Etude thermodynamique du système albite-orthose par calorimétrie de dissolution et effusion de Knudsen couplée à un spectomètre de masse

Abstract

The enthalpy of mixing of the vitreous solution of albite and orthoclase were deduced from the thermal effects corresponding to the dissolution of albite, orthoclase and their mixtures in liquid lead metaborate at 970 K. The Gibbs energy of these mixtures was also determined by Knudsen-cell mass-spectrometry. The thermodynamic behavior of the system is characterized by weak negative departures from ideality.