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Abstract: Crystal structure of n-decylammonium ethyl sulfate was determined by X-ray crystallography. Lattice potential energy and molar volume of the solid compound and its anion were respectively obtained. Ionic radius of the anion was calculated from the corresponding effective volume of the anion. Molar enthalpies of dissolution of the compound at different concentrations m /(mol·kg–1) were measured by an isoperibol solution–reaction calorimeter at T =298.15K. According to the Pitzer’s electrolyte solution theory, molar enthalpy of dissolution of the compound at infinite dilution () was determined to be (21.284±0.042) kJ·mol–1, and enthalpy of hydration of the anion SO4C2H5 − was calculated to be ΔH– =−340.68kJ·mol–1. The values of apparent relative molar enthalpies ( ΦL) of the title compound and relative partial molar enthalpies ( and ) of the solute and the solvent at different concentrations were derived from experimental values of enthalpies of dissolution of the compound. Finally, enthalpies of hydration of the compound and its anion were calculated by designing a thermochemical cycle in accordance with lattice potential energy and molar enthalpy of dissolution at infinite dilution. [Copyright &y& Elsevier]

Abstract: The crystal structure of 1-decylammonium hydrobromide was determined by X-ray crystallography. Lattice potential energy and molar volumes of the solid compound and its cation were obtained respectively. The ionic radius of the cation can be calculated from the corresponding effective volume of the cation. The molar enthalpies of dissolution of the compound at different concentrations m/(mol·kg−1) at T =298.15K were measured by an isoperibol solution-reaction calorimeter at T =298.15K. According to the Pitzer’s electrolyte solution theory, the molar enthalpy of dissolution of the compound at infinite dilution and Pitzer parameters ( and ) were obtained. The values of apparent relative molar enthalpies of the title compound and relative partial molar enthalpies ( and ) of the solute and the solvent at different concentrations were derived from the experimental values of the enthalpy of dissolution of the compound. Finally, hydration enthalpies of the compound and its cation were calculated by designing a thermochemical cycle in accordance with lattice potential energy and the molar enthalpy of dissolution of the title compound at infinite dilution. [Copyright &y& Elsevier]

• Trihydrated manganese lactate and anhydrous copper lactate were synthesized and the crystal structures were characterized by X-ray single crystal diffraction technique. • The lattice potential energy and ionic volume of the anion were obtained. • The enthalpies of dissolution of these complexes were measured and the infinite dilution enthalpies of solution and Pitzer's parameters were calculated. • The average hydration enthalpy of lactate ion was calculated. • The dehydration process of trihydrated manganese lactate complex were explored by TG-DSC technique Trihydrated manganese lactate Mn[(C 3 H 5 O 3) 2 (H 2 O) 2 ]⋅H 2 O(s) and anhydrous copper lactate Cu(C 3 H 5 O 3) 2 (s) were synthesized. Crystal structures of the two compounds were characterized by X-ray single crystal diffraction technique. The compositions, spatial structures and coordination modes of the two compounds were determined by analysis of their molecular structures and crystal structures. Lattice potential energies of the compounds were calculated by using the crystallographic data. Molar enthalpies of dissolution of these metal complexes in the ultrapure water were measured by an isoperibol solution-reaction calorimeter with an accuracy of ±0.3%. On the basis of Pitzer's electrolyte solution theory, infinite dilution molar enthalpies of dissolution and Pitzer's parameters of the two lactate complexes soluble in water at T = 298.15 K were calculated. The infinite dilution molar enthalpies ( Δ s H m ∞) of dissolution of the title compounds were combined with lattice potential energies (U POT) by a designed thermodynamic cycle, and the average molar enthalpy of hydration of the common lactate ion was calculated to be (407.207 ± 0.038) kJ·mol−1. The mechanism of thermal decomposition or dehydration of the trihydrated manganese lactate was explored by TG-DSC technique, and the difference between molar enthalpies ( Δ s H m) of dissolution of trihydrated manganese lactate and anhydrous copper lactate at the same concentration was revealed. [ABSTRACT FROM AUTHOR]