For N2 gas, Cp,m is nearly constant at 3.5R = 29.1 J/(mol K) for temperatures in the range 100 to 400 K and for low or moderate pressures. (a) Calculate q, w, ?U, and ?H for the reversible adiabatic compression of 1.12 g of N2 from 400 torr and 1000 cm3 to a final volume of 250 cm3. Assume perfect gas behavior. (b) Suppose we want to cool a sample of N2 gas at room temperature and pressure (25 ?C and 101 kPa) to 100 K using a reversible adiabatic expansion. What should the final pressure be?