A simple kinetic theory of gases

Abstract

One of the important features of classical thermodynamics is that it has very few independent quantities that need to be ‘explained’ in terms of the structure of matter. The thermodynamically reversible behaviour of all systems with two degrees of freedom can be described in terms of the equation of state and one principal heat capacity. For a closed hydrostatic system the principal heat capacities are C _p and C _V , the heat capacities at constant pressure and constant volume, respectively, and the equation of state is a relation between pressure p volume V and temperature T for equilibrium states. Therefore, for a microscopic description of a closed hydrostatic system it is only necessary to describe in terms of the structure of matter either C _p or C _V and any two of p, V and T. All other equilibrium properties of the system may be derived from these by thermodynamic reasoning.