Reactivity of Metal Oxides

摘要

Thermodynamic analysis of defect formation at the reaction temperature of metal oxides with sulfur is undertaken. The reactivity of the constant is characterized by the Schottky constant at the reaction temperature. A formula is given for the Gibbs energy, permitting its calculation from the change in #alpha# and in the lattice periods and the relative change in temperature up to the reaction temperature. The temperature coefficient of linear expansion is determined from the initial temperature of reaction of the oxides with sulfur and carbon. The theoretical reaction temperatures of some oxides with sulfur and various compounds are presented. It is suggested that the number of defects has the determining influence on the character of the reaction, the quality of the reaction products, and the direction of the reaction. The difference in reactivity of the reactants may be responsible for the selectivity of catalysts in catalysis. This is relevant to Taylor theory. A discrepancy is observed between the reactivities of the oxides with sulfur at the temperature where intrinsic conductivity sets in; this indicates a vacancy mechanism of sulfide formation.