Standard electrode potential of sodium

Abstract

From measurements of the cell Na(s); NaI (in dimethylamine); Na(0.0651 % amalgam) and the cell Na(0.0651 % amalgam); NaCI(0.05 or 0.1 m), AgCI(s); Ag(s), the standard electrode potential N a(s); Na+ over the temperature range of 5° to 40° C was obtained with the aid of values of the standard electrode potential of the silver-silver chloride electrode, previously determined by Harned and Ehlers, and of the activity coefficients of solutions of sodium chloride, previously determined at 25° C by Brown and MacInnes. The activity coefficients were corrected to the other temperatures by the use of data on heats of dilution determined by Gulbransen and Robinson. The final results were expressed by the equation EO = 2.71324+0.0007532(t-25) +0.000000688(t-25)2. Values of changes in free energy, entropy, and heat content accompanying the reactions corresponding to various combinations of the cells were calculated.