Electrostatic contribution to the thermodynamic properties of air

Abstract

A general method is developed and applied to investigate, theoretically and numerically, the effect of interparticle electrostatic forces on the thermodynamic properties and equilibrium composition of air over temperatures from 400 to 100,000 K and log ($\text{ϱ}\text{ϱ}{}_{\mathrm{SL}}$) from −6.5 to + 3.0. Standard statistical mechanics procedures, with necessary adaptations, are employed. Three results are indicated: (1) the electron concentration determined without consideration of electrostatic forces must be increased (70% maximum); (2) at T > 35,000 K and log $\text{(}\text{ϱ}\text{ϱ}{}_{\mathrm{SL}}\text{> 2.0}$, an unstable thermodynamic state is indicated; and (3) the change in thermodynamic properties for stable states, as a result of electrostatic force effects is small.