Properties of Matter

Alka-Seltzer Rocket

Enrichment Activity for 5-11 11-14

What you need

  • An Alka-Seltzer tablet
  • An empty film canister
  • Old newspaper
  • Water


  1. Put the tablet in the film canister. Add about 1cm of water
  2. Put the lid on, lightly shake the canister
  3. Quickly place it upside down on the newspaper and stand back!

Results and Explanation

The Alka-Seltzer fizzes when in water, releasing gas. This gas builds up in the canister until the pressure is too great and the lid is forced off!

These experiments have not been specifically safety tested for home use but we believe them to be safe if the instructions are followed. Adult supervision or direction is recommended as appropriate. All experiments are carried out at your own risk.

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