Solutions of electrolytes in liquid ammonia. Part V. Ion-pair formation by ammonium nitrate and ammonium iodide in liquid ammonia at –40 °C

Abstract

Ion-pair and triple ion formation constants (KA and KT) have been obtained for NH4NO3 and NH4I in liquid ammonia at –40 °C from previously reported activity coefficient measurements. For NH4NO3, KA= 401 ± 9 dm3 mol–1 and KT= 11·4 ± 0·7 dm3 mol–1, and for NH4I, KA= 476 ± 20 dm3 mol–1 and KT= 6·5 ± 0·8 dm3 mol–1, when the size parameter in the Debye–Huckel equation is set at the Bjerrum critical distance (16·22 × 10–10 m). Revised activity coefficients based on this analysis are presented.