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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. Coffeeâ&#x20AC;&#x2122;s and Cutler and Smithâ&#x20AC;&#x2122;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. Brielmannâ&#x20AC;&#x2122;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, â&#x20AC;&#x153;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.â&#x20AC;? (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: â&#x20AC;˘ Always wear safety goggles when performing this experiment â&#x20AC;˘ Stand clear of the exploding coke â&#x20AC;˘ 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 eruptionâ&#x20AC;&#x2122;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 bottleâ&#x20AC;&#x2122;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 itâ&#x20AC;&#x2122;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 doesnâ&#x20AC;&#x2122;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 â&#x20AC;&#x201C; 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 didnâ&#x20AC;&#x2122;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. Coffeyâ&#x20AC;&#x2122;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 â&#x20AC;&#x153;Misting Mentos Eruption,â&#x20AC;? 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/Brownâ&#x20AC;&#x2122;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.

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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

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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 didnâ&#x20AC;&#x2122;t have/use Gyzer tube and they didnâ&#x20AC;&#x2122;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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guilford journal of chemistry volume 4 (2010-2011)