Electrical conductivities of alkylammonium chlorides in water at 25C ut to 3000kg/cm2

Abstract

The conductivities of dilute aqueous solutions of mono-n-propyl-, di-n-propyl-, mono-n-hexyl-, and mono-n-octylammonium chlorides were measured at 25℃ as a function of pressure. The limiting equivalent conductivities of the alkylammonium salts were determined by the Fuoss-Onsager equation up to 3000kg/cm^2 (1kg/cm^2=0.9678×10^5 Pa) and the limiting equivalent conductivities of the alkylammonium ions were obtained up to 2000kg/cm^2, using the transference numbers by Kay et al. and the conductivities by Nakahara et al. for aqueous KCl solutions. The limiting equivalent conductivity of each salt has a maximum against pressure, while that of the corresponding cation decreases monotonously with increasing pressure like the methyl and the ethyl substituted ammonium ions studied previously. The Walden products of these alkylammonium ions at infinite dilution decrease with increasing pressure. The negative pressure coefficient of the Walden product of the alkylammonium ion leads us to the conclusion that the water density in the vicinity of the alkyl group is higher than in the bulk.