This activity will demonstrate the formation of condensation and will
show that there is water vapor in the air even though it is not visible.
Time requirement: 20 minutes as an activity, 15 minutes as a
- Source of water
- 2 beakers of equal size
- Ice cubes
- Stir stick
- Clock with second hand
- Fill each beaker with equal amounts of water. Be sure to leave enough
room to add ice.
- Record the temperature of the water.
- Add one ice cube at a time to one to the beakers. Stir with the
- Continue to add ice to the one beaker and stir until moisture appears
on the outside of the beaker.
- Record the amount of time required and the temperate of the ice
- Why does moisture appear on one beaker and not on the other?
- Where did the moisture come from that appeared on the side of the
- What was the difference in temperature between the two beakers?
- Why do you sometimes observe dew on the grass when you leave your
house in the morning?
- In certain areas (like the Pacific Coast where Stanford is located)
fog forms overnight and "burns off" during the morning hours. Why does
Last updated: September 04, 1997
Joe Twicken /