1. What is the minimum amount of work required to separate 1mol of air at 27°C and 1atm pressure (assumed to be composed of 1/5 O2 and 4/5 N2) into O2 and N2, each at 27°C and 1atm pressure?
2. Prove that:
(a) Td(A/T) = -(U/T)dT - PdV + Σuj dnj.
(b) d(PV) = SdT + V dP + Σnj duj.