Question 2: (a) For a system with the internal energy, U=(AVNS5)1/2 where S is the entropy, A is the Helmholtz free energy, V is the system volume and N is the total moles in the system. Find the Gibbs free energy and the enthalpy of the system. [5] Q6) Calculate B2(T) for n-octane vapour at 0.215MPa and 427.85K. Assume n-octane follows van der Waal's EoS and at this T and P three-body interactions does not prevail. Given: Tc=569.4K and Pc=24.97bar. [5]