Conductance studies of alkali-metal chlorides and bromides in 2-methoxyethanol at 25 °C

Abstract

The conductances of a number of alkali-metal chlorides and bromides, MX(M+ = Li, Na, K, Rb, Cs and X-= C1, Br) have been measured in 2-methoxyethanol (ME) at 25 "C and the data have been analysed by the 1978 Fuoss Conductance equation in terms of the limiting molar conductance AO, the association constant, KA and the association distance, R.Single ion conductivities have been determined using Bu,NBPh, and Bu,NBBu, as reference electrolytes. Strong association was found for all these salts in ME and the limiting conductances (Ao) were in the order Li > Na < K < Rb < Cs and C1 > Br. Evaluation of Stokes radii indicates that NaCl and NaBr form ion pairs with fully solvated ions while in other cases some solvent molecules are perhaps included in the ion pair.2-Methoxyethanol (ME) has attracted much attention in recent years as a solvent medium for various electrochemical investigations. ' Although a number of precise conductance measurements of alkali-metal halides in other solvents are known in the literat~re,~-' relatively few studies of such a nature have been made in 2-methoxyethanol. In this paper an attempt has been made to reveal the nature of ion-solvent interactions of alkali-metal halides with 2-methoxyethanol through the measurement of their conductances at 25 "C. Since transference number data for solutions of these salts are lacking in ME, single ion conductivities have been evaluated using two reference electrolytes, uiz. Bu,NBBu, and Bu,NBPh,, in an effort to provide reliable values of ionic mobilities.

Study of Ion−Solvent Interactions of Some Alkali Metal Chlorides in Tetrahydrofuran + Water Mixture at Different Temperatures

“…Alkali metal chlorides (Fluka) were of purum or puriss grade and purified by us as described earlier. , …”

Ionic Association of Some Lithium Salts in 1,2-Dimethoxyethane. A Raman Spectroscopic and Conductivity Study

“…Recently, we have initiated a program − to study Li + ion solvation in different nonaqueous solvents from conductometric, viscometric, and laser Raman spectroscopic measurements. The study has now been extended to 1,2-dimethoxyethane (DME), a solvent particularly relevant for battery construction using lithium electrodes.…”

Volumetric, acoustic, optical, and viscometric properties of binary mixtures of 2-methoxyethanol with aliphatic alcohols (C1-C8)

“…It is an ether alcohol showing physicochemical characteristics midway between protic and dipolar aprotic solvents. As a result, it has attracted much attention as a solvent in electrochemical studies (Nandi et al, 1989; Franchini et al, 1986Franchini et al, , 1989Franchini et al, , 1990. Excess thermodynamic properties of the binary mixtures of 2-methoxyethanol have been reported earlier (Chandak et al, 1977;Marchetti et al, 1991).…”