Air, It's Really There

Transcription

1 Air, It's Really There Learning Target Pre Assess Big Ideas Post Assess I can describe, on the molecular level, the effect of heating and cooling on the motion of molecules of a gas. 1

2 Is it Matter? On a sheet of paper, write the letters of the items that are NOT matter. a. helium b. oxygen e. electricity f. air i. water vapor j. clouds c. radiation g. light k. carbon dioxide d. rock h. heat l. metal 2

3 Demo Does a Gas Have Mass? Ball Before After Compressed Air Before After 3

4 Particles of a Gas Particles of a gas have very little attraction for each other. They collide with each other and bounce off. The space between molecules is made up of nothing. 4

5 EXPLORE Part A: Warming the air inside a bottle. Part B: Cooling the air inside a bottle. 5

6 Explain What happened to the film of detergent solution when you placed the bottle in hot water? What happened to the bubble when you placed the bottle in cold water? 6

7 Animation Red arrows represent the outside air pushing down on the bubble film. Heating the air makes the molecules move faster. Collisions with the bottle and bubble film increase and become harder. This pushes the bubble up. 7

8 Cooling a Gas Cooling the gas makes the molecules move more slowly. These slower moving molecules hit the bottle and bubble film less often and with less force. The molecules in the outside air are moving faster and push the bubble film inside the bottle. 8

9 Compare molecules in a solid, liquid, and gas (same temperature). solid particles are very attracted to one another, vibrate but can't move past one another, has definite volume and definite shape. liquid particles are attracted to one another, vibrate and can move past one another, have definite volume but not definite shape. gas particles are not attracted to one another much at all, move freely, can move past one another, particles spread out evenly to fill a container. 9

10 Take it Further Imagine that you work at a party store during the summer. You are going to ride home with the owner of the store whose car has been sitting in the hot sun all day long. The owner tells you that you can take home a bunch of balloons, but advises you to not blow the balloons up all of the way. Knowing what you do about the heating the molecules of a gas, explain why the owner's advise is wise. 10

11 Is it Matter? On a sheet of paper, write the letters of the items that are NOT matter. a. helium b. oxygen e. electricity f. air i. water vapor j. clouds c. radiation g. light k. carbon dioxide d. rock h. heat c, e, g, h l. metal 11

12 Molecules in Moon Writer s Frame Write about molecules arrangement, moon, and speed. In Acvity 1.1, 1.2, and 1.3, we learned about molecules in a liquid. In these acvies, I found out molecules in a liquid are When molecules in a liquid are heated, they. In acvity 1.3, I learned that when thermometers are placed in a hot liquid, the red liquid moves up the tube because. In acvity 1.4, I learned about the molecules in a solid. When the solid was heated, the molecules. In the final acvity, I learned about the molecules in gases. First of all, I learned that gases are maer because Then I heated air in a bole with a soap film over the top. I found out that when gas molecules are heated they. 12

13 LT 3 Formative Assessment Grade:«grade» Subject:Science Date:«date» 13

14 1 When a thermometer is cooled, the red liquid inside the thermometer moves down. This is mainly because: A B C D Cold liquids sink so the color falls in the thermometer The molecules move faster, and get a little further apart allowing the liquid to lower Hot liquids are lighter so the liquid moves down the thermometer. The molecules of the liquid move slower and get a little closer together. 14

15 2 When you heat a sample of a solid, the particles that make up the solid: A B C D Get bigger become more dense move faster slow down 15

16 3 If you put food coloring in room termperature water, the coloring spreads throughout the water. The water causes the color to spread mainly because: A B C D The water molecules are warm The water molecules are in motion The water molecules are attracted to the food coloring. The water is more dense that the food coloring. 16