2Âş ESO
External Dynamics on Earth Natural Science
LAB PRACTISE – WEATHERING BEFORE PERFORMING THE EXPERIMENTS Laboratories are places in which you can discover that topics you have studied in class are real. It is fun to compare theory with real practise. However, laboratories could be dangerous places as well. That is why you should read the instructions on this paper before you start working here. 1. 2. 3. 4. 5. 6. 7. 8.
Security inside the lab Follow all the instructions given by your teacher. Exercise caution and good judgement. Notify the teacher immediately regarding any accident or unsafe areas. Always follow lab procedures exactly. Never do unauthorized experiments. If a chemical spills on your skin, notify the teacher and rinse with water. Handle all equipment carefully. You should never eat or drink in the lab.
Laboratory equipment Attached to this paper you have a sheet with all the equipment you might use in the laboratory. Theory background Answer the following questions. - What happens to rocks after long time exposure to the environment?
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What elements can influence rocks?
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What is weathering?
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How many types of weathering can you think about?
THE EXPERIMENTS Your group will have to perform one experiment for each station set in the lab. Remember that all the members of the group have to take data since the reports will be handed in individually. Use the lab sheets provided. Do not move to the next station until the teacher tells you to do so. If you have any question about the experiment ask your teacher. REMEMBER TO RESPECT THE SAFETY RULES!!
2ยบ ESO
External Dynamics on Earth Natural Science
Station 1. All the groups will do this experiment at the same time. Fill half of a plastic glass with tap water. Mark on a plastic glass the water level. Place the glass inside the freezer. Check it 5 minutes before the end of the class. Mark the new level, measure the difference between both marks. Station 2. Place a piece of gypsum in a beaker with carbonate water and another piece in a different beaker with tap water. Take observations after 20 minutes and after 24 hours. Station 3. Place one coin inside a Petri dish. Pour some vinegar in the Petri dish until the coin is completely covered. Record your observation initially and after 5 minutes. Station 4. Place one whole antacid tablet inside a beaker and fill the rest of the flask with tap water. Note down the time it takes to dissolve. Place a second antacid tablet, this time crushed with a mortar, and fill the flask with tap water. Note down the time it takes to dissolve. Station 5. IN THIS STATION YOU WILL USE A DANGEROUS SOLUTION. BE CAREFUL! Place one piece of limestone rock in a Petri dish. Take some tap water with a dropper and drop some water on the stone. Observe the reaction. Now take the dropper and fill it with hydrochloric acid solution. Drop some of the solution on the rock. Observe the reaction. Station 6. Place a sugar cube inside an Erlenmeyer flask with a thermometer. Fill the flask with cold tap water. Note down the time it takes to dissolve and the temperature. Place a second sugar cube inside an Erlenmeyer flask with a thermometer. Heat some water with a burner and pour it inside the flask. Note down the time it takes to dissolve and the temperature. REPORTS After performing the experiments you will need to prepare a report and hand it in. In this report you should include the following points: - Theory background: questions answered at the beginning of the experiments. - Materials used. List them, some drawings can be done. - Methods. Explain how you have performed each experiment. - Results. Include the data you have obtained for each station. - Conclusion. Looking at your results try to guess what is the relationship between these experiments and what happens in real life.
2ยบ ESO
External Dynamics on Earth Natural Science
Lab sheet 1- Effects of freezing on water Name_________________________________ Amount of water used____________________ Size of beaker __________________________ Observations Water level before freezing
Water level after freezing
Conclusions____________________________________________________________ ______________________________________________________________________
Lab sheet 2- Effects of water on gypsum Name_________________________________ Amount of water used____________________ Observations Water type Carbonate water
After 20 minutes
After 24 hours
Tap water
Conclusions____________________________________________________________ ______________________________________________________________________
2ยบ ESO
External Dynamics on Earth Natural Science
Lab sheet 3- Effects of vinegar on copper coins Name_________________________________ Observations Immediate reaction
After 5 minutes
Conclusions____________________________________________________________ ______________________________________________________________________
Lab sheet 4- Effects of water on antacid tablets Name_________________________________ Amount of water used____________________ Type of antacid tablets __________________________ Observations Tablet composition Whole Crushed
Time to dissolve
Conclusions____________________________________________________________ ______________________________________________________________________
2ยบ ESO
External Dynamics on Earth Natural Science
Lab sheet 5- Effects of water/hydrochloric acid on limestone Name_________________________________ Amount of water/hydrochloric acid used____________________ Type of limestone __________________________ Observations Solution Water
Reaction
Hydrochloric acid
Conclusions____________________________________________________________ ______________________________________________________________________
Lab sheet 6- Effects of water temperature on sugar cubes Name_________________________________ Amount of water used____________________ Observations Water Cold Warm
Temperature
Time to dissolve
Conclusions____________________________________________________________ ______________________________________________________________________