Acid-Base Reactions in Fused Salts

An oxide ion acceptor or acid will react with certain oxyanions in fused salts to produce a new acid. The equilibria involved with pyro-sulfate and dichromate have been studied quantitatively in fused nitrates and, since nitronium ion is a very strong acid, other oxyions such as bromate and iodate may be studied in fused nitrate solutions. The self-dissociation of nitrate occurs t o a slight extent and has been studied quantitatively using an oxygen-oxide ion electrode. By making potentiometrlc measurements on both the basic and acidic nitrate solutions, one can calculate the self-dissociation constant. Strongly basic oxyanions, such as carbonate, can then be studied directly in regard to the oxide ion in equilibrium with the oxyanion in fused nitrates.