Consider gases described by the equations of state: (a) p = RT/Vm and (b) p = a/Vm 2 Use the relation (S/V)T = (p/T)V to derive an expression for (S/V)T for each equation of state. For an isothermal expansion, compare the change in entropy expected for a perfect gas and for a gas obeying the van der Waals equation of state: which has the greatest change in entropy and how can this conclusion be rationalized?