm 117.6cm 117.6cm

Conclusion: Each kind of soda went through 5 trials to come up with these results. The bottles were all the same size, 12oz, and the same amount of Mentos was added to each bottle, five. Our results showed that Sprite Zero had the highest eruption of 224.2 cm. Next came the Diet Coke with 210cm, and finally, Sprite and Coke had the same average of 117.6cm. Our experiment complimented the Shore and Brown study in saying that the order of explosion height from highest to lowest was Sprite Zero, Diet Coke, Coke and Sprite. Unlike their experiment, however, we found that Sprite and Coke had the same average where as they found that Coke had a higher average than Sprite. Also, our experiment involved more trials. We had 5 trials per soda brand, where as they had 2 trials. By doing more trials, the validity of the


experiment increases. The other experiment showed a significant different between their two trials. This difference may be because there was an error in one of the trials. We may have gotten these results because of the ingredients in the sodas. For example, the two highest beverages were both low sugar drinks. Our data proved that Diet Coke is not the only soda that is able to produce a reaction when combined with Mentos. Our data also proved that Diet coke does not create the highest explosion when compared to Sprite Zero, which does produce the highest reaction. End Notes: 1. Dr. Brielmann. The Guilford Journal of Chemistry. Volume 1, pages 4-5 (2008). 2. Ethan Shore and Zack Brown. The Effect of Soda Type on the Height of Mentos Eruptions. The Guilford Journal of Chemistry. Volume 1, pages 4-5 (2008). 3. Lauren Cutuli. The Effect of Diet Drinks on the Height of a Mentos Eruption. The Guilford Journal of Chemistry. Volume 2, pages 36-37. (2009) 4. Musterer and Ruotolo. Diet Pepsi- Not Diet Coke- Results in the Highest Mentos Eruption When Compared to Other Diet Carbonated Drinks. The Guilford Journal of Chemistry. Volume 2, pages 12-14 (2009). 5. Bruno E. and Asa D. The Brand and Type of Diet Soda has a Direct Effect on the Average Eruption Height during Mentos Eruptions. The Guilford Journal of Chemistry. Volume 4, pages 61-64 (2011).


The Diet Coke and Mentos Eruption Using the Standard Geyser Tube Erupted 52.3% Higher than the Modified Nozzle Jackson I., Sonny C., Tim K.

Summary The purpose of the experiment was to decide whether a 1 liter Diet Coke bottle with or without a nozzle would make a larger eruption when paired with mentos. In an earlier experiment by Erin S. and Ashley B., three different nozzle sizes were used (small, large, medium). The medium sized nozzle ended up being optimum for height[i]. In an even earlier experiment by Gabriella Necklas and Kiersten Wall, it was concluded that to make the largest eruption, a smaller hole was needed[ii]. This absolutely contradicts the results of our experiment. During the trials conducted, it was found that the bottle with the nozzle that actually had a smaller opening than the bottle without a nozzle made a smaller eruption. In fact, the eruption from the bottle without the nozzle was, on average, 52.3% higher. Why the results between both experiments are so different is unknown.

Introduction The mentos eruption has been an experiment done a large amount of times. It is a reaction between carbonated beverage and mentos that causes the beverage to spray out of the container. Experiments in a 2006 edition episode of the television show Mythbusters suggested the chemicals responsible for the reaction are gum arabic and gelatine in the sweets, and caffeine, potassium benzoate and aspartame in the Coke. All of these ingredients help contribute to the eruption1. But there have been no rigorous scientific studies of the reaction until now. Experiments have been conducted using caffeinefree diet coke, which ended up showing no difference in the height, which suggested that the caffeine did not affect the eruption. "Water molecules like to be next to other water molecules, so basically anything that you drop into the soda that disrupts the network of water molecules can act as a growth site for bubbles," Coffey told New Scientist. "And if you have rough candy with a high ratio of surface area to volume, then there's more places for the bubbles to go. This was one idea of what made this exciting eruption from these two substances2. A paper by Tonya Coffey, a physicist at Appalachian State University in Boone, North Carolina goes into detail on the reasons and physics behind the reaction. Coffey found that the rough surface of the mentos helps speed up the reaction. Coffey also found that the

1

"Mythbusters: Diet Coke and Mentos". TV.com. Retrieved 2012-10-3.

2

American Journal of Physics, DOI: 10.1119/1.2888546


aspartame in diet soda lowers the surface tension and causes a larger reaction, but that caffeine does not speed up the reaction3.

Experimental Section In order to achieve accurate results, the same procedure was followed for each trial. The steps are as follows: 1) Gather materials 2) Place platform near wall on slight angle 3) Place Coke bottle on platform 4) Take original geyser tube and fill, from the bottom, with 4 Mentos 5) Place pin to keep Mentos from falling out 6) Unscrew Coke bottle and begin timing 7) Attach tube to Coke, making sure to keep the pin in place 8) After a duration of 15 seconds from the opening of the bottle, release pin and continue to hold the bottle 9) Record data 10) Repeat steps 2-9 twice more with the new bottles of Coke 11) Repeat steps 2-9 three more times using the alternate nozzle

Results With all of the research and experimentation conducted, the results that were gathered were very informative. (You may refer to the graphs on the final page for a visual of the information.) With each set of bottles - the three without the nozzle and the three with - three trials were run. In the Coke bottles with the standard geyser, all of the runs went very smoothly. All of the results were similar. The first bottle’s eruption went 616 cm, the second went 630 cm, and the third went 588 cm. On average, the height of the geyser went 611.3 cm. The height of the nozzled geysers was significantly less. On average, their height was 319.7 cm. Bottle one went 273 cm, number two went 266 cm, but bottle three 3

Coffey, Tonya Shea (June 2008). "Diet Coke and Mentos: What is really behind this physical reaction?". American Journal of Physics 76 (6): 551–557. doi:10.1119/1.2888546


went 420 cm. One of the faults of the nozzle was that the pressure was so great, that the tip actually came off, or the soda shot out the sides rather than the top, or a combination of both. In both bottle one and two, there was some technical difficulty. For both of the first two trials, there was difficulty with the tube. In the first, the tube itself was not attached to the Coke correctly. In the second, the glue tip detached itself. If the experiment was to be repeated, it would be made sure that the tip was securely attached to the tube.

Conclusion In our experiment, it was concluded that the 1 liter bottle of Diet Coke without a nozzle made a significantly larger eruption than the 1 liter bottle of Diet Coke with a nozzle. However, the results may have looked this way partly because of the Diet Coke spurting through the sides of the nozzle during all three trials. During the first trial, the Diet coke without the nozzle erupted 616 centimeters (88 bricks). The bottle with the nozzle on it erupted 273 centimeters (39 bricks). This shows that the bottle without the nozzle erupted 44.3% higher than the bottle with the nozzle on. In the second trial, the bottle without the nozzle erupted 630 centimeters (90 bricks). The bottle with the nozzle on it erupted 266 centimeters (38 bricks). This means that the bottle without the nozzle erupted 42.2% higher than the bottle with the nozzle on it. In the third and final trial, the bottle without the nozzle erupted 588 centimeters (84 bricks). The Diet Coke bottle with the nozzle erupted 420 centimeters (60 bricks). This means that the bottle without the nozzle on it erupted 71.4% higher than the bottle with the nozzle on it. Averaging all the numbers together, the bottle without the nozzle erupted 52.3% higher than the bottle with the nozzle on it. Keep in mind that the number of mentos placed in each bottle was kept constant to assure that the results were valid. Of course, on closer inspection, there were probably things that could have been done and should have done differently in the experiment. For example, if the experiment were to be done again, the nozzle on the Diet coke bottle would be more securely tightened so that soda would not end up all squirting out of the sides rather than the top. It was also observed that from the time that the cap was taken off of the bottle to the time that the mentos were actually dropped into the soda lasted several seconds. If the experiment were to be repeated again, it might be beneficial to shorten the time frame of this so as to reduce the amount of carbonation lost from the Diet Coke. All in all, it was determined that the Coke bottle with the original tube was much more proactive in the height of the geyser compared to the modified nozzle.

Endnotes: [i]Erin S and Ashley B, Guilford Journal of Chemistry Volume 4 (2010-2011) [ii]Gabriella Necklas and Kiersten Wall, Guilford Journal of Chemistry Volume 1 (2007-2008)

.



Minimizing the CO2 Lost During the Application of the Geyser Tube Increases the Pressure within the Bottle but Decreases the Height by 8.54% By: Kate V. and Sophie K. Summary Mentos and Diet Coke are a scientific match made in heaven; when these minty treats are dropped into diet soda, it causes an eruption into the air. Many different experiments have covered almost every aspect of this eruption and the concept has been toyed with for years.1 Our particular experiment explores the idea that if the amount of CO2 lost during the application of the geyser tube, a device used to drop Mentos into soda bottles through the pull of a pin, was decreased, the height would increase. This experiment was inspired by a previous one, which focused on delaying the time between the opening of the bottle and the drop of the Mentos. We attempted to engineer a system that would allow the Mentos to enter the bottle without releasing any CO2 from the bottle and were forced to overcome several obstacles. In the end, a system that included rubber gloves, duct tape and a rubber disc was shaped. We used the rubber glove and duct tape to contain the CO2 that was released at the opening of the cap, and were able to create a substitute cap. In addition to the bottle, the geyser tube was air tight due to a piece of duct tape covering its nozzle. Therefore, we were able to drop the Mentos into the bottle with limited CO2 escaping. In our control, we opened the bottle and screwed on the geyser tube at a normal pace allowing a fair amount of CO2 to escape. The maximum height achieved by this was 52 blocks (225.5 cm), the minimum was 35 blocks (192.5 cm), and the average for this was 42.33 blocks (232.815 cm). Contradictory to the initial intention of the experiment, the bottles with our rubber glove and disc system had a lower average height by 8.54%. The maximum height for this one was 49 blocks (269.5), the minimum was 35 blocks (192.5 cm), and the average was 39 blocks (214.5 cm).Although the experiment showed that the coke went a lower height, we did observe that because of the higher CO2 levels, the coke was much for pressurized. Introduction The diet soda and Mentos eruption has been a common household and classroom experiment for all ages since 1999, when it first premiered on the David Letterman Show.2 In recent years, people all over the world have enjoyed both participating in and watching this scientific phenomenon via an episode of Mythbusters, numerous videos on YouTube, and even Chemistry classes throughout the nation.3 In order to create an eruption, Mentos are dropped into a newly opened bottle of diet soda. There are five major ingredients that make Diet Coke and mint flavored Mentos ideal. Diet Coke contains caffeine, potassium benzoate, and aspartame; while Mentos contains gum arabic and gelatin.4 A major muse for our experiment was a previous report from last year, by Olivia Schultes and Bronwyn Reeves. They increased the time between the bottle opening and the dropping of the Mentos, and discovered that it decreased the height.5 Through this conclusion, we were able to assume that the opposite was true: that decreasing the amount of CO2 released would increase the height. We wanted concrete proof, and decided to test this theory.

Materials


1. Six diet coke (16oz) bottles 2. Four packs of mint Mentos 3. Three clear large rubber gloves 4. One roll of duct tape 5. One 2” rubber disc 6. One pair of scissors 7. One geyser tube Experimental Procedure 1. Set up an area near a wall on a surface that is at a 20 degree angle to the wall 2. Put on goggles 3. Put nine Mentos into the geyser tube 4. Put a 1” strip off duct tape over the hole of the geyser tube 5. Tie off each of the fingers in the gloves 6. Take out a settled coke bottle 7. Place the 2” rubber disc on top of the cap 8. Place the glove around the top of the diet coke 9. Seal off the glove with duct tape around the bottle 10. Unscrew the cap of the coke bottle through the glove 11. Push the cap to the side letting it sit on the edges of the glove 12. Have one partner hold down the 2” rubber disc as the other cuts the rubber glove around the 2” rubber disc 13. Remove the remainder of the rubber glove that was covering the 2” rubber disc 14. Continue to keep pressure on the rubber disc 15. Place the bottle on the angled surface 16. Have one partner hold the bottle and rubber disc covering the cap 17. Have the other partner place the geyser tube on top of the rubber disc 18. Quickly pull out the rubber disc then slide and screw the geyser tube onto the coke bottle 19. Have one partner pull off the duct tape covering the geyser tube 20. Pull the red string in the geyser tube and hold the bottle Results Although there was little consistency in the following results, it did show that the control had some heights that were much higher than those where variables were altered in the experiment. The collected data showed that the average for height reached was slightly less than in the control. On the other hand, a big difference between the control and experiments with the altered variable was the increased pressure in the altered experiment. However, we were unable to calculate that as a measurement. Control: Trial 1 Trial 2 Trial 3 41 blocks (225.5 cm) 35 blocks (192.5cm) 52 blocks (286 cm) Average: 42.33 blocks (232.815 cm) Experiment: Trial 1 Trial 2 Trial 3 33 blocks (181.5 cm) 35 blocks (192.5 cm) 49 blocks (269.5 cm) Average: 39 blocks (214.5 cm) Conclusion


Previously, an experiment tested the idea that the “amount of time between opening a bottle of Diet Coke and the Mentos release affects the size of the eruption” and proved that delaying the time between opening and actually dispensing the Mentos decreased the height of the eruption, but not by a significant amount.6 The data collected in this most recent experiment added on to the prior data, and reflected the other side of the spectrum. The past experiment’s data suggested that, since the CO2 released decreased the height, that decreasing the CO2 released would increase the height. However, contradictory to past figures, the height of the eruptions actually decreased through this new adjustment. It was discovered though, that the pressure at the time of the eruption, and the power that each eruption had. In one instance, even though the geyser tube was screwed on tight, and there was someone holding it in place, when the soda erupted, the geyser tube shot off the bottle and caused the eruption to hit two different places on the wall. While this experiment yielded interesting results, and was built upon a previous report, there are multiple suggested experiments that would be follow-ups, and improve the data collected. One possible improvement to the glove system created in this experiment would be to find a way to calculate the pressure, and record the specific increase. Another improvement would be to make sure that the eruptions hit the wall, but not prematurely. A possible flaw in the experiment that was just completed was that, while the eruptions should have gone higher, it is possible that they hit the wall in such a way that prevented the soda from continuing to climb. Finally, a third possible follow-up would be to simply focus on the time, instead of focusing on the CO2 released. If an experiment were to hone in on just decreasing time, the results may vary from this experiment, which aimed solely to change the amount of CO2 expelled. 1

Professor Tanya Shea Coffey, Diet Coke and Mentos; What is really behind this Physical Reaction?, Page 551 (2008). 2

Ibid, see paragraph 1

3

Ibid, see paragraph 2

4

Ibid, see paragraph 1

5

The Amount of Time Between Opening a Bottle of Diet Coke and the Mentos Release Affects the Size of the Eruption. Olivia Schultes and Bronwyn Reeves, The Guilford Journal of Chemistry, 2011-2012, pp. 51-53. 6

Ibid, see page 52



Mentos Heated to 30º Celsius Cause an Eruption of Diet Pepsi 32.8% Higher Than Mentos at 25º Celsius. Cole H., Sean H. and Logan F. I. SUMMARY The “mentos eruption” is an experiment in which mentos are placed in a carbonated beverage, usually diet coke or diet pepsi. An explosive explosion occurs, causing the beverage to shoot out of the bottle. This experiment sought to discover the effect of heating mint mentos on the height of a diet pepsi eruption. Although previous research has been completed in this field, much of the data is unreliable due to an insufficient number of trials. In general, however, previous researchers have found that heating mentos increases the height of the eruption. The data collected in this experiment showed that heating mentos to 30 C increased the height of a diet pepsi explosion by 32.8% compared to 25 C room temperature mentos. Four trials were completed for each temperature mentos, and the height of explosion in bricks, the time between the cap being opened and the geyser tube pin being removed, and the mass lost were all recorded. The height was first recorded in bricks, and then converted to centimeters, where 1 brick is equivalent to 7 centimeters. The average height reached by the room temperature mentos was 234.5 cm, while the heated mentos created an explosion reaching an average of 311.5 cm. The average mass lost by room temperature mentos was 313.85 grams, while it was 324.05 grams for the heated mentos. This is a change of 3.25%. The average time between the cap being removed on the soda and the mentos being released was 15.2 seconds for room temperature mentos and 14.9 seconds for heated mentos. Based on these results, it can be hypothesized that the height of the explosion is a linear function of the temperature of the mentos. II. INTRODUCTION The diet pepsi and mentos experiment is an experiment that is quickly growing in popularity amongst the science community.i First featured on television on the David Lettermen Show in 1999, the experiment was later conducted on the Discovery Channel’s Mythbusters in 2006.ii The diet pepsi and mentos lab is conducted by dropping several mentos into a freshly opened bottle of diet pepsi. It is essential to insert the mentos into the soda as soon as possible in order to maintain a high carbonation level and keep the soda from becoming flat. The dropping of the mentos results in a large, foamy eruption of soda. The reason for this is a reaction that occurs between the potassium benzoate, aspartame, and CO2 in the soda and the gum arabic and gelatin in the mentos.iii However, this is not a chemical reaction as one might assume; it is a


physical reaction for when the mentos enter the diet pepsi they are covered in bubbles which, in turn, displace the cola and shoot it out of the bottle.iv A rather interesting experiment has proven a common misconception incorrect. While diet coke and diet pepsi are oftentimes considered to be virtually synonymous, Musterer and Ruotolo proved with their experiment that eruptions with diet pepsi are more than two times taller than eruptions with diet coke.v A lab conducted by Rachel Cutler and Emma Smith directly correlates to the experiment conducted. They tested the effect of heating mentos on the height of the eruption. According to their results, increasing the temperature of the mentos from 300K to 313K resulted in, approximately, a 567% increase in eruption height.vi The general consensus remains that heating mentos will increase the height of a diet pepsi eruption; however this study presents solidified evidence through the use of more trials and a greater number of constants. III. EXPERIMENTAL 1. Obtain eight 250 mL Diet Pepsi bottles, a minimum of 44 mint mentos, safety goggles, and a geyser tube. 2. For room temperature mentos trials, record the temperature of two mentos by splitting them in half and inserting thermometer into filling. Record temperature and average the two. 3. Fill geyser tube with five mentos. 4. Position bottle on a slight angle facing a brick wall. 5. As soon as cap on soda is opened, start timer and screw on geyser tube. 6. At 15 seconds, pull the pin of the geyser tube and back away. 7. Record the number of bricks reached by the soda from the top of the tube. 8. In permanent marker, write the trial number on the soda bottle after eruption. 9. Repeat steps 3-8 three more times. 10. Once all trials for room temperature mentos are completed; use an electronic scale to measure the original mass, in grams, of the soda and then the mass after the eruption to determine the mass lost. 11. For heated mentos trials, place 5 mentos at a time into a microwave safe dish and heat until 30ď‚° C, approximately 30 seconds. 12. Using the heated mentos, repeat steps 3-8 from the control trials four times. 13. After explosions are complete, measure the mass of the sodas and subtract the weight from the original weight of an unused bottle of diet pepsi. 14. Convert height of explosion in bricks to centimeters, where 1 brick is equivalent to 7 cm.


IV. RESULTS The experiment compared the height of diet pepsi eruptions between room temperature mentos (25ď‚° C) and heated mentos (30ď‚° C). Figure 1 illustrates the impact of mentos temperature on the height of the explosion in the form of the bar graph. For the room temperature mentos, the average time between the opening of the soda bottle and the pin being pulled on the geyser tube was 15.2 seconds. The average height achieved was 234.5 cm above the top of the geyser tube and the average mass lost was 313.85 g. For the heated mentos, the average timing between the opening of the soda and the pulling of the pin was 14.9 seconds. The average height reached was 311.5 cm, and the average mass lost was 324.05 g. These results show that there was, on average, an increase of 32.8% in the height of the eruption when using heated mentos, compared to the room temperature ones. Data Tables of Actual Results Room Temperature Mentos Trial

Time between Opening of Cap and Pin being Pulled on Geyser Tube (seconds)

Height of Explosion (centimeters)

1

14.9

217.0

313.40

2

15.9

203.0

311.90

3

15.0

273.0

311.20

4 AVERAGE

15.0 15.2

245.0 234.5

318.90 313.85

Trial

Heated Mentos Time between Opening of Height of Explosion Cap and Pin being (centimeters) Pulled on Geyser Tube (seconds)

Mass Lost (grams)

Mass Lost (grams)

1

14.3

294.0

322.80

2

15.1

315.0

328.30

3

15.0

301.0

320.20

4 AVERAGE

15.2 14.9

336.0 311.5

324.90 324.05

Data Table of Predicted Eruption Heights based on Temperature of Mentos and Hackett-Horton Law


FIGURE 1

Predicted Height of Eruptions as a Function of Mentos Temperature using Hackett-Horton Law: H=15.4t-150.5 Temperature 25 30 35 40 45 50 55 60 65 70 75 80 85 of Mentos (C) Height of Eruption (cm)

234.5

311.5

388.5

465.5

542.5

619.5

696.5

773.5

850.5

927.5

1004.5

1081.5

1158.5

Heating Mentos to 30° C Increases the Height of a Diet Pepsi Eruption by 32.8% compared to 25° C Mentos Eruption Height (centimeters)

400 336

350 300 250

273

217

311.5

301

315

294

245

234.5

203

200

25° Celcius Mentos

150

30° Celcius Mentos

100 50 0

FIGURE 2

Trial 1

Trial 2

Trial 3

Trial

Trial 4

Average


Predicted Height of Eruptions as a Fucntion of Mentos Temperature using Hackett-Horton Law: H=15.4t-150.5 1400

Height of Eruption (cm)

1200

1158.5 1081.5

1004.5

1000 927.5 850.5

800

773.5 696.5 Height of Eruption

619.5

600 542.5 465.5 400

388.5 311.5

200

234.5

0 25° C 30° C 35° C 40° C 45° C 50° C 55°C

60°C

65°C

70°C

75°C 80° C 85° C

Temperature of Mentos (°C) VI. CONCLUSION The experiment has demonstrated that heating mentos to 30 C will increase the height of an eruption by an average of 77 bricks or 32.8%. Additionally, the mass lost was recorded compared to the original mass of 525 g. Compared to the room temperature mentos, the heated mentos constituted a larger mass lost, at 3.25%. The data collected can be considered valid, as other research in this field has supported previous findings. As stated beforehand, Cutler and Smith found that heating mentos to 40 C increased the height of the eruption. However, the validity of the majority of previous research on the correlation of heating mentos and the height of the explosion is questionable. All previous conclusions have been based on a maximum of two trials, increasing the possible percentage error. In order to lessen the chances of errors, four trials for each temperature mentos were completed, and any questionable results were redone. In addition, the timing of the explosion was kept, on average, to within 0.3 seconds of each other. However, a few possible errors may have occurred during the experiment. Some experimental error could have occurred in regard to the heated mentos as the temperature was taken just as they exited the microwave and may have cooled down slightly by the time they were in the cannon and being dropped into the diet pepsi. Other factors could include wind speed and direction and the angle at which the soda bottle was placed. In the future, a 20 launch angle would be recommended as a constant. Next, if any of the bottles were


shaken unknowingly, opening the bottles would release a greater amount of carbon dioxide compared to unshaken bottles. To improve the experiment, an indoor launch site would benefit the results as wind would not be a factor, and a more consistent time between the heating and dropping of the mentos would occur. Despite these factors, the data collected is still thought to be accurate because of the closeness in range of the data points and the amount of data collected. This both supports and solidifies the hypothesis that heating mentos increases the height of an eruption. One of the major discoveries related to the experiment was a correlation between mentos temperature and eruption height. By creating a linear function, a prediction could be made for eruption heights with untested heats of mentos. By using the known data points, and point-slope form, the function was determined to be H=15.4t-150.5, where H is the eruption height in centimeters, and t is the temperature of the mentos in degrees Celsius. This function was christened the Hackett-Horton Law. This ability to predict eruption heights as a function of mentos temperatures would allow for calculating hypothetical eruptions with mentos at temperatures so high they would deform. Also, with additional data points, a quadratic formula could be formed to show eruption heights for mentos at extremely low temperatures. However, this would also eventually fail, as at a temperature of -273.5 C, they would reach absolute zero. A follow up experiment would be determining at which mentos temperature the HackettHorton Law fails, when the structural fatigue become too great and the mentos melt. In addition to heating mentos to the point of structural failure, mentos could be frozen using dry ice, to determine when they crack. Overall, this experiment successfully indicated that heating mentos to 30 C from 25 C increases the height of a diet pepsi eruption by an average of 77 cm, or 32.8%.


Endnotes: i

Jacob H, Ben B, and Colton S. The Effect of Different Sodas on the Height of a Soda and Mentos Eruption. Guilford Journal of Chemistry, Volume 5, Page 4 (2011). ii Juandiego C. Manipulating the Surface of Mentos: The Resulting Diet Coke and Mentos Explosion Height will Increase if the Increased Surface Roughness is Greater Than the Losses of Mass and Gum Arabic. Guilford Journal of Chemistry, Volume 5, Page 62 (2011). iii Coffey, Tonya. Diet Coke and Mentos: What is Really behind this Physical Reaction? Am. J. Phys, Vol. 76, No. 6, Pages 551-557 (2008). iv Anny Y. Mint Mentos Erupt 165 Higher Than Strawberry Mentos and 55% Higher Than Green Apple Mentos with Diet Coke. Guilford Journal of Chemistry, Volume 5, Page 11 (2011). v Angelise Musterer and Lindsay Ruotolo. Diet Pepsi –Not Diet Coke – Produces High Results in Mentos Eruption When Compared to Other Diet Carbonated Drinks. Guilford Journal of Chemistry, Volume 2, Page 12 (2008). vi Rachel Cutler and Emma Smith. Mentos Eruptions are increased by heating or Cooling the Mints. Guilford Journal of Chemistry, Volume 1, Page 7 (2007).


Amount of Carbonation Matters - Height of Eruption Decreases 80% When Diet Coke Bottles Opened 48 Hours Prior to Eruption By Jaimie C and Becca W Summary: This experiment tested how the time between opening a diet coke and performing the explosion affects how large the explosion is. We hypothesized that the longer the time span between opening the soda and releasing the Mentos, the smaller the explosion because of the decreased amount of carbon dioxide. To test the hypothesis, we used five different amounts of time, forty hours, twenty four hours, ten minutes, five minutes, and then a constant, which we immediately opened before the explosion. The average height of the explosion after forty eight hours was three bricks, after twenty four hours was seven bricks, after ten minutes was fifty bricks, after five minutes was thirty eight bricks, and immediately after was forty eight bricks. Introduction: The diet coke and Mentos experiment was previously performed on the 2006 Mythbuster’s episode and was first introduced in 1999 on the David Letterman show³. When a soda bottle is opened, the carbon dioxide stays in the bottle for the most part, unless an object is dropped in it, the soda is shaken, or the liquid is poured out4. When the gas is in the bottle, it cannot expand to form more bubbles4. When a Mento’s is dropped in a soda having a very rough surface, it causes nucleation to occur and growth of carbon dioxide bubbles5. This gas expansion causes the soda to explode out of the bottle5. According to the Mythbuster’s episode, diet coke is the most reactive soda to use in this experiment because it contains caffeine, aspartame, and potassium benzoate³. Diet coke also works best because it does not have large sugar molecules². Because of this, carbon dioxide is released faster, and nucleation is not slowed down². The original Mentos lab experiment is performed by dropping a few Mentos into a freshly opened bottle of diet coke, resulting in an eruption³. Olivia S and Bronyn R previously did an experiment almost identical to this study, measuring the effects of the level of carbonation of the soda. They tested this by using three different amounts of time, thirty seconds, one minute, and five minutes¹. The report’s average eruption height for thirty seconds was 423 cm, one minute was


364 cm, and five minutes was 329 cmยน. They were able to make the conclusion that when a diet coke is left unopened for a lengthened amount of time, the eruption will be more explosiveยน. Experimental: 1. Purchase 10 bottles of Diet Coke and 4 packs of regular mint Mentos 2. Open the Diet Coke bottles prior to experiment at designated time intervals, 2 bottles per each time interval (48 hrs, 24 hrs, 10 min, 5 min, and immediate) 3. Place a board near a wall where the experiment will be conducted 4. Fill a geyser tube with 6 Mentos and screw it on top of the first Diet Coke bottle 5. Pull the pin to trigger eruption 6. Measure the height of the eruption and record the data (helpful to measure where the soda reached, based on markings on wall) 7. Repeat steps 4-6 with all 10 sodas 8. Compile the data into a table Results: Time Soda Open (min)

Height of Eruption (cm) First Trial Second Trial Average

0.5 min

335 cm

330 cm

333 cm

1 min

286 cm

286 cm

286 cm

1 min

350 cm

322 cm

336 cm

5 min

259 cm

259 cm

259 cm

5 min

210 cm

322 cm

266 cm

10 min

350 cm

350 cm

350 cm

1440 min (24 hrs)

70 cm

27 cm

49 cm

2880 min (48 hrs)

27 cm

27 cm

27 cm

*Blue Ink represents data from the Schultes and Reeve experiment


Height of Eruption (cm)

Effect of Carbonation on Eruption Height

Time Bottles Opened (min)

Conclusion: This experiment explored the effect of carbonation on the height of the eruption. The data proves that the longer the bottle is opened, diffusing the carbon dioxide, the smaller the eruption will be because ample carbon dioxide is necessary for a successful eruption4. There was an 80% decrease in the height of the eruption from the one minute eruption and the forty-eight hour eruption. Our data also supports the conclusion made in the Schultes and Reeve experiment. The longer the bottle is opened prior to the release of the Mentos, the smaller the eruption. The results make sense because the height generally decreases as the amount of time the bottle is opened decreases. In both ten minute trials, the height was significantly greater than what was expected, so in a follow up experiment, that time increment would need to be assessed. Also, to solidify our conclusion, adding more trials per each time increment and adding more time increments would be helpful. For example, there could be trials for one, two, three, four, and five hours to close the gap between the twenty-four hour trial and the ten minute trial. However, from the data we collected and compared with previous experiments, the amount of time the bottle is opened to diffuse the carbon dioxide is definitely correlated with the height of the eruption; less carbonation results in a smaller eruption.


References:

1. The Amount of Time between Opening a Bottle of Diet Coke and the Mentos Release Affects the Size of the Eruption by Olivia S and Bronwyn R. Guilford J. Chem., 2011-2012, pp. 51-53. 2. Chemistry for Kids Taught by Rand Mahoney and Greg Bowers. Mt. Diablo Silverado Council- Pow Wow 2008 (Jan. 19, 2008). 3. Diet Coke and Mentos: What is really behind this physical reaction? By Tonya Shea Coffey Am. J. Phys. 2008, volume 76, number 6, pp. 551-557. 4. Fun in the Sun with Science by Susan Weiss. The Broward Education Foundation. 5. World Record for Mentos- Diet Coke Geyser Eruptions by Susan W. Kieffer. Geology In Motion. June 16, 2010.


Coated Fruit Mentos Produce an Eruption Height 35.9% Greater than Those with Removed Coating Report by: Joe I. Tested by: Isaac A. Chris C. and Joe I. Summary: Diet-Coke and Mentos are two common household indulgences and also provide a common classroom experiment, as they produce an eruption when in contact with each-other. A multitude of experiments can be configured based upon these two ingredients, and the subject matter of this experiment had been whether or not the candy surface of Mentos affected eruption height. To briefly depict the experiment, things used had been regular Fruit Mentos without alterations as a control, and then sanded Mentos, with no candy-coating, as the test. Constants had been Diet-Coke bottle size (12oz.), 15 seconds between opening the bottle and putting Mentos in, five Mentos for each drop, four trials per test, scale used, system used to measure (SI), type of beverage (Diet-Coke), sand paper, and type of Mentos (fruit). This test was initialized in order to find if nucleation was key, or if the candy-coat was a necessity. The results returned data that showed the unaffected Mentos went 224cm in height, 35.9% higher on average, than the sanded Mentos which went 143.5cm. Also recorded was the mass of the beverage after each trial. The starting mass for each was 353.5g (this is without the mass of the bottle which is 29g), and the average ending mass had been 132.6g (losing 220.9g) for the control and 145.075g (losing 208.4g) for the sanded Mentos, showing that the normal Mentos lost the most mass by 5.7%. Introduction: The constantly discussed investigation of Mentos candy and Diet-Coke has been a widespread test throughout the entirety of the world, ranging throughout each grade and even into professional studies. Thus, because of its recent rise to fame, an abundance of studies have been produced and reproduced, yet the reason for the eruption still remains a heavily debated mystery. A plethora of various tests have been recorded as well, yet common conclusions point mainly to the surface of the Mentos as an integral factor. Since the test was popularized by scientist Lee Mareck in 1999 on the David Letterman show, the idea of nucleation has been a key factor. Nucleation, in this context, can be defined as when carbonated bubbles form in pockets of a rough solid (Mentos).1 Mareck had claimed this to be the sole reason for the explosion; the fact that the Mentos broke the liquid surface tension and had bubbles form in nucleation sights after


the liquid was displaced. This too was supported by the Mythbusters team, as they stated that the wax coating on Fruit Mentos inhibited a successful eruption, yet much other research contradicts this, including the experiment discussed in this report.2 In the Guilford Journal of Chemistry Vol. 1, an investigation by Carly C. and Jenn A. showed results that unaffected Mentos reached an average height of 230cm, while Mentos without this coating went approximately 200cm lower, as they reached a height of 33.33cm.3 Jenna P. of Journal Vol. 5 had too pursued a similar experiment and concluded that, in fact, coating positively affected eruption height.4 In a more professional experiment by Professor Tonya Shea Coffey of Appalachian State University, surface roughness was tested using a scanning electronic microscope (SEM). Wint-o-Green Lifesavers had shown a surface roughness of 2630nm while fruit flavored Mentos only showed a surface roughness of 443nm, yet the results stand in contradiction to the theorizations of Mythbusters. The rough Wint-o-Green Lifesaver had only went 7ft high and lost a mass of 1430g when dropped in a 2L Diet-Coke, while the smoother Fruit Mentos went 17.8ft high, while losing a mass of 1440g. This test also reported that contributing chemicals in the experiment are gum Arabic in the Mentos, and caffeine, potassium benzoate, aspartame in Diet-Coke.5 The investigation of focus in this paper had reported that, on average, the regular Mentos reached a height of 224cm, while the sanded down, uncoated Mentos reached an average height of 143.5cm. Experimental Section: This experiment had been to find if the manipulation of the surface of the Mentos would result in different eruption intensities. The control trial had been Mentos with no modifications, while the test had been Mentos sanded down to a point where no coating was left. Constants had been 12oz. bottle size, 15 seconds between opening the bottle and dropping Mentos in, five Mentos for each drop, four trials per test, scale used, system used to measure (SI), type of beverage (Diet-Coke), the sand paper used, and type of Mentos (fruit). The independent or manipulated variable had been type of Mentos, while the dependent had been eruption intensity, measured by the height of the eruption and mass lost. There are few safety concerns other than wearing goggles at all times throughout the duration of the test, and to not wear nice clothing, as it may get dirty. Materials used were: 

Fruit Mentos (at least 40)



A Geyser Tube


12oz. Diet-Coke bottles (at least 8)

A stopwatch

A level environment with little distractions

A heavy-duty mass scale set to grams

Sandpaper (Grade does not matter so long as it can remove coat)

Pencil and Paper

Safety goggles (number dependent on number of people participating)

The steps, or procedure, in order to replicate this test are as follows: 1. Procure the items above 2. Find a proper location, preferably next to a wall so that height can be easily seen from splashes 3. Measure mass of all full bottles and an empty bottle 4. Begin testing by making sure bottle is on level ground, next to wall, and prepare stopwatch 5. Place goggles on and put five regular Mentos in Geyser Tube 6. Simultaneously begin stopwatch and unscrew cap of bottle 7. Immediately after removal of cap, screw in Geyser Tube and prepare to pull string and release Mentos 8. At fifteen seconds pull the string and drop Mentos into Diet-Coke 9. Record height reached in centimeters and label bottle according to trial 10. Repeat steps 5-9 in the same spot 3 more times 11. Proceed to sand 5 Mentos so that the candy-coat is ENTIRELY removed 12. Repeat Steps 5-9, this time using sanded Mentos 13. Repeat steps 11 and 12 three more times 14. Measure mass of each bottle and record in grams after removing Mentos from the bottle 15. Subtract empty bottle mass from each trial 16. Subtract the mass from the trials from the full bottle mass to find mass lost 17. Then graph the results Error Analysis: Throughout the testing, human errors arose as expected in any other scientific experiment. The main flaws had been that the bottle may not have always been perpendicular to


the ground, the ground was uneven, the candy-coat may not have been completely removed, and at times the soda began to fizz before the addition of Mentos. Had there been a surplus of materials, some of these could have been corrected. Although these factors only slightly altered the results, they still reduce the accuracy and precision of results. In order to form a more perfect analysis of the topic, each error must be overcome and corrected. If the bottle is not perpendicular to the ground then the eruption will be on an angle, reducing overall height. This idea is also true for a bottle that is on uneven ground, because the bottle will not be correctly aligned. If the candy-coat is not completely removed, then it will too affect eruption height because the coat is vital to eruptions. Lastly, one must avoid the shaking of the bottles because it will result in the premature eruption of the beverage, resulting in mass lost prior to test. If these are corrected, more accurate results can be attained. Results: The experiment at hand had produced results that illustrated regular Mentos dominance over those without a candy-coat. Each trial, of both mass and height, produced results in which the eruption strength of unaffected Mentos was greater. The trials for the control height had been 224cm, 252cm, 224cm, and 196cm with an average of 224cm, which was 35.9% higher than the average of the sanded candies. These sanded Mentos went 133cm, 126cm, 196cm, and 119cm averaging to 143.5cm. The averages for the mass lost proved to be closer, yet still the candycoated Mentos still came out with more mass lost. The masses for the control trials had been 229.7g lost, 218.3g lost, 204.5g lost, and 231.1g lost averaging out to 220.9g lost. The masses for the sanded Mentos trials had been 204.9g, 204.9g, 220.7g, and 203g with an average of 208.4g. The sanded Mentos trials had a 5.7% decrease in mass lost from the control. When gathering these results, an observation had been made that the coating of the Mentos began to react quite suddenly when it came into contact with the Diet-Coke, even a single drop would deteriorate the exterior color. The coating was strongly affected by the carbonated beverage, while the sanded Mentos looked rather the same. Another integral observation had been that the sanded Mentos appeared rougher through both visual and tactile observation, yet failed to reach the same height as the candy-coated Mentos. Although this observation was made without evidence other than the five senses, it may still prove to be very important.


Height of Eruptions in Centimeters 300

Height in Centimeters

250 252 200

224

224 196

196

150 100

224

133

Control

143.5

126

Sanded

119

50 0 Trial 1

Trial 2

Trial 3

Trial 4

Average

Trial # and Average

Mass Lost After Eruptions In Grams

240

230 Mass Lost in Grams

231.1 220

229.7 220.7

220.9

218.3

210

Control 200

208.4 204.9

204.9

204.5

203

190

180 Trial 1

Trial 2

Trial 3

Trial 4

Average

Trial # and Average

Conclusion: Our Results had been gathered with only minor errors thus one can conclude that they are, in fact, correct. They too align with previous experiments in this art; therefore they are a reliable reference in the quest for answers. The results, once again, had proven that a candy-coat was a definite necessity for optimum eruption intensity, as the control Mentos went 35.9% higher, and the control lost 5.7% more mass. These results stand in dispute of the Mythbusters experiment and that of Lee Mareck, who stated that nucleation, was the sole factor and that the wax coating of Fruit Mentos would inhibit a successful eruption. In contrast the wax, candy-coat proved itself to be quite a requirement for a successful eruption. The sanded Mentos, as

Sanded


observed, had been rougher as well which provides more possible sites for nucleation, yet they had not gone nearly as high as the control Mentos. Although the gathered data disputes that of the television program Mythbusters, and the studies of Lee Mareck, it runs parallel to the gathered data of other Guilford High School students who pursued similar investigations. A possible explanation for such results is that an integral ingredient in a Diet-Coke and Mentos eruption lies within the coat, this is not only supported by the data gathered, but by observation as well, as it was noted that when Mentos came into contact with the beverage, the coat immediately began to break down. Thus the collected results indicate that nucleation is not the main factor, and that it may not be a factor at all. If Professor Coffey and the Mythbusters team was succesful in identifying the key reactants, then the gum arabic of the Mentos may lie in the coat (mind you this is not fact but a prediction). If one wishes to pursue Mentos and carbonated beverage eruptions, but not this particular one, they may want to explore the effect of temperature on eruption intensity, or the effect of carbonation. More ideas still are nozzle position, soda types, or even items besides Mentos. All are interesting fields one may pursue, and can provide important insight to the scientific world.

Endnotes: 1. Mentos Review Article: Effect of Nucleation Sites on Mentos by Caleb F, Guilford J. Chem., 2009-2010, pp. 9-11. 2. Nucleation Sites and the Diet Coke-Mentos Reaction: A Review by Ted J, Guilford J. Chem., 2009-2010, pp. 18-20. 3. How the Coatings of Mentos Affects the Size of the Mentos Eruption by Carly C and Jenn A, Guilford J. Chem., 2007-2008, pp. 17-18. 4. The Height of the Mentos Eruption Depends on the Outside Coating, by Jenna P. Guilford J. Chem., 2011-2012, pp. 31-32. 5. Diet-Coke and Mentos: What is Really Behind this Physical Reaction? By Tonya Shea Coffey Am.J. Phys. 2008, Vol. 76, No.6, pp. 551-557.


Crushed Mentos Create an Eruption that is, on average, 44 cm Less than Full Mentos By Laurel Z. and Ashley I. Summary- The Mentos and diet cola eruption is a well-known experiment.1 When Mentos are dropped into a newly opened bottle of diet cola; a large amount of the cola will suddenly shoot out of the mouth of the bottle. Depending on the size of the cola and the number of Mentos you drop in, the height that the cola will erupt to ranges from a few inches to many feet.1 The effect of placing crushed Mentos in Diet Pepsi versus the effect of placing regular Mentos in Diet Pepsi was tested. Six Mentos were dropped into a 12oz bottle of Diet Pepsi as a control and then five crushed and one full Mentos were dropped into another 12oz bottle of Diet Pepsi as the experiment. A total of three trials were performed. In the end, it was found that the crushed Mentos created an eruption that was, on average, 44 cm less than that of the eruption of the full Mentos. This disagrees largely with Emily’s Ring and Kipness’s experiment because their results showed that slicing Mentos in half results in an eruption that is double the height of regular Mentos.2 This agrees largely with the experiment that Sara D. and Alex B. did because they’re results showed that crushing Mentos will not make the eruption larger.3 Introduction- The Diet Coke and Mentos experiment conducted by Dr. Tonya Shea Coffey concluded many things. The soda with the sample that both lost the most mass and sprayed the farthest was Diet Coke with fruit Mentos.1 They also found that higher the temperature of the soda, the more mass it would loose during the reaction.1 There is still much to be experimented with the Diet Coke and Mentos eruption.

Experimental Section1. Bring in one six-pack of twelve milliliter bottles of Diet Pepsi 2. Bring in three packs of mint Mentos 3. Go outside and find a wall with bricks 4. Measure how many centimeters are in one brick 5. Put one bottle at an angle in front of the wall 6. Get a Geyser tube and insert the pin and put in six Mentos 7. Put on safety goggles 8. Unscrew soda cap 9. Screw on Geyser tube 10. Pull out the pin 11. Look to see the highest point that the eruption reaches 12. Record data


13. Repeat steps five through twelve three times 14. Cut five Mentos with scissors into four pieces 15. Get a Geyser tube and insert the pin and put in one Mentos Results- The results are summarized below in Table 1. For the first trial that was conducted, the full Mentos eruption hit a height of 189 cm while the crushed Mentos only reached a height of 175 cm. In this trial, the full Mentos had an eruption that was 14 cm higher than the crushed Mentos. In the second trial that was conducted, the full Mentos eruption hit a height of 294 cm while the crushed Mentos only reached a height of 203 cm. In this trial, the full Mentos had an eruption that was 91 cm higher than the crushed Mentos. During the third trial that was conducted, the full Mentos eruption hit a height of 315 cm while the crushed Mentos only reached a height of 287 cm. In this trial, the full Mentos had an eruption that was 28 cm higher than the crushed Mentos. On average, the crushed Mentos reached a height that was 44 cm lower than that of the full Mentos. The possible error bars are quite small. There may have been some error depending on the time that we took to open the bottle of soda and to screw the geyser tube on. Conclusion- In the experiment we conducted, we found out that the crushed Mentos decrease the height of the eruption of an average of about forty-four centimeters. The reason for this decreasing eruption is that since the Mentos are cut up, there is less coating, which triggers less of an eruption. This agrees with Carly Clark and Jenn Agamie’s experiment.5 Their experiment proved how the coating of Mentos affects the size of the eruption. This is significant because it demonstrates that if the Mentos are physically altered that the results will not be as high. The experiment that we performed agrees with Marley S. and Teresa L.’s experiment.4 Their experiment showed that physically altered Mentos create a lower eruption than whole Mentos. Endnotes: 1

Diet Coke and Mentos: What is really behind this physical reaction? Tonya Shea Coffee, Am. J. Phys. 2008, volume 76, number 6, pg. 551-557 2 Mentos Sliced in Half will Double the Height of a Mentos Eruption. Emily’s Ring and Kipness, Guilford J. Chem., 2008-2009, pg. 38 3 Crushing Mentos will not make the eruption larger. Sara D. and Alexa B., Guilford J. Chem., 2011-2012, pg. 38-39 4 A Physically Altered Mentos Creates A Lower Eruption Than A Whole Mentos. Marley S. and Teresa L., Guilford J. Chem., 2010-2011, pp. 34-38 5 How the Coatings of Mentos affects the size of the Mentos Eruption. Carly Clark and Jenn Agamie, Guilford J. Chem., 2007-2008, pg. 19-20


The Effect of Different Diet Soda Brands on the Height of Mentos Eruptions By: Mackenzie C. Natalia P. Amanda P.

Summary For the experiment, two different soda brands were used to determine if a different carbonated drink would create an effect on the eruptions height. The two different soda brands used were Diet Pepsi and Diet Coke. In previous research diet coke was usually the best diet drink to use to erupt Mentos. This experiment showed that this is not just a reaction with diet coke because the Diet Pepsi drink worked to erupt the Mentos as well. Diet Pepsi reached the highest height of 525 cm. and Diet Coke’s highest height was 385 cm. The Diet Pepsi reached a higher height than the Diet Coke, which shows that Diet Pepsi works better in Mentos eruptions and contradicts previous research that shows that Diet Coke is better. Introduction When the Mentos eruptions have been done in the past they used the same focus, but were different in the way they were conducted. For our experiment we used just two soda brands. The different soda brands, which were Diet Coke and Diet Pepsi, were the independent variable and the experiment was conduced solely to determine which carbonated drink would prove the best. The results, that are also the dependent variable, showed that Diet Pepsi had the highest eruption heights of 525 cm, 490 cm, and 455 cm whereas; the Diet coke only reached a highest height of 385 cm. Even Diet Pepsi’s lowest height of 245 cm still beat Diet Coke’s lowest height by 70 cm. Previous tests for the Mentos eruptions created different results, but in one particular experiment previously done the results were similar to the results gathered in this experiment.


“The Conclusions from the Mentos experiment are a shown: Diet Pepsi reached the highest height of 73 ft. When Diet coke was used the highest explosion height was only 46 ft. thus showing that Diet Pepsi is the better carbonated drink to use.�i Through this experiment it can be concluded that Diet Pepsi is the better carbonated drink to use than Diet Coke because it got higher results in the eruption.

Experimental Materials: 200 individual Mint Mentos, 16 12floz bottles of Diet Coke, 16 12floz bottles of Diet Pepsi, geyser tube, white board to use as a platform, plastic bag for trash, safety goggles Procedure: 1. Get all supplies 2. Take one 12floz bottle of Diet Coke and 6 Mentos from supplies 3. Put Mentos into geyser tube 4. Place platform on ground and place bottle on top of it 5. Open bottle and place geyser tube on bottle 6. Release pin on geyser tube to drop Mentos and walk away from area to observe and record height 7. Measure height of eruption and record data 8. Repeat steps 2-6 with the rest of the bottles of Diet Coke 9. Repeat steps 2-6 with all of the bottles of Diet Pepsi 10. Analyze data Results


Trial

Diet Coke

Diet Pepsi

1

217 cm

245 cm

2

217 cm

336 cm

3

245 cm

294 cm

4

266 cm

350 cm

5

280 cm

266 cm

6

385 cm

420 cm

7

301 cm

343 cm

8

175 cm

378 cm

9

210 cm

420 cm

10

217 cm

490 cm

11

259 cm

525 cm

12

259 cm

455 cm

13

280 cm

525 cm

Averages: Diet Coke: 254.6923077 cm Diet Pepsi: 388.2307692 cm


Height of Eruptions (cm)

Height of Mentos Eruptions with Different Brands of Diet Soda 400 350 300 250 200 150 100 50 0

Average

Diet Coke

Diet Pepsi Diet Soda Brand

Conclusion The results reject the initial thought of which brand of diet carbonated soda would erupt the highest. The hypothesis was that Diet Coke would erupt to a higher point than Diet Pepsi because people always say the Diet Coke and Mentos eruptions and not Diet Pepsi. This was rejected because the average height of Diet Pepsi was 388.2307692 cm while the average height of the Diet Coke was 254.6923077 cm. The Diet Pepsi’s average height was a meter and a half taller than the Diet Coke. This is due to the fact that there is 10mg less sodium in Diet Pepsi than Diet Coke. Also, Diet Coke uses potassium citrate while Diet Pepsi uses potassium benzoate. Potassium citrate regulates the acidity in the Diet Coke while potassium benzoate is used as a preservative. Potassium benzoate being used as a preservative helps keep the carbonation of the Diet Pepsi stable, which in turn makes the eruptions go higher. A follow-up experiment would include figuring out what brand of Mentos would make the eruptions go highest.


Endnotes i

The Effect of different carbonated beverages on Mentos eruptions. A review by Courtney S, Guilford J. Chem., 2009-2010, pp.28-30.


Whole Mentos Have a 15% Increase of Eruption Height Compared to Mentos that Were Broken into Halves and Quarters By Morgan D. and Sami C.

Summary In this study, Mentos were split in half and in quarters to see if the eruption would go higher in Diet Pepsi than an eruption of whole Mentos in Diet Pepsi. The data that was collected shows that the halves and quarter Mentos actually went on average 15% lower than the whole Mentos. Our data supports the results of several other experiments where they also altered the shape of the Mentos.

Introduction In the Mentos eruption experiment, several Mentos are dropped into a bottle of cola. The Mentos create an eruption that shoots through the mouth of the bottle and up into the air.1 Depending on how many Mentos used and the size of the bottle of cola the eruption heights will be different. The surface of the Mento may have an effect on the eruption height because the outer coat of the Mento is not completely smooth.2 Additionally, Diana and Sarah showed that changing the outer coat with dish soap does not increase the height of the eruption either.3 When the Mentos were physically altered, such as crushing them, it was found that it took long and the


eruption was lower.4 Sara and Alexa’s experiment supports that crushing the Mentos does not help and causes the eruption to be 81 inches lower than regular Mentos.5 There is one experiment where the Mentos were cut in halves, quarters, and also crushed, and the data shows that the whole Mentos caused the highest eruption.6 Overall, these experiments show that changing the surface or the shape of the Mento lowers the eruption height of the cola. In order to see if surface area really does affect the eruption height of the cola, we decided to design an experiment where the Mentos are split in half and in quarters to see if the eruption are any bigger than regular Mentos.

Experimental Materials: 1. 2. 3. 4. 5. 6. 7.

Nine 12 ounce bottles of Diet Pepsi 54 Mentos Geyser tube Pencil Timer Safety goggles Flat board/surface

Procedure: 1. Put on safety goggles and wear throughout the experiment 2. Put 6 whole Mentos into geyser tube 3. Place unopened soda on flat board/surface and angle it toward a wall


4. When soda is opened start timer and place geyser tube on soda 5. When timer reaches 20 seconds, release Mentos into soda 6. Record the height of the eruption according to the mark on the wall from the soda 7. Repeat steps 2-6 two more times 8. Split 6 Mentos in half by pushing a pencil in the center 9. Put the 12 halves into the geyser tube 10. Repeat steps 3-6 11. Split 6 more Mentos in half with the pencil and place in geyser tube for second trial 12. Repeat steps 3-6 13. Split 6 more Mentos in half with the pencil and place in geyser tube for last trial 14. Split 6 Mentos into quarters with pencil and place in geyser tube 15. Repeat steps 3-6 16. Split 6 Mentos into quarters with pencil and place in geyser tube for second trial 17. Repeat 3-6 18. Split 6 Mentos into quarters with pencil and place in geyser tube for last trial

Results In this experiment, when six Mentos were dropped into twelve ounce bottles of Diet Pepsi, the whole Mentos went an average height of 140 cm, while the halves and quarters of Mentos both went an average of 119 cm. This data shows that when Mentos are cut in half or quarters that the eruption will go 21 cm or 15% lower than an average whole Mento eruption. Whole Mentos ½ Mentos Ÿ Mentos

Trial 1 154 cm 126 cm 133 cm

Trial 2 112 cm 112 cm 105 cm

Trial 3 161 cm 112 cm 112 cm

Average 140 cm 119 cm 119 cm


Conclusion Our results show that the height of the eruption was larger with whole Mentos than broken Mentos. We think this because there was less of the rough covering of the Mentos. This is where the carbon dioxide bubbles stay causing the eruption. Since there is less space for it, there is a smaller eruption taking place. This suggests that the interior of the Mento is actually smoother than the outer coating that is placed on the Mento. The evidence supports the results of four other experiments in that the whole Mentos went higher. However, it did not have a difference as high as the other experiments, such as the one by Diana and Sarah. Our tests were not completely identical because we tested halves and quarters and the other experiments tested crushed Mentos. We did numerous trials so there were few errors in our data. Another follow-up experiment could be testing other materials with a similar surface as to that of a Mentos to see if the surface is what affects the eruption.

Endnotes 1

Diet Coke and Mentos: What is really behind this physical reaction? Tonya Shea Coffey, American Journal of Physics, Volume 76, Number 6, pp. 551. 2 ibid, p.556. 3 Solid Mentos Create Eruptions 5 Times Higher Compared to Crushed Mentos. Diana C. and Sarah G., Guilford Journal of Chemistry, Volume 4, 2010-2011, pp. 15-19. 4 A Physically Altered Mentos Creates A Lower Eruption Than A Whole Mentos. Marley S. and Teresa L., Guilford Journal of Chemistry, Volume 4, 2010-2011, pp.34-38. 5 Crushing Mentos Will Not Make the Eruption Larger. Sara D. and Alexa B., Guilford Journal of Chemistry, Volume 5, 2011-2012, pp.36-37. 6 Increasing Surface Area of Mentos Generally Causes Eruption Height to Decrease. Alicia R., Sarah R., and Casey S., Guilford Journal of Chemistry, Volume 4, 2012-2011, pp. 20-21.


The Larger Tube Angle, 360˚, produces a 65% Decrease in the Height of the Mint Mentos Eruption in Comparison to a 0˚ Tube Angle By Sydney S. and Krissa C. I.

Summary

The objective of this experiment was to discover how different angle measures affect the height of a Mint Mentos eruption. This was performed by testing three different tube structures (1.0 m), with varying angle measurements that were attached to the mouth of the geyser tube. The geyser tube was then screwed on to a 16 oz. diet coke bottle and contained six Mentos that would be later dropped to cause an explosion. The three tubes measured at angles of 5˚, 45˚, and 360˚, with their structures being straight, S-shaped, and looped respectively. A tube was not involved when testing the control, having no angle measurement or in this case, 0˚. The height of the Mentos eruption was recorded depending on the number of bricks that the diet coke covered. Each brick was measured at 7.5 cm or .075 m. Three trials were completed and averaged to determine which tube had the greatest influence on the height of the Mentos eruption. As the angle increases, the height of the Mentos eruption decreases due to extra pressure needed to push the diet coke through the tube. The control reached an average height of 2.8 meters (37 bricks), the straight tube had an average height of 1.9 meters (25 bricks), the looped tube was .98 meters (13 bricks), and the S-shaped tube obtained a height of 1.7 meters (22 bricks). As a result, the control proved to produce a 65% increase in the height of the Mentos eruption in comparison to the 360˚ tube, in this case the largest tube angle. II.

Introduction

Mentos eruptions are often being investigated by scientists to focus on the cause of this physical change or to complete as an activity at home or at school. This particular eruption is due to the ingredients in both the diet coke and the Mentos. For instance, the diet coke is comprised mostly of carbonated water and sugars, such as aspartame. On the other hand, the Mentos contain no carbonates, mostly sugars, gelatin, and gum arabic. This composition is responsible for nucleation, which is when CO2 bubbles form on the Mentos surface once the mints enter the diet coke. The Mentos are denser, so they sink to the bottom of the diet coke bottle. At the bottom, enough pressure builds due to the separation between water molecules causing an explosion. Lee Marek was first acknowledges for performing the typical Mentos eruption on the David Letterman Show by releasing Mentos in a diet coke bottle. Over time, the idea attracted many scientists to enhance the concept behind the experiment. Specifically, the Myth busters experimented with the original Mentos, but also compared the height of the


eruption by incorporating fruit flavored Mentos. The Myth busters found that the flavored Mentos did provide a substantial height difference in comparison to the mint Mentos. However, these results are due to the fact that the Myth busters added an extra coating to the flavored Mentos causing the eruption have a smaller reaction. The results of the eruption were influenced by factors, such as the type of ingredients within the diet coke and flavored Mentos and the texture of the Mentos. A third experiment was tested by the students at Appalachian State University, who experimented with different substances, other than Mentos, that were dropped within the diet coke bottle. The students expanded upon the factors that may influence the height of the eruption, such as temperature and caffeine. Once these particular experiments were completed, they all demonstrated that a larger amount of fake sugar results in a larger explosion. III.

Experimental/ Procedure A procedure was followed to complete the experiment: 1. Buy twelve 16-ounce diet coke bottles and seven roles of Mint Mentos 2. Find a location near a brick wall in order to use the bricks as a measurement to determine the height of the Mentos eruption 3. Place a board with a hard surface next to the brick wall 4. Angle the board towards the brick wall by placing a rock underneath the board 5. Place six Mint Mentos in the plastic geyser with the pin through the bottom to prevent the Mint Mentos from falling out the other end of the geyser 6. Place the end of the straight tube over the mouth of the plastic geyser 7. Tape the plastic geyser and the straight tube together 8. Put on safety goggles 9. Place a diet coke bottle on the board in front of the brick wall and remove the cape 10. Immediately place the open end of the plastic geyser and screw it on the mouth of the diet coke without pulling the pin and releasing the Mint Mentos 11. Once the plastic geyser is secured on the diet coke bottle, pull the pin to release the Mint Mentos and trigger the eruption 12. Count the number of bricks that are soaked to measure the height of the eruption 13. Record the results and repeat with the straight tube until three trials are complete 14. Repeat steps 5-13 with the control, the looped tube, and the S- shaped tube


After examining the results, it was found that the larger tube angle, 360Ëš, was not effective in producing an increased height in the Mentos eruption. The results consisted of the control having the maximum average height of 2.8 m (37 bricks), whereas the minimum average height was .98 m (13 bricks) for the looped structure. The difference in percent between the two heights was 65%. These results could be due to the variation in angle measurements, which


affects the rate at which the diet coke flows through the tubes. Errors that could also have an impact on the results are the delay between screwing the geyser on to the mouth of the diet coke bottle and releasing the Mentos to begin the eruption. By delaying the time to release the Mentos, the carbonation immediately begins to decrease reducing the amount of pressure, which causes the eruption to have difficulty reaching its potential height. Also, the angle at which the tube was directed against the brick wall varied between each trial, and each tube tapped to the geyser over time detached as the number of trials progressed. With the tube being aligned at a different angle against the brick wall it causes different directions of the diet coke as it explodes through the mouth of the tube. Also, when the tube becomes detached to the geysers, only being held by the tap, pressure is being released, as well as diet coke, decreasing the height of the eruption. For further experimentation, in order to obtain accurate results, it is necessary to place the same object in a set location underneath the surface the diet coke bottle is placed to allow the diet coke to be directed at a constant angle against the brick wall. A solution to prevent the tube from detaching the geyser would be to cut a centimeter long slit on the edge of the tube to allow the tube to slide over the mouth of the geyser. By solving several errors that occurred in the prior experiment, future experiments will be able to record accurate results explaining the average height of a Mentos eruption.


The Effect of Putting 5,7,9, and 11 Mentos to Change the Height the Soda Erupts to 92 Bricks Summary By: T.J. W, Luke N. For our experiment we took four different amounts of Mentos in the sleeve to see the effect that it would have the diet coke. The amount of Mentos that were used was 5, 7, 9, and 11. By doing this, we were able to see if the amount of Mentos that are used would affect the eruption of the soda in any way. With previous knowledge in this topic we were able to know what would happen when we performed it. When we did the experiment we found out that 11 Mentos made the eruption go up 92 bricks, 7 Mentos had the next largest eruption with 89 bricks, then 5 Mentos came in third with 86 bricks, and 9 Mentos was the smallest eruption with 83 bricks. The reason that the 9 Mentos eruption was the smallest amount was because there was an error with that trial that led to uneven data. Also in our experiment we used all mint Mentos and that was proven to be the most consistent compared to the fruit Mentos and in their experiment all of their trial were around 100 bricks while the fruit Mentos had scattered results.i We did not have another soda bottle to run the test again so we kept the data that we had.

Introduction There have been many people before us to perform this test on many different levels than we did. Other people had some of the same results, as we did like 86 bricks for 9 Mentos.ii We realized that their results confirmed that our experiment was correct. We did have uneven data because there were faults when we performed one of the trials. We saw in other experiments that one of their trials were extremely different than other trials but the data was still reliable. One of their trials was at 9.5 and another trial was at 2.iii To make sure that all of our tests were not wrong we found other people’s data that was similar to ours. Their experiment was around 60 bricks when they waited 30 seconds when there was less carbonation but if they did it earlier then it would have been around our data.iv With help from other student research we will be able to find the precise data that will prove all of our research.

Experimental Materials: 4 2liter bottles of diet coke, multiple packages of mint Mentos, geyser tube where you put the Mentos in, nozzle where the soda comes out, brick wall behind it 1. 2. 3. 4. 5. 6. 7. 8. 9.

Get materials Place 5 Mentos in geyser tube(loading tube on top of soda) Place bottle of diet coke next to wall at an angle to get accurate measurements Open the cap on the coke bottle Insert tube into top of bottle Screw the cap of the nozzle onto the bottle Pull the pin to release the Mentos into the coke to create eruption Count how high the eruption went by bricks Repeat steps with 7,9, and 11 Mentos


10. Record data Results

Mentos Eruptions 94 92

Height in Bricks

90 88 86

Series 1

84 82 80 78 5 mentos

7 mentos

9 mentos

11 mentos

Amount of Mentos

These numbers show us that when 11 Mentos are added to the coke then it will create the biggest eruption. That reached up to 92 bricks. 9 Mentos had the smallest eruption of 83 bricks but we are confident with all of the other test we saw and the other research that that should be the next largest eruption. 7 Mentos had the third largest eruption with 89 bricks. 5 Mentos had the third smallest eruption with 86 bricks. If we were able to perform more trials then our results would be more accurate.

Conclusion In our experiment, we found that if you use 11 Mentos then the eruption will go higher. This should also be the case for any amount of Mentos that is higher than another amount. The reason why that 11 Mentos would go the highest is because there is more CO2 being produced. When Mentos are dropped into the soda they release CO2 and the more Mentos being dropped the more CO2 that will be released and the higher the eruption will go. v The soda with the most Mentos went 3 bricks higher than any other eruption. We were not able to perform multiple tests to ensure that our data was accurate. In other experiment that we saw, they had multiple trials that were able to exclude a result that was obscure. vi The results now could have been much better than they are and it is in fault of the lack of supplies. There was more power being put into the soda when more Mentos were being added and that is why the eruptions were higher. If we were to do this experiment again then we would make sure that we had more materials with us to do more trials. This will make sure that what we are doing wrong can be fixed a


second time we do it. We would make sure that everything is put on correctly to make sure that it is working right for accurate data. We would take our time in doing it to make sure that there are no faults in what we are doing.

Endnotes: i

Ibid, page 7 Craig A. The Guilford Journal of Chemistry, Volume 5, pages 6-7 (2011-2012). iii Clair W and Lindsey U. The Guilford Journal of Chemistry, Volume 5, pages 21-25 (20112012). iv Olivia S and Bronwyn R. The Guilford Journal of Chemistry, Volume 5, pages 51-54 (20112012). v Gabriella Necklas and Kiersten Wall. The Guilford Journal of Chemistry, Volume 1, pages 2325 (2007-2008). vi Allison Federici and Jess LaChance. The Guilford Journal of Chemistry, Volume 2, pages 1516 (2008-2009). ii


Mint- Fruit Combinations Can Erupt 8% Higher than Mint or Fruit Alone in a Mentos Eruption By Grace C. and Madisen P. Summary: This experiment tested the effect of various combinations of mint and fruit Mentos on eruption height. We hypothesized that if the amount of fruit in the ratio of mint to fruit Mentos increases, the eruption height will correlate directly. Seven 12 ounce Diet Pepsi bottles and both mint and fruit flavored Mentos were used to conduct this experiment. Only one trial was executed for each combination of Mentos. To calculate how high each Mentos eruption went, we counted the number of bricks that were sprayed by the soda. Then we measured the height of a single brick and concluded that it is 2.25 inches high. With this information, we were then able to figure out how high the eruptions were in inches. Our most successful eruption consisted of 2 mint and 4 fruit Mentos was 108% higher than our lowest eruption containing 1 mint and 5 fruit Mentos. Introduction: The Mentos eruption involves dropping Mentos into soda, most commonly used with Diet Coke or Pepsi. The more Mentos dropped into the soda results in a higher eruption height according to the report called “How the Amount of Mentos Affects the Height of the Eruption” 4. This experiment was originally brought to society’s attention when shown on the David Letterman show in 1999 5. Additionally, it was the main focus of a Mythbusters episode in 2006 6. It was decided to use Diet Pepsi, rather than another beverage such as Diet Coke, because it is known for producing the highest eruption heights in Mentos experiments. This information was found in a report called, “Diet Pepsi- Not Diet Coke- Results in the Highest Mentos Eruption When Compared to Other Diet Carbonated Drinks”7. Next, the hypothesis stated that the fruit Mentos would cause a more enhanced eruption than mint Mentos. This theory was based on prior knowledge from reading the Tonya Coffey paper settles that fruit Mentos create a higher eruption height than mint flavored ones 8. Experimental Section: 1. Gather supplies: 3 packages of Mint Mentos, 3 packages of Fruit Mentos, and 1 8pack of 12 fluid oz. of Diet Pepsi


2. Unscrew the cap of one Diet Pepsi. 3. Immediately following, screw on the nozzle 4. Insert 6 Mint Mentos. Pull string and erupt. 5. Count bricks that were hit by eruption and record results. 6. Repeat steps 2 & 3 7. Insert 5 Mint Mentos and 1 Fruit Mento. Pull string and erupt. 8. Count bricks that were hit by eruption and record results. 9. Repeat steps 2 & 3 10. Insert 4 Mint Mentos and 2 Fruit Mentos. Pull string and erupt. 11. Count bricks that were hit by eruption and record results. 12. Repeat steps 2 & 3 13. Insert 3 Mint Mentos and 3 Fruit Mentos. Pull string and erupt. 14. Count bricks that were hit by eruption and record results. 15. Repeat steps 2 & 3 16. Insert 2 Mint Mentos and 4 Fruit Mentos. Pull string and erupt. 17. Count bricks that were hit by eruption and record results. 18. Repeat steps 2 & 3 19. Insert 1 Mint Mento and 5 Fruit Mentos. Pull string and erupt. 20. Count bricks that were hit by eruption and record results. 21. Repeat steps 2 & 3 22. Insert 6 Fruit Mentos. Pull string and erupt. 23. Count bricks that were hit by eruption and record results. 24. Clean up materials and recycle bottles! Results:


The results, shown in the table demonstrate what occurred during each trial. In the first trial, there were 6 mint Mentos which resulted in a 38.25 inch high eruption. The second trial with 5 mint and 1 fruit Mento had an outcome of the exact same height eruption with 38.25 inches. The following experiment contained 4 mint and 2 fruit Mentos caused a 33.75 inch eruption. Next, we used 3 of each type of Mento which produced an eruption of 51.75 inches. After, 2 mint and 4 fruit Mentos created a 56.25 inch eruption height. Then, 27.0 inch eruption height was made from 1 mint and 4 fruit Mentos. Finally, 6 fruit Mentos generated a 51.75 inch eruption height. On the bar graph above, it depicts multiple different eruption heights in an unorganized manner. What should have occurred is either a constant negative or positive sloped graph. Conclusion: After the experiment was conducted, we realized our results are unreliable due to many different factors. There is a large margin for error of about 25% throughout this procedure. Multiple parts of the experiment did not turn out as planned. For example, sometimes the bottles were accidentally placed at too much of an angle to the wall, resulting in a lower eruption height due to the soda being pointed too directly toward the wall. Next, many trials had to be redone because the bottle would tip over after the string was pulled. Therefore causing the bottle to fall and spray soda in the opposite direction. The last thing that could have been improved is that more trials should have been completed to receive more accurate and dependable results. All of these improvements will be taken into consideration in the future. The results should have turned out differently. After performing the experiment, we were able to conclude from our data that combinations with greater amounts of fruit than mint produce a higher eruption height. Although if the experiment were to be repeated, the results could easily turn out differently. This is due to the numerous errors that took place throughout the trials. In conclusion, Mentos eruptions with more fruit than mint Mentos in combinations produce a higher eruption height.


Endnotes 1. “How the Amount of Mentos Affects the Height of the Eruption.” By Matt Feldman and Alex Monte, Guilford J. Chem., 2008-2009, p. 27. 2. Coffey, Tonya. “Diet Coke and Mentos: What is really behind this physical reaction?” June 7, 2007: p. 551. 3. Coffey, Tonya. “Diet Coke and Mentos: What is really behind this physical reaction?” June 7, 2007: p. 551. 4. “Diet Pepsi- Not Diet Coke- Results in the Highest Mentos Eruption When Compared to Other Diet Carbonated Drinks.” By Angelise Musterer and Lindsay Ruotolo, Guilford J. Chem., 2008-2009, p. 12-14. 5. Coffey, Tonya. “Diet Coke and Mentos: What is really behind this physical reaction?” June 7, 2007: p. 552.


Various Holes and Designs Placed On Tape Can Significantly Affect Mentos Eruption By Kathryn B. and Katie E.

Summary: We tested the effects that different nozzle designs would have on the spray of a Mentos eruption. The designs were cut into pieces of tape, and then secured on the nozzle of the eruption maker. One regular, 16 oz. Pepsi and three Mint Mentos were used for each trial. The designs were a line-shaped puncture, an upside-down Y-shaped puncture, a design consisting of 16 dots deposited onto the tape, and a downward eruption where the tape was only loosely adhered onto the nozzle of the eruption shooter, causing the Pepsi to flow out the uncovered spaces. The average height of each eruption was as follows: the line-shaped eruption had 11 bricks, the 16-dots eruption had 12 bricks, the upside-down Y-shaped eruption got 7 bricks, and the downward eruption had 2.5 bricks.

Introduction: The classic Mentos eruption was dropping Mint Mentos into a container of Diet Coke, and watching the physical reaction occur as the Coke rushes out of the top of the container as a thrilling jet of light-brown liquid. This is a physical reaction due to the fact that the Mint Mentos create a place where carbon dioxide can expand and eventually shoot out of the bottle. Many different experiments have been tested involving other sodas and candies. Our experiments affected the height and pattern of the eruptions.

Experimental Section: 1. Obtain the following items: one 6-pack of regular, 16 oz. Pepsi soda, 2-3 packs of Mint Mentos, tape, a paper clip, and a red plastic eruption shooter. 2. Find a flat surface, preferably outside, and mark different heights on brick or a wall. 3. Set the diet Pepsi close enough to the wall so that height can be clearly recorded. 4. Place three Mint Mentos into the eruption shooter, and fasten the shooter’s string in place to keep the candy from falling out. 5. Using the paper clip, trace the desired design onto a piece of tape and place the tape on top of the eruption shooter. Be sure that no spaces are left uncovered. 6. Open one bottle of soda and quickly secure the eruption shooter onto the nozzle of the soda. 7. Pull the string quickly as one person holds the bottle to keep it from tipping, and record the height of the eruption on paper. 8. Repeat steps 3-7 again, then with different designs, so that each design has been tested at least twice. Record all data.


Conclusion: Our results show that the more mentos added to the soda does steadily increase the height of the soda. The numbers went up at around the same, but as the more mentos were added, the numbers went up at a slower rate. The average height of 1 mento was 18 inches and the average for 2 mentos was for 32.625 inches. That is an increase of 14.625 inches. The average for 3 mentos was 46.125 inches. From 2 mentos to 3 mentos was a difference of 13.5, 1.125 less than 1 to 2. The average height for 4 mentos was 56.25. From 3 to 4 had a difference of 10.125, 3.375 less than 2 to 3. This may mean that adding more mentos will increase the height but the more and more mentos you add, the less the difference is going to be. Eventually, the numbers will increase infinitely small not making much difference. We can try this experiment using more mentos for more results to help prove this or try different sodas/mentos and still will most likely get the same results. Another experiment we can try is seeing if we get the same effect with different types of sodas/ mentos and see if they are identical or very similar. Some flaws that we may have had could be that we had conducted only 2 trials for each amount of mentos (mainly due to supply issues). 3 or 4 trials would have been much more accurate. Also, some of the sodas may have been open longer causing less accurate data. If we had timed exactly how long it was after we opened the soda we might again get better results. Endnotes: 1. How the Amount of Mentos Affects the Height of the Eruption. Matt Feldman and Alex Monte, Guilford J. Chem., 2008-2009, pp. 29-31. 2. Increased Temperature of Diet Coke and Number of Mentos Increases the Height of Mentos Eruption. Anna K., Guilford J. Chem., 20011-2012, pp. 15-16. 3. Diet Coke and Mentos: What is really behind this physical reaction? Tonya Shea Coffey. Department of Physics and Astronomy, Appalachian State University. Received 7 June 2007; accepted 5 February 2008. 4. Mint Mentos Erupt 16% Higher than Strawberry Mentos and 55% Higher than Green Apple Mentos with Diet Coke. Anny Y., Guilford J. Chem., 2011-2012, pp. 11-14. 5. The Effect of Different Sodas on the Height of a Soda and Mentos Eruption. Jacob H., Ben B., Colton S., Guilford J. Chem., 2011-2012, pp. 4-5.





Table of Contents: Three-dot Nozzle Causes an Eruption Averaging 32.7% Higher than Commonly-Used One-Dot Nozzle By: Allison B, Sammy C, and Ashley H………………………………….…. …4 An Increased Drop Height Causes Only 0.3 grams Less Soda to Leave the Bottle During a Diet Coke and Mentos Eruption; Evidence of Very little Change By: Rachel G. and Emily S………………………………………………………………………..8 Mentos Mashed Into a “Pancake” Erupt, on Average, 48% Lower than Regular Mentos By: Henry R. and John R……………………………………………………………………………….....12 Loud Low Pitch Sounds Produce a 21% Increase in Eruption Height When Mixing Minty Mentos With Regular Coca Cola By: Jack D. and Kyle E....……………………...…………….17 Sprite Zero Erupts 7% Higher than Diet Coke in Comparison to Four Sodas By: Lucila K. and Lindsay L……………………………………………………………………………………………..20 The Diet Coke and Mentos Eruption Using the Standard Geyser Tube Erupted 52.3% Higher than the Modified Nozzle By: Jackson I., Sonny C., Tim K………..……………………23


Minimizing the CO2 Lost During the Application of the Geyser Tube Increases the Pressure within the Bottle but Decreases the Height by 8.54% By: Kate V. and Sophie K…….27 Mentos Heated to 30º Celsius Cause an Eruption of Diet Pepsi 32.8% Higher Than Mentos at 25º Celsius. By: Cole H., Sean H., and Logan F………………………………………………...31 Amount of Carbonation Matters - Height of Eruption Decreases 80% When Diet Coke Bottles Opened 48 Hours Prior to Eruption By: Jaimie C and Becca W………………………..38 Coated Fruit Mentos Produce an Eruption Height 35.9% Greater than Those with Removed Coating Report by: Joe I. Tested by: Isaac A. Chris C. and Joe I……………………..42 Crushed Mentos Create an Eruption that is, on average, 44 cm Less than Full Mentos By: Laurel Z. and Ashley I. ..……………………………………………………………………48 The Effect of Different Diet Soda Brands on the Height of Mentos Eruptions By: Mackenzie C. Natalia P. Amanda P……………………………………………………………...50 Whole Mentos Have a 15% Increase of Eruption Height Compared to Mentos that Were Broken into Halves and Quarters By: Morgan D. and Sami C………………………………….55 The Larger Tube Angle, 360˚, produces a 65% Decrease in the Height of the Mint Mentos Eruption in Comparison to a 0˚ Tube Angle By Sydney S. and Krissa C…………...….59


The Effect of Putting 5,7,9, and 11 Mentos to Change the Height the Soda Erupts to 92 Bricks By: T.J. W, Luke N…………………………………………………………………..…..63 Mint- Fruit Combinations Can Erupt 8% Higher than Mint or Fruit Alone in a Mentos Eruption By Grace C. and Madisen P……………………………………………………………66 Various Holes and Designs Placed On Tape Can Significantly Affect Mentos Eruption By Kathryn B. and Katie E………………………………………………………………………70


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