and 0.90

Molar conductivities of dilute solutions of sodium chloride in binary mixtures of 2-methylpropan-2-ol and water were measured in the temperature range from 288.15 to 308.15 K at 5 K intervals. The limiting molar conductivity (Λo) and the ion-pair formation constant (KA) were determined by the Lee-Wheaton conductivity equation. Thermodynamic quantities, Gibbs energy (ΔG°), enthalpy (ΔH°) and entropy (ΔS°), for the ion-association reaction were derived from the temperature dependence of KA. The activation enthalpy of the charge transport (ΔH*) was derived from the temperature dependence of Λo. The obtained thermodynamic quantities, together with Walden product, were discussed in terms of solvent basicity, structure permittivity and viscosity