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The nano powders of LaCrO3 were prepared by a sol-gel route. The heat capacity of LaCrO3 nano powders from 350 to 550 K was measured by DSC method and expressed as: Cp (LaCrO3) (±0.112) = 166.844 – 8.500 × 103T – 1.022 × 106T 2 (J/(mol?K)) (350-550 K). An EMF measurement assembly was developed with CaF2 as an electrolyte for the gal- vanic cell. From measured EMF data of the reversible cell, () Pt, La2O3, LaF3, O2 (1 atm)|CaF2|O2(1 atm), LaF3, LaCrO3, Cr2O3, Pt(+), and the relevant value of Gibbs free energy, the Gibbs free energy of formation of LaCrO3 was calculated from 700 to 885 K: G fΟ,L aCrO3= 1555.364 + 0.354T (kJ/mol) (700-885 K). And the Gibbs free energy change of reaction from simple oxides La2O3 and Cr2O3 was calculated to be: G fΟ,o x(LaCrO3)= ?94.758 + 8.530 × 102T (kJ/mol) (700-885 K).
The heat capacity of LaCrO3 nano powders from 350 to 550 K was measured by DSC method and expressed as: Cp (LaCrO3) (± 0.112) = 166.844 - 8.500 × 103T - 1.022 × 106T 2 (J / (mol · K)) (350-550 K). An EMF measurement assembly was developed with CaF2 as an electrolyte for the gal- vanic cell. From measured EMF data of the reversible cell, Pt , La2O3, LaF3, Cr2O3, Pt (+), and the relevant value of Gibbs free energy, the Gibbs free energy of formation of LaCrO3 was calculated from 700 to 885 K: G fO, L aCrO3 = 1555.364 + 0.354 T (kJ / mol) (700-885 K). And the Gibbs free energy change of reaction from simple oxides La2O3 and Cr2O3 was calculated to be: G fO, ox (LaCrO3) =? 94.758 + 8.530 102T (kJ / mol) (700-885 K).