Conductance of Asymmetric Iodides of Butyl-Triethyl-Ammonium in Toluene-Acetonitrile Mixtures at 25°C

Abstract

The conductance of ter-BuEt₃ NI, sec-BuEt₃ NI, iso-BuEt₃ NI, n-BuEt₃ NI and Bu₄ NI in toluene acetonitrile mixtures has been measured. The range of dielectric constant of the solvent mixtures covered from 9,4 to 35,9. The densities and viscosities of the solvent mixtures were also determined. The phoreograms of the ter-BuEt₃ NI and sec-BuEt₃ NI in the mixtures having molar fractions of toluene of 0,4, 0,5 and 0,6 and those of the iso-BuEt₃ NI and Bu₄ NI in the molar fractions 0,3, 0,4 and 0,5 show similar shape. The phoreograms lie below the Onsager limit line. The conductance data for the salts having asymmetric cations were analyzed using the Fuoss Onsager equation for unassociated 1–1 electrolytes. The data for the salt n-BuEt3NI in mixtures of mole fraction 0,1, 0,2 and 0,4 of toluene were fitted to the equation. All other systems studied did not fit. This investigation suggests that the geometry of the hydrocarbons chains has an effect on the conductance behaviour of ammonium salts.

Key Words:

• Fuoss-Onsager equation
• mixed solvents
• acetonitrile
• toluene
• asymmetric tetraalkylammonium salts