A Note on the Study of the As₂ O₃-As₂O₅ Equilibrium in Glass

Abstract

Alkali-borate, phosphate, silicate and potash-lead-silicate glasses of various compositions were melted with 0.5% As₂ O₃ in electric furnace at different temperatures for different' periods. Total and pentavalent arsenic contents of these glasses were estimated chemically. With the progress of heating, a steady state between tri and pentavalent arsenic was attained. The ratio As₂ O₃/As₂ O₅ at this steady state increases with the increase of melting temperature and acidity of the base glass. This ratio is largely determined by the base glass composition. Loss of arsenic was more rapid with increasing As³⁺ content.