Engage/Elicit:

Where do you think rain and snow come from?

ART: Cartoon of boy and girl from story in a cloud, sprinkling water from watering cans to make rain.

Explore:

Materials

• Two clear plastic cups per group.
• Freezer

Procedure

1. Put one plastic cup in the freezer and keep one out. Note the time.
2. What will happen to the glass jar while it's in the freezer?
   TEXTBOX
3. When warm air comes in contact with the cold cup, what do you think will happen to the air?

   L5 Type your response in the text box above. L4 Think about how the temperature of the air changed when it comes in contact with the cold glass. L3 When the air comes in contact with the cold glass, the temperature of the air will ______. L2 Choose from the options above. O When the warm air touches the cold glass, it will gain energy and warm up. O When the warm air touches the cold glass, it will lose energy and cool down. L1 The cold glass will draw heat from the air and the air will get cooler. Explain the cooling of the air in your own words.

4. Check the time. If the plastic cup has been in the freezer for at least 5 minutes, take the cup out of the freezer. Place it next to the cup that has been at room temperature.

   Library: plastic-condense.JPG

   
   Draw and describe what you see.

   Background image: Empty plastic cup & draw tool

   L5: Write your response in the box above. L4: Consider in what ways the cold cup looks different than the cup at room temperature? L3: The cold cup looks... compared to the cup at room temperature. L2: The O cold O room temperature cup looks frostier. L1: The cold cups looks cloudy. Be sure to show and label the differences between the cups.

   (Hide until previous question answered)

5. From our previous experiment, what can you tell me the cloudiness is made of?

   L5: Write your response in the box below. L4: Think of why it looks "cloudy." L3: The cloudiness is made of .... vapor. L2: The cloudiness is made of (*water vapor, dust, air). L1: The cloudiness is made of water vapor. How do we know?

   Explain:

   The water vapor in the air can turn back into liquid water when it loses heat. When a substance turns from a gas to a liquid it is called condensation.

   animation or model on macro level of condensation

How does water get out of the air to form liquid droplets in clouds?

L5: Write your response in the box below. L4: What happens to the water vapor in the air to make it turn back into liquid water? L3: When the water vapor in the air loses... it turns back into liquid water to form the droplets in clouds. L2: When the water vapor in the air (gains energy, *loses energy, gets heavier) it turns back into liquid water to form the droplets in clouds. L1: When the water vapor in the air loses energy, it turns back into liquid water to form the droplets in clouds. Explain.

The glass jar referenced in the Exploration should not have liquid in it, because if it does it may freeze and shatter the jar. Posted by azucker at Aug 07, 2007 14:32

The other reason the jar should not have water is that kids may think the water in the jar is the source of the condensate. Note: this jar could be put in a frig, not a freezer, I think. I'll try it.   Posted by ehazzard at Aug 09, 2007 11:04