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.