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.