The First Law: Work, Heat and the Ratio of Heat Capacities

Control console

Set the piston to a series of indicated volumes at constant temperature and record the pressure.

Gas

Indicated volume

cm³

pwrmeasfault

Select the gas and set the thermostat. Allow two minutes for equilibration (the apparatus does this automatically).
Record the pressure at eight or more indicated volumes spanning the full travel.
Plot 1/P against the indicated volume V. The result is a straight line of gradient 1/(nRT) and intercept V_0/(nRT).
Obtain the amount of gas n and the dead volume V_0 from the gradient and the intercept.
Compute the work done by the gas in expanding between your first and last volumes, and hence the heat absorbed.

standby

No readings on this channel yet. Set the controls and press Record pressure.

A fresh page. Take your first reading and it will be entered here.

Take at least one reading to plot.