You have 0.4 mol of gas A within a piston–cylinder assembly. The initial pressure is 20 bar, and the initial temperature is 675 K. The system then undergoes an adiabatic process where the piston expands against constant external pressure of 1 bar until the forces balance.

(a) What is the fi nal temperature of the system?

(b) How much work is done during the process?
You may assume gas A behaves as an ideal gas during this process. In checking the lab notes for data for gas A, you come across the following experiment that was performed on a closed system containing pure gas A within a rigid container. The container was connected to a heat source (in this case a resistance heater) and was otherwise well insulated. As a known amount of heat, Q, was provided through the resistive heater, the temperature, T, of the system was measured. The following data were collected for one mole of species A: