THERMOGRAVIMETRIC STUDY OF MHgO2 (M=Ca, Sr, Ba) UNDER CONTROLLED OXYGEN AND MERCURY PARTIAL PRESSURES AND RELATED THERMODYNAMICS

摘要

A novel method of thermogravimetry under controlled mercury and pO2s was developed, which allowed authors to obtain the precise thermodynamical data for the equilibrium MHgO2(s) reversibly yields MO(s)+Hg(v)+1/2O2 (M=Ca, Sr, and Ba). Temperature dependencies of equilibrium constants Kp are described by the equations: log Kp(CaHgO2)=-(9424+-540)/T+(10.28+-0.57), (888-1013 K); log Kp(SrHgO2)=-(10197 +-890)/T+(10.10+-0.83), (1043-1118 K); log Kp(BaHgO2)=-(10474+-730)/T+(9.94+-0.64), (1098-1163 K). Thermal stability of mercurates increases in the order CaHgO2, SrHgO2, BaHgO2. 13 refs.