Finding Absolute Zero

Finding Absolute Zero Aim: To find absolute zero

Apparatus: A tripod A Bunsen burner A stand A flask Water A thermometer A barometer

Diagram: An empty flask attached to a barometer

A thermometer

A beaker filled with water

A stand

A tripod A Bunsen burner

Method: Heat the water with a Bunsen burner. Stop heating and wait for the water to start cooling down. Start the thermometer and barometer. Wait for them to take enough measurements.

From the theory TP, find when P=0. That is supposed to be the absolute zero value.

Results: I cut out some of the result which seemed unnecessary. Temperature Pressure 89.8 113.98 70.4 105.16 88.4 113.27 69.5 104.72 87 112.63 68.8 104.53 85.3 112.11 67.7 104.23 84.2 111.34 66.3 103.54 82.7 110.71 65.4 103.19 81.4 110.12 64.5 103.02 80.2 109.43 63.3 102.5 79 109.04 62.6 102.28 78 108.4 61.7 102.12 76.6 107.79 60.4 101.8 75.5 107.31 59.1 101.49 74.5 106.82 58.5 101.3 73.4 106.51 57.9 101.08 72.3 105.91 56.3 100.7 71.5 105.62 55.3 100.52

Graph:

Conclusion: According to my calculation, the pressure is zero when T=-193.81. In theory, 0K=-273 so the error is 29%.

Evaluation: I think the error is too big. The graph should have got a gentler slope. I think we should have waited for more results because the slope was getting gentler in the end. Also, I shouldn’t cut out the last part of the results.