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Name: Kim
Status: Educator
Age: 30s
Location: N/A
Country: N/A
Date: 2000-2001

What is a good junior high science experiment on the topic of dewpoint?

Kim -

Have you tried the 2 liter bottle/cloud chamber experiement. It is a good example of condensation at the dew point, but you must first explain adiabatic cooling... not too hard.

Raise the humidity in the bottle by adding a little water and sealing the top. Squeeze the bottle causing it to adiabaticly warm and therefore hold more of the water in a vapor form. Release the pressure on the bottle causing the temperature to drop adiabaticly and ... Poof!...condensation. The saturated air must give up some of its water because it has cooled to the dew point.

Try it... you'll like it.

Larry Krengel

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