TRANSFERENCE – NUMBER MEASUREMENT OF SILVER NITRATE IN TETRAMETHYL UREA + WATER MIXTURE USING ELECTROMOTIVE FORCE METHOD

Abstract

An e.m.f. cell with transference similar in design to that developed by Rupert and recently by Braun Weingaertner has been fabricated. Using this cell, transference numbers of NO3‾ (tNO3‾ ) in AgNO3 have been measured in the concentration range 3.922× 10-4 to 11.2×10-3 mole dm-3 in 0.0606 mole fraction of tetra methyl urea (TMU) + water mixture at 298.15 K. The method is fast and reliable for transference number measurements of AgNO3 in mixed solvents. The transference number of NO3‾in the solvent mixture showed practically no change with a change in AgNO3 concentrations. The limiting transference number of NO3‾ (tْNO3‾) has been estimated by calculating the average of the transference number values of NO3‾ at different AgNO3 concentrations. Densities and specific conductivies of all solutions have been measured at 298.15 K. Values of Λ, the molar conductivity; have been used to derive the values of the molar conductivity at the infinite dilution (Λە).The value of Λە was then utilized to calculate the Walden product for the electrolyte in the solvent system at 298.15 K.