The Air You Breathe

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Materials Needed:

• Two empty clean jars - Mark one A and the other B. 
• Two candles that can fit inside the jars. 
• A responsible adult to help with matches or lighter.    

Procedure

1. Leave out the jar marked A without a lid so that it will contain the air that is in the room.
2. Take jar B and hold it over your mouth for a minute so that it fills up with the air that you are breathing out.
3. Have your adult helper light the two candles. Look at the flames and make sure they are both burning evenly.
4. Place the jars over the two candles at the exact same time.
5. Watch what happens.

The candle that is in the jar that you breathed into should have gone out very quickly, much quicker than the other candle. This is because you already took out most of the oxygen in that jar by breathing into it. It was filled mostly by carbon dioxide which is what we exhale. The other candle stayed lit for a bit longer until it used up all of the oxygen in the jar.