English: Both containers of gas start at the same pressure, volume and temperature (left side). Then the containers are heated differently to the same temperature T2 (right side). The top container is heated at constant pressure with the heat Qp and the bottom container is heated at constant volume with the heat QV. Although both containers have the same end temperature the heat required is different. Since the heating at constant pressure also involves an increase in Volume, the added heat Qp has to both raise the temperature of the gas and do work on the piston. Thus Qp will always be more than QV.