In the following lake CV = 5 and CP = 7(Btu)(Jb mole)-1(oF)-1 for nitrogen gas:
(a) Three pound moles of nitrogen at 70(oF) contained in a rigid vessel, is heated to 350(oF). How much heal is required if the vessel has a negligible heal capacity? If it weighs 200(Ibm) and has a heat capacity of 0.12(Btu)(Ibm)-1(oF)-1, how much heal is required?
(b) Four pound motes of nitrogen at 400(oF) is contained in a piston / cylinder arrangement. How much heal must be extracted from this system, which is kept al constant pressure, to cool it to 150(0F) if the heat capacity of the piston and cylinder is neglected?