A piston cylinder assembly contains 1 kg of nitrogen gas. The gas expands from an initial state where T1 = 700 K and P1 = 5 bar to a final state where P2 = 2 bar. During the process the pressure and the specific volume are related by Pv1.3 = constant. Assuming ideal gas behavior and neglecting kinetic and potential energy effects, determine the heat transfer in kJ, using
a. Constant specific heat evaluated at 300 K
b. Constant specific heat evaluated at 700 K
c. Data from table T-11.