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The Fireproof Balloon

Want to try an experiment involving water, fire, and a balloon?

First you'll need to blow up a balloon. Next, light a candle. What do you think will happen when you put the flame under the balloon?

It'll pop, of course. The flame will heat the rubber to the point where it becomes weak and can't hold up under the pressure from the air inside. But what happens when you add water to the mix?

Put about a quarter cup of water in the balloon and blow it up. Then light another candle. When you place the flame under the balloon, the balloon won't pop!

As long as the flame is beneath the water in the balloon, the water absorbs most of the heat and the rubber doesn't get very hot. Eventually the water will get hot enough to break the rubber.

Water has a really large specific heat, meaning that it takes a lot of heat to make water boil, and even more heat to make it vaporize. In fact, it takes about 540 calories of heat to evaporate one gram of water.

However, if you move the flame to another part of the balloon it will pop.

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