The Meaning of Condensation

Why do clouds form? What causes cold glasses to sweat on a hot day? Why do sunglasses fog up when moving from an air-conditioned building into a very hot day? The answer to all these questions is condensation. It happens around us all the time, and without it, our water cycle would fail. Our water sources would dry up. Condensation serves an important function.

Function

Warm air containing water in its gaseous form, vapor, eventually meets up with something cool such as the upper atmosphere or the side of our soda can. When it does, the water vapor turns from a gas to a liquid as the water molecules in the air come together and condense into droplets forming condensation.

Significance

Condensation is an important part of the water cycle. The sun warms bodies of water causing water to evaporate into the air. As the water vapor rises and meets cooler temperatures, it condenses, forming clouds.

Features

Condensation requires a reduction in temperature of a gas. Warmer molecules move quickly and spread themselves farther apart. When cooling occurs, molecules slow down and move closer together forming condensation.

Types

Distilling depends on condensation. During distillation, specific temperatures cause a liquid to separate turning part of it into vapor that is then allowed to condense so that it can be collected.

Dew and Frost

Another form of condensation is dew. Meteorologists measure the dew point, which is the temperature at which the air has cooled sufficiently to allow the water vapor to form condensation, or dew, on any surface. If the temperature is below freezing, the dew is called frost.

Resources

• Condensation and the water cycle