A STUDY OF COMPLEX IONS IN FUSED SALT SYSTEMS. Final Report

Absorption spectrophotometric methods were used in a study of complex ion formation and acid-base reactions in fused chloride and nitrate systems. Several methods for the treatment of spectrophotometric data were investigated. The spectra of various chromium salts were determined in three nitrate melts and in fused lithium chloride-pothssium chloride. In low solute concentrations in LiNO/sub 3/-KNO/sub 3/, NaNC/sub 3/-KNO/sub 3/, and LiCl-KCl melts, the species found was the chromate ion, while in molten AgNO/sub 3/, the species found was the dichromate ion. An explanation of these observations is put forward, and their significance discussed. Formation constants for leadchloro and lead-bromo complexes were evaluated. The values obtained for the first two lead-chloro and leadbromo complexes are 11.3, 3.6 and 13.3 and 6.0, respectively. Mass spectral studies of the gaseous products of the reaction between dichromate ion and nitrate ion in fused NaNO/sub 3/-KNO/sub 3/ showed that the reaction is of an acidbase type, involving formation of a nitronium ion which then reacts with nitrate ion to evolve dinitrogen pentoxide decomposition products. A number of qualitative experiments in fused salts involving acid-base reactions were performed, and their relation to oxidation-reduction processes in the fused salts is discussed. An analogy is drawn to a similar relation in aqueous solution. (auth