Are rubber molecules less bouncy when cold

Find two rubber balls that bounce to about the same height. Put one ball in the freezer section of a refrigerator. Leave the other ball out in the room. Wait about four hours. 

Take the ball out of the freezer. Stand on a hard floor. Hold a ball in each hand. Hold your arms straight out and drop both balls. Drop both balls several more times. 

Which ball bounces higher How high does the colder ball bounce How high does the warmer ball bounce Does the warmer ball still bounce after the cold ball stops Count the number of bounces for each ball. 

A rubber molecule is a special type of molecule called a polymer. Polymer molecules are made of thousands of smaller molecules. The smaller molecules are joined together to make long chains. One long chain makes a single polymer molecule. 

Some polymers are very rigid and stiff, like a plastic bottle. Other polymers are very flexible and can be stretched like a rubber band. Long chains of rubber molecules in a rubber ball can be pushed together 

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ARE RUBBER MOLECULES LESS BOUNCY WHEN COLD ... 

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