Fireproof Balloon Experiment | Why Fire Won’t Pop This Balloon

This is an interesting experiment with balloons and lighted candles. Hold an inflated balloon over a lighted candle, but it won’t burst. Although it is hard to believe, there is a secret to it. The inflated balloon is not empty. There is water inside. Has your brain started flickering now? Let us proceed to explain more about the fireproof balloon experiment.

Materials required

Balloon – 2 numbers
Candle – 1 number
Matchbox – 1 number
A glass of water

Steps to follow

1. Inflate a balloon, and tie a knot at the end.
2. Place a candle on a table, and light it.
3. Hold the inflated balloon right above the flame.
4. In just a few seconds, there will be a bang, and you will have a popped balloon in your hands.
5. Now take the next balloon, and fill it with water.
6. Inflate the water-filled balloon, and tie a knot.
7. Hold the balloon over the flame.
8. Did it pop? No, the balloon is withstanding the heat of flame for quite a while.
9. Examine the portion of the balloon which was held over the flame. What do you see? It is all black from soot. Fire has shown its effect, but not by bursting the balloon.

What we learn

So why did the balloon pop when there was just air inside, and why didn’t it pop when filled with water? When the normal balloon was kept over the flame, the heat from fire caused a portion of the latex to melt. Melted part of the balloon could not hold the pressure of the air inside, and so it popped.

Now, what difference did it make when there was water inside the balloon? Water is a great conductor of heat. It absorbed the heat from the surface of the balloon. Principles of convection also came to play here. Convection, in simple terms, is the circular motion that happens in a fluid when heated.

When the warmer fluid becomes less dense and moves up, the colder fluid which is denser, moves down. In our experiment, the heated water close to the surface of the balloon moved upwards, and the colder water from top replaced it. This water again absorbed the heat from latex. As a result of this continuous process, the balloon did not burst.

If you are interested in reading more about balloon experiments, visit our Experiments section.

Here’s Something You Might Like

As a participant in the Amazon Associates Program, Science4Kids may earn from qualifying purchases.