Question

A sample of 1.0 mol of a monoatomic ideal gas is taken through a cyclic process of explanation and compression as shown in fig. What will be the value of $△H$ for the cycle as a whole?

Answer 1

Enthalpy or H is a state function, which means it does not depend on the path of the process, how it is carried out. Instead, it depends on the intial and final state of a process and changes accordingly.

In the following cyclic $(1\to 2\to 3\to 1)$ process, the intial and final point is the same $(i.e.1)$.

Hence the enthalpy change or $△H=0$, which indicates there is no change in enthalpy when we comes back to state 1 via following a cyclic path from state 1.