... number of moles of dry air, mol nw ϭ number of moles of water vapor in moist air sample, mol nws ϭ number of moles of water vapor in saturated moist air sample, mol Moist air is a binary mixture of ... mass of dry air, for the sake of consistency, air density a, in lb/ft3 (kg/m3), should be defined as the ratio of the mass of dry air to the total volume of the mixture, i.e., the reciprocal of ... enthalpy of moist air at initial state and enthalpy of saturated air at end of ideal adis abatic saturation process, Btu/lb (kJ/kg) w1,w* ϭ humidity ratio of moist air at initial state and humidity...