Oxygen is part of the fire triangle (oxygen, heat, and fuel). Without it, there’s no fire. This basic “fire extinguisher” puts out a candle flame by depriving it of oxygen. Because this experiment involves fire, ask for adult supervision.

For a printable version of this project, click here.

• Birthday candle

• Matches

• Clean, empty tuna can

• Baking soda

• Large bowl

• Vinegar

1. Ask an adult to do this step. Hold a lit match to the base of the candle. Drip some melted wax into the centre of the tuna can. While the wax is still soft, push the base of the candle into it, so that the candle stands up in the centre of the can.

2. Light the candle.

3. In the bowl put one tablespoon of baking soda and three tablespoons of vinegar. This will bubble and produce carbon dioxide gas.

4. Slowly pour the carbon dioxide gas (but not the vinegar and baking soda!) over the candle flame.

5. Did the flame go out? If not, rinse out the bowl and try mixing a fresh batch of ingredients.