The Magic of Evaporation

So far as we know, living things need water. Water is a very special substance, and it has unique properties.

Water is made of light, small, hydrogen and oxygen atoms. These small water molecules can escape into the air.

Have you noticed these things?

If you leave a glass of water on a shelf somewhere, after a while the water will disappear.

If you hang up a wet towel, it will be dry in a few hours.

If you spill water and don't wipe it up, it will go away somehow.

People say . . . the water has evaporated. What does this mean?

In The States of Matter we saw that materials can exist in different states on earth: Water can exist in all three forms:

• Solid: ice
• Liquid: liquid water
• Gas: water vapor