Observe what happens. Light candle No. 2. Arrange the corks in a triangle around its base and place the glass on the corks. Observe what happens. Repeat the procedure with the remaining candles and the glassware behind them.
Students observe the behavior of the flames.
Several students can be timekeepers and data recorders. Teacher and students compare observations. Discuss and conclude that both fuel and air were necessary to maintain the flame. The teacher pours 6-8ml of hydrogen peroxide into a test tube. The yeast will react with the hydrogen peroxide releasing oxygen.