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Clara Phillips Dawes Elementary
3810 W. 81st Pl.
Chicago, Ill. 60610
Grade level 3
To become aware of the natural circulation of water from oceans, lakes and
rivers by evaporation into the air.
To know that condensation occurs to produce rain falling to the soil, running
off to rivers, lakes and then to the ocean once again.
A teakettle, about 18 inches of tubing, a clear glass bottle with a narrow neck,
ice, a pan large enough to contain both the bottle and ice water, and a heat
source. NOTE: These materials should be used by the teacher.
1. The lesson will begin with a review of cloud formation. The science textbook
has stated that clouds are made up of tiny drops of water. Our experiment will
help to prove this fact. On the chalkboard there is a chart naming and defining
some of the clouds: cirrus clouds, cumulus clouds, stratus clouds, and nimbus
2. There will be a discussion of the three steps in the water cycle:
evaporation, condensation and precipitation.
The sun causes water to evaporate. The moisture meets colder air and condenses
forming clouds. When droplets in a cloud are too heavy the water falls to the
earth as precipitation.
3. Do the following experiment:
Pour a pint of water into the kettle and attach the tubing to the spout of the
kettle as airtight as possible.
Place the other end of the tube in an empty bottle.
Place the bottle with the tube in a pan, pack ice around the base of the bottle.
Boil the water in the kettle until you see a few drops of water collecting
inside the bottle.
The energy from heat speeds up water molecules and some move so rapidly
that they evaporate or escape into the air as gas or water vapor. As more
molecules rise they push into the tubing and pass through it to enter the
bottle, which has been cooled by the ice. At that stage the cold air slows down
the gaseous water molecules and they come together or condense, once again
returning to the liquid state.
On earth there is a natural circulation of water from oceans, lakes and
rivers by evaporation into the air. Then condensation occurs to produce rain
falling to the soil, running off to the rivers, lakes and then to the oceans