Kristen Gerstberger

The Fireproof Balloon

Science Concept-Water absorbs heat.

Materials-

• two balloons
• several matches
• water

Directions-

• Blow up one of the balloons and tie the end.
• Blow up the second balloon and fill it halfway with water.
• Light a match and hold it under the balloon filled with air. The balloon will pop.
• Light a second match and hold it under the balloon filled with water. (The match must be held under the water filled portion of the balloon.) The balloon with water will not pop.

Introduction- Who knows what a balloon is made of? What do you think will happen to the rubber balloon if I were to hold a lit match underneath? (Demonstrate) I have a second balloon that has a small amount of water in it. What would happen to this balloon if I held another match underneath? Lets take a vote - How many people think the balloon will pop? How many think the balloon will not change? Lets find out who the experts are!

Explanation- The balloon that is filled with air only popped because the flame from the match heated the rubber balloon causing the material of the balloon to weaken. The weakened balloon cannot resist the pressure caused by the air inside the balloon, and as a result, the balloon popped. The second balloon containing water does not pop, because the water inside the balloon absorbs the heat from the match. Therefore, the heat does not concentrate on the rubber of the balloon causing the balloon to weaken and pop. The balloon with water is able to resist the pressure of the air inside the balloon and it remains inflated.

Reference- "Science is Fun in the Lab of Shakhashiri" Internet, http://scifun.chem.wisc.edu/HOMEEXPTS/FIREBALLOON.html