Measurements of self-diffusion coefficients of the nitrate ion in aqueous solutions of potassium nitrate and calcium nitrate

Abstract

Self-diffusion coefficients of nitrate ions in aqueous solutions of potassium and calcium nitrate have been measured at 298.2 K over the concentration range 0.001–0.5 mol dm–3 using a diaphragm cell with 15NO–3 as tracer. Activation energies for the self-diffusion of nitrate ions in 0.01 and 0.1 mol dm–3 potassium nitrate and calcium nitrate solutions have also been determined from measurements at temperatures from 278 to 308 K. These are compared with those for ammonium ions.