화학공학소재연구정보센터
Thermochimica Acta, Vol.531, 60-65, 2012
Heat capacity, enthalpy and entropy of SrBi2O4 and Sr2Bi2O5
Heat capacity and enthalpy increments of ternary strontium bismuth(III) oxides SrBi2O4 and Sr2Bi2O5 were measured by the relaxation time method (2-210K), DSC (253-352K) and drop calorimetry (570-1072 K). Temperature dependencies of the molar heat capacity in the form C-pm =161.97 + 45.936 x 10(-3) T - 1.7862 x 10(6)/T-2 J K-1 Mol(-1) and C-pm = 197.48 + 87.463 x 10(-3) T - 1.9282 x 10(6)/T-2 J K-1 mol(-1) for SrBi2O4 and Sr2Bi2O5, respectively, were derived by the least-squares method from the experimental data. The molar entropies at 298.15 K, S degrees(m)(298.15 K) = 206.1 +/- 1.1 J K-1 mol(-1) for SrBi2O4 and S degrees(m),(298.15 K) = 261.2 +/- 1.4 J K-1 mol(-1) for Sr2Bi2O5, were evaluated from the low temperature heat capacity measurements. (C) 2012 Elsevier B.V. All rights reserved.