Question

a) True or false: The equilibrium value of any unconstrained internal parameter in a system

that is in contact with a thermal and pressure reservoir minimizes the Gibbs potential.

b) What does the concavity of the entropy surface S(U,V,N) imply about the concavity vs.

convexity of the energy surface U(S,V,N)?

Answer 1

Note: As per regulations we can only provide solution to one problem at a time. As you have not listed which problem to solve i am providing solution to first problem i.e. true false problem.

(a) True. This is clearly the definition of Gibbs Potential minimum principle which states that the equilibrium value of any unconstrained internal parameter in a system that is in contact with a thermal and pressure reservoir minimizes the Gibbs potential at constant temperature and pressure.