Thermochemical Study on [La(Hsal)2·(tch)]·2H2O[Hsal=salicylate(C7H5O-3), tch =thioprolinate (C4H6NO2S-)]

• 来源期刊: 中国化学(英文版)
• 年，卷（期）: 2008,（12）
• 页码范围: 2155-2160
• 页数: 6页
• 语种: 英文

摘要

The product from reaction of lanthanum chloride heptahydrate with salicylic acid and thioproline,[La(Hsal)2·(tch)]·2H2O, was synthesized and characterized by IR, elemental analysis, molar conductance, thermogravimatric analysis and chemistry analysis. The standard molar enthalpies of solution of LaCl3·7H2O (s),[2C7H6O3 (s)], C4H7NO2S (s) and [La(Hsal)2·(tch)]·2H2O (s) in a mixed solvent of absolute ethyl alcohol, dimethyl sulfoxide (DMSO) and 3 mol·L-1 HCI were determined by calorimetry to be △sHΘm [LaCl3·7H2O (s), 298.15 K]=(-102.36±0.66) 10.mo1-1, △sHΘm [LaCl3·7H2O (s), 298.15 K]=(26.65±0.22)kJ·mol-1,△sHΘm [C4H7NO2 (s),298.15 K]=(-21.79±0.35) kJ·mol-1 and △sHΘm {[La(Ksal)2·(tch)]·2H2O (s), 298.15 K]=(-41.10±0.32)KJ·mo1-1. The enthalpy change of the reaction LaCl3·7H2O (s) + 2C7H6O3 (s) + C4H7NO2S (s)=[La(Hsal)2·(tch)]·2H2O (s)+3HCl (g)+5H2O (1) (Eq.1) was determined to be △rHΘm=(41.02±0.85)kJ·mol-1.From date in the literature, through Hess' law, the standard molar enthalpy of formation of [La(Hsal)2·(tch)]·2H2O(s) was estimated to be △fHΘm {[La(Ksal)2·(tch)]·2H2O (s), 298.15 K]=(-30170.0±3.7)KJ·mol-1.