SOME ENERGY RELATIONS IN THE SYSTEMS PbO‐B2O3 AND PbO‐SiO2*

Abstract

AbstractHeats of solution of a series of glasses in the system PbO‐B2O3 were measured in 2 N nitric acid with a simple vacuum‐bottle calorimeter. Heats of solution of a series of glasses in the system PbO‐SiO2 ranging in composition from 6 to 35% of SiO2 were measured in a mixture of HF and 2.5 N nitric acid with an electrically calibrated isothermal jacket calorimeter. From these data and heats of fusion available in the literature, calculations were made of the heats of reaction of the component oxides in either amorphous or crystalline states in forming glasses in these systems.