Vinegar and Baking Soda Fire Extinguisher

The Seasons

(Chemistry for ages 8+)

If you’ve done lots of science experiments at home, you have probably done at least one with vinegar and baking soda, such as building a volcano, blowing up a balloon, or making a rocket take off. Did you know this acid and base reaction can also put out a fire?

It turns out there are endless ways to use chemical reactions for everyday needs. The video above demonstrates a simple activity to observe the firefighting properties of chemistry. Here’s what you’ll need:


Matches or lighter
Baking soda
Napkin or cloth cover (optional)
Adult supervision (Adult supervision at all times please)


  1. Start by lighting your candle with a match or lighter. Be very careful when doing so and be sure the candle is in a safe place when you light it. Always have an adult help when experimenting with fire.
  2. Next, sprinkle some baking soda into the cup. Add enough to coat the bottom of the cup, or about 1 tablespoon.
  3. Add some vinegar to the baking soda. Pour just a little so the reaction does not overflow from the cup, or about 1/8 cup. You should see the mixture fizz up immediately as the baking soda and vinegar combine. Cover the cup with the napkin or cloth to trap the gases being released from the fizz. If you do not have a napkin or cloth handy, your hand should do the trick.
  4. Once the reaction is over (no more fizzing), slowly and carefully remove the cover (or your hand) from the cup. Slowly lift the cup and tilt it over the flame of the candle. Do NOT tilt the cup so much as to pour out the liquid, but just enough to release the gases trapped in the cup. Did your candle go out?


A fire needs three things to keep burning: heat (the match or lighter you used to light the candle), fuel or something to burn (the wick of the candle), and oxygen (the air we breathe).

When you create the acid-base reaction between the vinegar and baking soda, the fizzing bubbles are actually due to the release of carbon dioxide (an invisible gas). When you trap this gas and pour it over the flame, the fire loses access to oxygen because it is surrounded by the air of a different gas, the carbon dioxide.

Though this is a handy trick to remember, having a real and certified fire extinguisher is the best way to fight a small fire rather than reaching in your kitchen cupboard for baking soda and vinegar.