Chronopotentiometric diffusion coefficients of silver(I) in molten KNO₃-Ba(NO₃)₂ eutectic

Abstract

The application of chronopotentiometry as an electroanalytical technique for the in situ determination of silver(1) in molten KNO₃-Ba(NO₃)₂ (87.6 : 12.4 mole%) eutectic has been described. Reduction of silver(1) on platinum microelectrode is found to be a reversible, single-step one-electron process. Diffusion coefficients, D (cm² s^-l), of silver(1) in the melt have been determined and its temperature variation in the range 578-697 K could be expressed by the relation (R = 8.314 J K^-1 mol^-1): D = 0.913 x ^10-3 exp(-19810/RT) Effect of the presence of the divalent Ba²⁺ cations in the fluid on the diffusion process has been discussed.