Corresponding States for Perfect Liquids

Abstract

On the basis of certain assumptions concerning the properties of the molecules, and by using classical statistics, the van der Waals theory of corresponding states is derived. No mathematical approximations are involved. Argon, krypton and xenon, which conform closely to the assumptions, show the expected correspondence in behavior and are taken as standards. The name perfect liquid is suggested for this behavior. In a second part, the deviations from perfection are discussed for a wide variety of substances. Particularly considered are heat capacities and entropies of vaporization which should be compared at points where the vapor to liquid volume ratio has the same value. The observed deviations are explained in a general way.