STUDY OF THE EFFECT OF ETHANOL ON THE CONDUCTIVITY OF POTASSIUM NITRATE AT DIFFERENT TEMPERATURES

Precise measurements on the conductivity of Potassium nitrate in pure water and ethanol-water mixed solvent media containing 0.10, 0.20, 0.30, 0.40, 0.50, 0.60 and 0.70 volume fractions of ethanol at temperatures 303.15, 308.15 and 313.15 K are reported. The concentrations were varied from ~ 0.010 to ~ 0.10 mol.L -1 . The results showed a sharp increase in the conductivity with increasing electrolyte concentration. The increase in the conductance with concentration is due to an increase in number of ions per unit volume of the solution. The decrease in conductivity with increase in the amount of ethanol is due to the reduction of relative permittivity of the ethanol-water mixed solvent phase and makes easier for the formation of ion-pairs in the solution phase.