Thermodynamic study of the vaporization of cerium orthophosphate

Abstract

The high temperature Knudsen cell mass spectrometric technique has been used to study the vaporization behaviour of solid cerium orthophosphate over the temperature range 1700–1850 K.

From the second- and third-law analyses of the equilibrium reaction: CePO₄(s)= CeO₂(g)+ PO₂(g), the following standard heat of formation of CePO₄(s) has been derived: ΔH^°_298,f[CePO₄(s)]=–1898.5 ± 31.5 kJ mol^–1. These results are discussed and compared with those obtained by other authors for other LnPO₄ compounds.