Play with the Christmas lights.
Material
- candles
- matches
- pitcher,
- vinegar
- bicarbonate (baking soda)
Instructions
- Step 1: Light the candle. Pour a few decilitres of vinegar into the jug.
- Step 2: Add a few teaspoons of baking soda and stir.
- Step 3: Gently tilt the jug towards the candle, without letting the liquid out. Do you manage to extinguish the candle?
What happened?
When you add the soda to the vinegar, a chemical reaction happens. The reaction forms water and carbon dioxide gas. The gas is heavier than air and sinks downwards. We can’t see the gas, which makes it look magical. When you tilt the jug towards the light, some of the gas comes out, because the gas is heavier than air it pushes the air down and smothers the flame. Carbon dioxide gas is a product of combustion, therefore carbon dioxide gas does not burn, but manages to extinguish the candle. Other gases, like oxygen, have a property of keeping the fire alive. For example, when you blow on a fire, it burns better because you add oxygen to the fire.
Air contains 21% oxygen and the air we breathe out contains 16% oxygen.
Idea from Heureka Experimentfabrik.