Watch this short video to learn how make your own invincible balloon!

Items you'll need:

  • Balloon
  • Bamboo skewer

Science behind the experiment

The balloon is made from latex, a material made up of long, joined-together strands of molecules, called polymers. These molecules can stretch really well, which is why the balloon can expand as air is forced in.

When the balloon is blown up, the molecules are less stretched at the top and bottom of the balloon. So, as you push the skewer in, molecules can stretch around it, stopping the balloon from popping.

Top tip: You might want to add a few drops of vegetable oil to your skewer.

Key Terms:

  • Polymers – polymers are long chain molecules that can be made by chemical processes, such as plastics, and also occur naturally in living things e.g. wool and DNA.
  • Molecules – a molecule is a particle made up of two or more atoms that are chemically bonded together.

Activities and Questions

Does it make a difference if the balloon is fully or partially inflated?

Before blowing up the balloon draw dots on it a little smaller than a 5p coin. When you inflate the balloon you will see the hidden stresses in it, at what position is the balloon most stretched?

Can you push the skewer through the sides of your balloon instead? Place some sticky tape on the sides of the balloon to help and push the skewer through the tape. Why does the tape help?