Viscositites and pair potential energy function for the argon–methane gas-phase interaction

Abstract

The viscosities of gaseous argon–methane mixtures have been measured in the temperature range 118–393 K using a capillary flow technique. The results are accurate to ±0.8%, and are used to calculate interaction viscosities and binary diffusion coefficients considered accurate to ±1.9%. The calculated properties are compared with experimental and calculated values of other workers. A spherically averaged intermolecular pair potential energy function is generated by inversion of the interaction viscosities, and compared with other isotropic and anisotropic potential functions for the Ar–CH₄ interaction. Second virial coefficients calculated from the potential function are shown to be in good agreement with experiment.