In this DIY fire extinguisher science experiment kids will mix two simple kitchen ingredients together to make a small flame go out. This is a quick and impressive kitchen science experiment that will not be forgotten!
Why does a candle go out when you blow on it?
One of the possible explanations is that when you exhale you breathe out a lot of carbon dioxide. That carbon dioxide displaces the oxygen around the fire, making it go out. Some fire extinguishers even use carbon dioxide (among other chemicals) to put out larger fires.
In this experiment we made our own fire extinguisher using vinegar and baking soda. The reaction of these two materials produces carbon dioxide, which you can see bubbling up through the solution. Carbon dioxide is heavier than air so it drops right on top of our candle to put the flame out.
DIY Fire Extinguisher
- A sturdy bottle (preferably glass)
- A funnel
- A small candle
- 5 Tbsp vinegar
- 1/2 Tbsp baking soda
- Have an adult light the candle.
- Add vinegar to the bottle.
- Using a funnel, quickly drop the baking soda into the bottle.
- Being careful not to spill the mixture, hold the bottle at an angle so the carbon dioxide can flow out onto the fire.
- Notice how carbon dioxide is heavier than air and drops right onto the flame to extinguish it!