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Charles' Law
Procedure
One balloon is inflated with helium, another with air. The helium balloon is
attached to a weight so it doesn't float away. Both balloons inserted into containers
filled with liquid nitrogen. The helium balloon will shrink to a fraction of
its original size, the oxygen balloon will shrink to a smaller size.
Discussion
Charles' Law predicts a fourfold decrease in the volume of a gas as it is
chilled from room temperature, 20 degrees Celsius, to liquid nitrogen temperature,
-196 degrees Celsius. If the gas in the balloon condenses, as oxygen gas does
at -183 C, the volume change is much greater. The density of liquid oxygen
at -183 C is 1.149g/ml, and that of the gas at 0 C is 1.429g/liter. Therefore,
the volume of the balloon can shrink by a factor of more than 700.
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