Conductance studies of ion association: N-etbyl-4-cyanopyridinium iodide in mixed binary nonaqueous solvent at 20°C

Abstract

Conductances of N-ethyl-4-cyanopyridinium iodide have been measured in concentration range (1.21- 28.43) x 10^-4 mol dm^-3 in acetonitrile + acetone, ethanol + acetone and ethanol + acetonitrile mixtures at 20&deg;C. The conductance data in all cases have been analysed by the Shedlovsky equation to obtain A₀ and <em>K_A </em>value for the electrolyte. The influence of the solvent composition on the various equilibria present in the solution is obtained from the <em>K_A</em> values. The composition dependence of the Walden product gives information about the solvation of ions. The limiting molar conductance (A₀) values in pure organic solvents and in binary mixture of dipolar aprotic solvents have been split up into the limiting ion conductances (&lambda;₁⁰). The average solvated radii of the ions are precisely computed. The results are compatible with the solvent composition dependence of the Walden product.