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Wonder why cans take up so much space? As heavy as they are when full, they are light and bulky when done with. What if you could make them really tiny, saving on recycling space? What if you could shrink them to a fraction of their volume? Try this experiment to see how this can happen.

• An empty aluminum soft-drink can
• A 2 or 3 quart (or 2 to 3 liter) saucepan
• A pair of kitchen tongs
• Water
• An adult’s supervision

1. First, fill the saucepan with cold water. Now, put 1 tablespoon of water into the empty soda can.
2. Here you will need an adult’s help. Okay?
3. Place the saucepan near the stove, so it’s easy to get to. Place the soda can onto a burner on the kitchen stove. The water in the can will soon boil, and you can tell when it’s boiling, because a cloud of vapor will escape from the opening of the can. Let the water boil for 30 seconds.
4. Using the tongs, grasp the can and carry it to the saucepan. Quickly turn it over and dip it into the water in the pan. The can should collapse right away!

How It Works:

When the water inside of the can came to a boil, it pushed the air out of the can. Water vapor replaced the air. When you inverted the can and emptied it into the cold water of the saucepan, the water vapor inside of the can was suddenly cooled, and it condensed, or got smaller. Then, the air pressure on the outside of the can was greater than the air pressure inside, and the can collapsed from the force of outside air pressure.