Electrical conductances of tetraalkylammonium and tetrabutyphosphonium bromides in isopropanol-water mixtures: Part I

Abstract

Conductances of dilute solutions of tetraalkylarnmonium halides (Me₄NBr, Et₄NBr, Pr₄NBr, Bu₄NBr, Pr₄NI and Bu₄NI) have been measured in <em>n</em>-PrOH-H₂O mixtures of varying dielectric constants (22.86 ≤ D ≤ 71.80) at 25ᵒC. The conductance data have been analysed using Fuoss-1978 (F-78) and Fuoss-Onsager-Skinner (FOS-65) conductance equations. The computed parameters of the F-78 differ significantly from those of the FOS-65. The significance of the limiting conductance (A₀), the association constant (<em>K</em>_A) and the cosphere diameter (R) has been discussed in interpreting the results in terms of the vital role of dielectric constant, viscosity and Walden product. The overall association behavior of these electrolytes is found to be consistent, although they prefer to form solvent-separated ion pairs in <em>n</em>-PrOH-H₂O mixtures.