PURPOSE: To demonstrate dramatically that the volume of vapor is greater than the volume of the same amount of liquid.
DESCRIPTION: An air balloon is held on top of a liquid nitrogen bath. The volume of the air balloon decreases for two reasons: first, the volume of the gas shrinks according to Charles' law, and second, some of the air changes to liquid and shrinks considerably. Liquid nitrogen will readily cause oxygen to liquify, and even liquify some of the nitrogen in the balloon.
REFERENCES: (PIRA 4C30.30)
EQUIPMENT: Air balloon with styrofoam bucket of liquid nitrogen.
SETUP TIME: None.
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