The electrical conductivities of NH4Cl and MenNH4-nCl(n=1,2,3) in water

Abstract

The electrical conductivities of NH_4Cl, MeNH_3Cl, Me_2NH_2Cl and Me_3NHCl in water were measured at 25℃ up to 3000kg/cm^2 from about 5 to 50×10^-4 N. The limiting equivalent conductivities of the salts at high pressure were determined from the Fuoss-Onsager equation and the limiting equivalent conductivities of the component 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 pressure coefficients of the Walden product of the ammonium ions studied are negative at normal pressure and the pressure dependence of the Walden product becomes stronger as the methyl group increase. This would suggest that both the decrease in the electrostatic interaction and the increase in the interaction between the methyl group and water make the ionic Walden product reduce with increasing pressure, and that the density of water about the methyl group would be larger than that of the bulk water.