Answer:




Δ
Δ
Explanation:
Hello,
At the first state, the molar volume is:

The volume in both the second and third state:

Now, as it is about an adiabatic process, one remembers the following relationships:

- Next, for the aforesaid volumes and the first pressure, one computes the second pressure as:

- And the temperature:

- Q:
It is clear that the heat for the first process is 0 as it is adiabatic, but for the second one, it is computed as:

Then the total heat:

- The work for the first process is:

It is clear that the second process is isochoric, so the work here is zero, thus, the total work is:

- For the two processes, ΔU becomes the same value since the system returns to the initial temperature, so ΔU total is 0, thus, for each process, one's got:

- Finally, the total enthapy is also 0 due to same aforesaid reason, thus, each enthalpy is:

Best regards.