Thermochemical Study of [Ce(Hsal)2·(tch)]·2H2O

• Published in: Journal of chemical and engineering data Vol. 55; no. 8; pp. 2874 - 2878
• Main Authors: Xu, Li, Sheng-Xiong, Xiao, Li-Juan, Ye, Ai-Tao, Li, De-Jun, Yang, Xia, Li, Qiang-Guo, Li
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 12.08.2010
• Subjects: Chemistry; Coordination compounds; Exact sciences and technology; Inorganic chemistry and origins of life; Preparations and properties; Non steroidal antiinflammatory agent; Salicylic acid; Pyrolysis; Hepatoprotector; Organic ligand; Thermodynamic analysis; Salicylates; Lanthanide Complexes; Heat of solution; Cerium Complexes; Hydrates; Timonacic
• ISSN: 0021-9568; 1520-5134
• DOI: 10.1021/je9010344

The reaction of cerium chloride heptahydrate with salicylic acid and thioproline produced [Ce(Hsal)2·(tch)]·2H2O [Hsal = salicylate (C7H5O3 −), tch = thioprolinate (C4H6NO2S−))], which was isolated and characterized by IR, elemental, chemical, and thermogravimetric analysis. The standard molar enthalpies of solution of [CeCl3·7H2O(s)], [2C7H6O3(s)], [C4H7NO2S(s)], and [Ce(Hsal)2·(tch)·2H2O(s)] in a mixed solvent of absolute ethyl alcohol, dimethyl sulfoxide (DMSO), and 3 mol·L−1 HCl were determined by calorimetry to be Δs H m Θ[CeCl3·7H2O(s), 298.15 K] = −(42.22 ± 0.37) kJ·mol−1, Δs H m Θ[2C7H6O3(s), 298.15 K] = (45.54 ± 0.37) kJ·mol−1, Δs H m Θ[C4H7NSO2(s), 298.15 K] = (21.91 ± 0.60) kJ·mol−1, and Δs H m Θ[Ce(Hsal)2·(tch)·2H2O(s), 298.15 K] = −(30.87 ± 0.39) kJ·mol−1. The enthalpy change of the reaction CeCl3·7H2O(s) + 2C7H6O3(s) + C4H7NO2S(s) = [Ce(Hsal)2·(tch)]·2H2O(s) + 3HCl(g) + 5H2O(l) was determined to be Δr H m Θ = (263.12 ± 0.95) kJ·mol−1. From data in the literature, through Hess’s law, the standard molar enthalpy of formation of [Ce(Hsal)2·(tch)]·2H2O(s) was estimated to be Δf H m Θ[Ce(Hsal)2·(tch)·2H2O(s), 298.15 K] = −(2785.7 ± 3.2) kJ·mol−1.