The Statistical Mechanics of Condensing Systems. II

It is shown how the quantities entering into the equations for the thermodynamic functions of a saturated vapor, given in the previous article, may be calculated. It is necessary to evaluate certain integrals which enter into the final expressions as the terms of an (almost) infinite, but rapidly convergent series. The first two of these integrals have been evaluated with fair accuracy for a gas obeying the inverse seventh power law of force attraction. The third integral has been estimated. The coefficients with which these integrals enter into the final expression have also been estimated. The results of the calculation have been compared with the experimental values for CO2 and CH4. Specifically, the volume of the saturated vapor in units of the volume of the molecules, and the ratio (PV)/(RT) for the saturated vapor have been calculated on an arbitrary temperature scale. The agreement between the calculations and the experimental values is not unencouraging.