1. Water in the Air  When water drops form on a cold glass, the water comes from the air around the glass.  Water vapor is water in the form of a gas.  The amount of water in the air is called humidity.  Liquid water becomes a gas called water vapor through the process of evaporation.  The change from a gas to a liquid is called condensation.

2. Water in the Air  When cool and warm air meet, the lighter warm air is pushed higher in the atmosphere.  Whenever warm air rises and cools, the water vapor in the air condenses.  Water droplets in the air form clouds.  Transpiration is the process that plants use to add water vapor to the atmosphere.

3. “Cloud in a Jar” Experiment  How is the process creating a mini cloud similar to the way real clouds are formed?  How is the process of creating a mini cloud different from the way real clouds are formed?  Did you see any precipitation in the jar? If so, what caused it?  Where in the jar did evaporation, condensation, and precipitation occur? Discuss the following questions with your group then record your response in your science notebook.

4. Water in the Air – Vocabulary  Water vapor – water in the form of a gas  Humidity – the amount of water vapor in the air  Evaporation – the changing of a liquid into a gas  Condensation – the changing of a gas into a liquid