Experiment 9: Hydrogen Balloon Explosion

I find hydrogen and oxygen interesting, especially when they combust.  In this experiment, I ignited a balloon filled with pure hydrogen gas.  To make the gas, I placed 0.6 grams of magnesium powder in a balloon and then placed the balloon on the top of an Erlenmeyer flask filled with 50 mL of 1.0 molar hydrochloric acid.  When I tipped the balloon to allow the magnesium powder to contact the acid, the reactants reacted to form magnesium chloride and hydrogen gas.  Since the reaction is exothermic, it grew quite warm.  After I tied the balloon off, I taped a candle to a yardstick and lit the candle.  If you want more gas, and thus more fun and danger (whee!), you should use more acid and more magnesium.  In this video I show the results, using my lit candle to ignite my very awesome gas: