Standard Gibbs energies of formation of SrCrO4 and Sr3Cr2O8

Abstract

The electromotive force of oxygen concentration cell, Pt, O2(SrCrO4, Sr3Cr2O8, Cr2O3)|Y2O3-stabilized ZrO2|O2 (air), was measured at temperatures between 1073 and 1423 K. The tensiometric measurement on the reaction of SrCO3+2SrCrO4⇄Sr3Cr2O 8+CO2+(1/2)O2 was carried out at temperatures between 980 and 1300 K. From these results, the standard Gibbs energy of formation of SrCrO4 and Sr3Cr2O8 have been obtained as ΔGf(SrCrO4)o/kJ mol-1=-1493+4.17×10-1T (±3) and ΔGf(Sr3G2O8)o/kJ mol-1=-3598+9.38×10-1T (±7), respectively.