Make your own fire extinguisher

Make your own fire extinguisher

Use chemistry to put out a fire.

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How could a simple chemical eaction put out a fire?

Watch this video to find out:

Here's how you can make one. Make sure you ask for help from your parents and never leave candles unattended.

What you need:

  • Candles
  • Matches
  • Jug
  • Vinegar
  • Bicarbonate of soda

How to:

  1. Light the candles - ask a parent or guardian for help.
  2. Add several tablespoons of bicarbonate of soda to the jug.
  3. Pour white vinegar into the jug and mix.
  4. Tip the jug slightly and move it over the candles. Make sure the liquid doesn't touch the candles.

Did you see the candles go out? How did it happen? You've just  made your own fire extinguisher.

How it works:

The vinegar and bicarbonate of soda react to form carbon dioxide. This is heavier than air and so stays in the jug when the jug is upright. When you tip the jug, the carbon dioxide pours out.

Fire needs oxygen to burn. The air has around 20% oxygen. When you tip the jug, the carbon dioxide pours out and pushes oxygen out of the way. Without oxygen the candles go out.

Have a look at a red fire extinguisher. They work in the same way as your fire extinguisher, by using carbon dioxide to displace the oxygen that the fire needs to burn.