Materials Required:
l Round balloon
l Scissors
l Newspaper
l Matches
l Glass jar with a narrow mouth
The help of one of your parents
Procedure:
- Cut off the top half of a round balloon and discard it. You will be left with a solid piece of rubber.
- Fold a piece of newspaper to approximately 3 by 5 inches. Ask one of your parents to light the newspaper with a match and place the burning paper into the glass jar.
- Quickly place the piece of rubber over the jar’s opening. Use both hands to securely hold the rubber against the glass sides, grasping opposite edges of the balloon and gently tugging with a slight outward and downward motion. You will see the balloon stretch upward at first. Then the rubber will turn inward until it bursts with a loud bang.
This Is What Happens:
The burning paper heats the air inside the jar, which causes the air to expand. This is why the balloon first bulges out. After the flame dies, however, the air cools and its pressure is less than the air outside the jar. The outside pressure pushes the rubber down and breaks it.
