In: Chemistry
Why does the chemical potential change with pressure even if the system is incompressible (that is, remains at the same volume when pressure is applied)?
The variables that characterize a thermodynamic system, such as volume, pressure, particle number, chemical potential, temperature and entropy are not independent of each. A given thermodynamic potential, for example chemical potential can be written as a function of the three variables, P, T and N.
But if we consider chemical potential as a function of T only for an incompressible system, then it is not an independent state function as the the characteristics of an ideal gas cannot be defined using T and chemical potentials as independent variables. The concept of an ideal gas is an extreme case and none of the real systems has the chemical potential as a function of T only, and the chemical potential is a function of P as well.