The Electrical Conductivity of Supercritical Solutions of Sodium Chloride and Water

Abstract

A description is given of the method used to measure the electrical conductivity of NaCl in steam at steam densities between 0.2 and 0.4 g/cc. Values of the specific and equivalent conductances are tabulated at 378, 383, 388, and 393°C for various NaCl concentrations at different steam densities. Sodium chloride behaves as a weak electrolyte at all steam densities used. Estimates of the ion‐pair dissociation constant K, based on Shedlovsky's method, indicate that K decreases from about 9×10^—3 to 6×10^—7 as the steam density decreases from 0.4 to 0.2 g/cc. Preliminary results for cesium chloride and hydrogen chloride in steam indicate that cesium chloride is comparable in strength with sodium chloride, but that hydrogen chloride is a much weaker electrolyte.