Is water coming out of the air?

Yes, water can come out of the air!  It might sound strange, but it’s a natural process called condensation.

All you need to prove this is: empty tin can, ice, water, vegetable dye

Step 1: Remove the label from an empty tin can.
Step 2: Fill the tin can with ice and add water.
Step 3: Add a few drops of vegetable dye.
Step 4: Let it stand on the table for a short while.

What you will see: The tin can looks like it is “sweating,” for drops of water form on the outside.

Why: The drops are not colored and so they could not come from ice water leaking out of the can. The water comes from the air. Water vapor (water in the form of gas) in the air around the can has been cooled by the ice. The small particles of air, the air molecules, are slowed down when they become cold, so they move closer together (see chapter on heat) and change into liquid form. This is known as condensation. Clouds are formed when large numbers of these drops of water collect on dust particles as the air is’ cooled. The drops fall to earth, as rain or snow, when they become too heavy to be held up by the pressure of air.

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