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Sunshine Activities


Gas Expansion Activity

The gas expansion activity gives new meaning to the "big bang" theory!

Certain gases expand when exposed to heat. This experiment with helium balloons and hot summer days will show you how -- and how much.

What You'll Need:

  • Helium balloons
  • Hot day

Fill four balloons with helium at your local party or craft store. Ask the clerk to fill one half-full, one three-quarters-full, one just right, and one a little too full.

Be sure your car is running and has the air conditioning on, and that the car is waiting at the entrance of the store when you come out.

Once you get home, rush the balloons inside the cool house. One by one, take the balloons outside, starting with the half-full balloon, and watch what happens.

You'll see just how helium expands with heat and what that expansion does to the latex in balloons.

Quench everyone's thirst with the refreshing activity on the next page!

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