I'm quite confused about isochoric and isobaric irreversible processes, and, in particular, the doubt is about work W in such processes.
If the processes is reversible (that is I can write $d W= p dV$) I have no problem in saying that
- In a isochoric process $W=0$, since $dV=0$.
- In a isobaric process $W=p(V_b-V_a)$ since $\int p dV=p \int dV$.
In other words, in both cases I can be sure that work is a state function (and, in particular, in isochoric is zero).
The problem is: I find in different textbooks that the previous expression for $W$ are used also in the cases of irreversible processes.
But in my view this is not correct because, to reach those conclusions about work it is fundamental to use $d W= p dV$, which holds true iff the process is reversible.
So are the previous relations correctly or incorrectly used in the case of irreveresibility?
If so, can you suggest me any book/source that talks about canonical processes (isobaric, isochoric in particular) without saying that for any isochoric and isobaric process (irreversible or not) the previous ones are the expressions of work?