Campaign - Decorating with Science

Decorating With Science

Every party needs balloons. Use the gaseous power of science to fill them up!


• Balloons, uninflated

• Baking soda (1/3 cup per balloon)

• Funnel

• Water bottles, 16-ounce size

• Vinegar (1 cup per bottle)


  1. Collect empty water bottles — one for each balloon you plan to use.
  2. Pour approximately 1 cup of vinegar into each bottle.
  3. Using a funnel, fill each uninflated balloon with 1/3 cup of baking soda.
  4. Place the opening of each balloon over the mouth of a water bottle (be sure it fully covers the mouth), and allow the balloons to hang over the side of the bottle, so that the baking soda does not drop in.
  5. Count backwards from 10 to 1 and then lift each balloon, shaking the baking soda into the bottle. Watch as the chemical reaction causes the balloons to expand.
  6. Place the bottles around the room to use as decorations and get the party started!

The Science Behind It

Why did the balloons inflate after the baking soda mixed with the vinegar? Vinegar and baking soda mixed together create a chemical reaction. Vinegar is an acid (think lemons) and baking soda is a base (think bleach). The chemical reaction is an acid-base reaction, which creates carbon dioxide. It is this carbon dioxide gas that inflates the balloon. Maybe you even saw bubbles of carbon dioxide as the ingredients mixed together! Now inflate a balloon on your own and tie it closed. Remove one of the decoration balloons (ensuring it stays blown up) and tie that one closed. Play with the balloons and compare which one falls to the floor more quickly. Carbon dioxide is heavier than the gas mixture in our breath, so the decoration balloon likely hit the ground first.

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