Density Effect on the Electric Conductivities of Monovalent Ions in Methanol along the Liquid-Vapor Coexistence Curve

Abstract

For a better understanding of the molecular transport mechanism in fluids, it is important to study the density dependence in the intermediate region between liquid and gas. The hydrodynamic theory is considered to explain the molecular transport coefficients at high liquid densities, while the binary collision theory is valid in dilute gases. In this article, we report the density dependence of the electrolyte conductivities of alkali-metal halides in liquid methanol near the liquid-vapor coexistence curve up to the critical temperature (240°C) and those of tetraalkylammonium bromides up to about 180°C, and discuss the application limit of the hydrodynamic theory (Hubbard-Onsager’s dielectric friction theory) for the ionic transport process in liquids.