Conductance and viscosity measurements of some 1 : 1electrolytes in dimethylformamide plus methanol mixtures at 25, 30 and 40 degrees C

Molar conductances and viscosities of some 1:1 alkali metal and tetraalkyl ammonium salts have been measured in dimethylformamide (DMF) + methanol (Me OH) mixtures containing 100, 89.3, 69.1, 49.6, 29.9 and 10.7 mol% DMF and p ure MeOH at 25 degreesC. The conductance data have been analysed by Shedlov sky method setting ion - size parameter equal to Bjerrum critical distance suggested by Justice to calculate Lambda (o) and K-A Calculation of limitin g ionic conductances and solvated radii shows preferential solvation of ion s in these mixtures. The viscosity data have been analysed using the Jones Dole equation. The ion - solvent interaction parameter, viscosity B - coeff icients have been found to be positive for all the electrolytes in all the systems. The ionic B(+/-)coefficients have been evaluated,by taking Bu4NBPh 4 as reference electrolyte. Conductances and viscosities of three salts, Na Br, NaBPh4 and Bu4NBr, have been measured at 30 and 40 degreesC in differen t solvent mixtures. The limiting ionic conductances and ionic viscosity B - coefficients for the ions show decreased solvation with increase in tempera ture.