Environmental Science - 3rd simulation - Gases

Gas Properties Worksheet

 Learning Goals: Students to be able to

A. Describe what happens to the measurable  quantities if changes to a gas system are made.

B. Relate the amount of energy of the gases to resulting molecular motion.

C. Explain using physics what is happening on a molecular level when changes are made to a gas system.

D. Use ideas about pressure and temperature to explain some common phenomena.

Directions:

1.      Open the Gas Properties link http://phet.colorado.edu/en/simulation/ gas-properties  - click on Run Now

2.      Familiarize yourself with the different setting. After clicking on some of the possible options, answer these pre-activity questions using prior knowledge:

3.      People who climb the tallest mountains in the world often use oxygen tanks to help them breathe. If a mountain climber asked you to explain the science behind the “thin air”, what would you say to him?

4.      If you are in a building fire, you are supposed to lie on the ground. Why?

5.      If you are hiking in the mountains and find yourself short of breath, do you think if you lie on the ground you could breathe easier? Why?

6.   Be sure that the Gas Properties program is set to NONE as the constant parameter. Make sure HEAVY gas is clicked. Pump the Handle 4 times and put some gas in the chamber. What happens to the molecules?

7.   Slide the gravity to LOTS. What happens to the molecules at first?

8.   What happens to them after a couple of minutes?

9.   Click RESET. Now click on NONE again and pump more molecules into the chamber.

10.  Click on PRESSURE. A handle has appeared on the left – click on the handle and move the box to the right so it is smaller. What happens to the molecules?

11.  Increase the pressure to 3.5 ATM  - what happens to the box when you let go of the mouse?

12.  What pressure does it move to on its own? Why does that happen?

13.  Click on NONE and add heat at the bottom of the chamber. What happens to the molecules?

14.  As you keep adding heat, watch the pressure gauge. What is happening?

15.  What eventually happens to the chamber and the molecules? Why?

16.  Be sure that the Gas Properties program is set to NONE as the constant parameter. Make sure LIGHT gas is clicked. Pump the Handle 4 times and put some gas in the chamber. What happens to the molecules?

17.  How do they react different than the HEAVY gases?

18.  Carbon dioxide is a heavy gas. Explain how does this simulation help you understand how carbon dioxide interacts in our atmosphere?

19.  How  is this simulation similar to what happens in our atmosphere when discussing the heating of our atmosphere and global warming?

20.  Name 3 things that add heat to our atmosphere and write and essay that describes the effect that they have on our atmosphere in detail.