Homemade Fire Extinguisher

The Scientist of the Week creates a homemade fire extinguisher using a chemichal reaction. She puts a layer of baking soda on a plate. She stands a short candle and a tall candle in the baking soda. When she pours in some vinegar, which candle will go out first?

When vinegar is combined with baking soda, the two react and produce carbon dioxide gas. The carbon dioxide gas is heavier than the surrounding air so it sinks into the bottom of the bowl. As the reaction continues, more and more carbon dioxide gas is produced which begins to slowly fill up the bowl. When the level of carbon dioxide has risen to the level of the flame, the flame will go out from lack of air.