Make a fireproof balloon

Make a fireproof balloon

Will the balloon burst?

What you need:

  • Balloon
  • Water
  • Lighter
  • Safety goggles

How to:

This experiment uses fire, so ask an adult for help. Make sure you wear safety goggles. It could get messy, so it's best to do this experiment outside!

  1. Half fill the balloon with water.
  2. Blow some air into the balloon.
  3. Tie a knot so the balloon is secure.
  4. Hold a lighter underneath the balloon, where the water is, for a few seconds. What happens?

Have a look at this video to see what's going on:

What's happening:

Why does the balloon with no water burst? The rubber of the balloon without water gets so hot that is becomes too weak to resist the pressure of the air inside the balloon. The balloon bursts with a bang!

It takes a lot of heat to change the temperature of water. When the balloon has water in it, the water absorbs most of the heat from the flame. This means that the rubber doesn't get as hot, so the balloon doesn't burst.