Point e is chosen so that it is on the saturated liquid line with = 100 kJ/kg. It corresponds roughly with = 13 bar and = 108 K. Throttling from this point to a pressure of 1 bar ends in the two-phase region (point f). This means that a mixture of gas and liquid leaves the throttling valve. Since the enthalpy is an extensive parameter, the enthalpy in f () is equal to the enthalpy in g () multiplied by the liquid fraction in f () plus the enthalpy in h () multiplied by the gas fraction in f . So