(2)内能、焓及熵的变化量 The change in Internal Energy, Enthalpy and Entropy dg=c, dr+ pdy du d =c, dr dh=c dt The amount of heat added to a closed system during a constant volume process equals to the increase in internal energy. 定容过程中加入闭口系统的热量等于系统的内能的增 加量q c dT pdv  = v + du = q = cv dT dh = c p dT (2)内能、焓及熵的变化量 The change in Internal Energy, Enthalpy and Entropy The amount of heat added to a closed system during a constant volume process equals to the increase in internal energy. 定容过程中加入闭口系统的热量等于系统的内能的增 加量