Learning about fire

We did experiments with candles last week.First we lit three candles , and put a small jar over one and a big jar over another.We left one uncovered.We saw that the uncovered candle burned longest and the candle covered by the small jar burned the shortest amount of time.We learned that fire needs fuel,air and heat  in order to burn .
Next we put water around a candle and then covered it.We saw bubbles and then the flame went out.The water then went into the jar.We heard that that is because air expands when hot.When the flame went out,the air didn t fill the jar as much and so there was room for the water to go in.