School of Physics Lecture Demonstration Manual

Ha-3 Absolute Zero Demonstration

Published: Monday 13 March 2006 - Updated: Monday 28 March 2011


To demonstrate that absolute zero is approximately -273°C



Click on pictures to enlarge.

Absolute Zero Diagram


An approximate value of absolute zero may be obtained by plotting pressure versus temperature and extrapolating the line produced to zero pressure.

In use the bulb is submerged successively in boiling water (100°C), ice water 0°C, and dry ice in alcohol (-78.5°C) and the corresponding pressure indicated by the gauge, recorded.

Safety notes

Chemical Safety 

Fire/Burn Safety 

Sharps Safety 


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