Question

A piston contains 160 moles of an ideal monatomic gas that initally has a pressure of 1.9 × 105 Pa and a volume of 3.6 m3. The piston is connected to a hot and cold reservoir and the gas goes through the following quasi-static cycle accepting energy from the hot reservoir and exhausting energy into the cold reservoir.
The pressure of the gas is increased to 4.9 × 105 Pa while maintaining a constant volume.
The volume of the gas is increased to 10.6 m3 while maintaining a constant pressure.
The pressure of the gas is decreased to 1.9 × 105 Pa while maintaining a constant volume.
The volume of the gas is decreased to 3.6 m3 while maintaining a constant pressure.

It may help you to recall that CV = 12.47 J/K/mole and CP = 20.79 J/K/mole for a monatomic ideal gas, and that the number of gas molecules is equal to Avagadros number (6.022 × 1023) times the number of moles of the gas.

Answer 1

I think the correct answer from the choices listed above would be the first option. For the system above, the pressure of the gas is increased to 4.9 × 105 Pa while maintaining a constant volume. Hope this answers the question. Have a nice day.