INFLUENCE OF GLASS COMPOSITION ON REDUCIBILITY OF Ag+, Bi3+, Sb3+, AND PP+*

The reducibility of a number of ions by dry hydrogen was studied in various glass compositions. Reduction temperatures with dry hydrogen were about 75° C, lower than with wet hydrogen. The glasses contained 5.0% of Sb₂O₃, Bi₂O₃, or PbO or 0.1% of Ag₂O. In all of the glasses, silver ions were reduced at lower temperatures as basicity was increased, while an increased ratio of B³⁺ to O^2- or Si⁴⁺ to O^- increased stability. The reducibility of Bi³⁺, Sb³⁺, and Pb²⁺ are not easily interpreted. Silver showed reduction at approximately 130°C., bismuth at 200°C., lead at 350°C., and antimony at 400°C.