Electrical Conductivity Measurement for Estimation of Standard Gibbs Energy Change of Ternary Oxide Formation

Abstract

Electrical conductivity measurements are used here to estimate the Gibbs energy change for formation of ternary oxide from binary oxides. The theoretical background and the advantages of the present method are discussed. As a demonstration, the standard Gibbs energy change of the reaction,
(Remark: Graphics omitted.)
was estimated by electrical conductivity measurements of two kinds of SrCrO₄ oxides, one equilibrated with Sr₃Cr₂O₈ and the other with Cr₂O₃. The standard Gibbs energy change of the reaction is obtained as
ΔG°⁄kJ mol⁻¹=−409+0.252T(±10), 1323∼1373 K.
The resulting value is in good agreement with that obtained by measurement of the equilibrium oxygen pressure using a solid oxygen concentration cell.