Standard molar enthalpies of formation of Ln(C 9H 6NO) 2(C 2H 3O 2) (Ln: Nd, Sm)

Abstract

Using an on-line solution-reaction isoperibol calorimeter, the standard molar enthalpies of reaction for the general thermochemical reaction: LnCl 3·6H 2O(s) + 2C 9H 7NO(s) + CH 3COONa(s) = Ln(C 9H 6NO) 2(C 2H 3O 2)(s) + NaCl(s) + 2HCl(g) + 6H 2O(l) (Ln: Nd, Sm), were determined at T=298.15 K, as −(56.9±1.4) and−(67.9±1.5) kJ mol −l, respectively. From the mentioned standard molar enthalpies of reaction and other auxiliary thermodynamic quantities, the standard molar enthalpies of formation of Ln(C 9H 6NO) 2(C 2H 3O 2)(s) (Ln: Nd, Sm), at T=298.15 K, have been derived to be: −(1494.7±3.3) and −(1501.5±3.4) kJ mol −l, respectively.