Condensation

Condensation is the opposite of evaporation. It happens when water vapor in the air cools down. The gas then becomes tiny drops of liquid water. You see condensation on cold drinks and foggy windows.

How Condensation Happens

Warm air can hold lots of water vapor. When that air touches something cold, it cools down fast. Cold air cannot hold as much vapor. So the extra water turns back into liquid drops. These drops stick to whatever cooled the air.

Condensation in Nature

Clouds are made by condensation high in the sky. Water vapor cools and forms tiny drops around dust. When many drops join, they fall as rain. Morning dew on grass is also from condensation. Your breath looks foggy on a cold day for the same reason.

Fun Facts

• Fog is just a cloud that has formed near the ground.
• Condensation on a mirror makes a good drawing surface.
• Eyeglasses fog up when warm breath hits the cold lenses.

Did You Know?

Clouds can hold millions of gallons of water, all formed from the tiny process of condensation.