PURPOSE: To demonstrate liquification of nitrogen gas by adiabatic expansion.
DESCRIPTION: An air liquefier consists of a tiny coiled tube through which compressed air passes before expanding adiabatically as it leaves the tube. The cooled air circulates around the coiled tube, pre-cooling the air before it leaves the tube. In a few minutes liquid nitrogen drips down and collects on the inside of a glass tube which surrounds the entire device.
REFERENCES: (PIRA unavailable.)
EQUIPMENT: Joule-Kelvin cooling device mounted on nitrogen tank.
SETUP TIME: 5 min.
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