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In this work the thermochemistry of solution, solvation and hydrogen bond formation of chloroform in linear and cyclic ethers was studied. The infinite dilution solution enthalpies of chloroform in diethyl ether, diglyme, 1,4-dioxane, tetrahydrofuran, 12-crown-4 and 15-crown-5 were measured at 298.15 K. The solvation and hydrogen bonding enthalpies of chloroform in the ethers were calculated. It was found that the hydrogen bonding enthalpies of chloroform in the ethers are significantly higher for linear than for cyclic ethers. The hydrogen bonding of ethers with chloroform was discussed in cases when ethers act as a solute or solvent.

This work is devoted to the study of azeotropes by the method of solvation thermodynamics. In the present work the thermochemistry of alkane solutions in binary mixtures was studied. The infinite dilution solution enthalpies of n-hexane, n-octane, and n-dodecane in binary mixtures were measured at 298.15 K. Alkanes were used as solutes since they are not capable of specific interactions with solvents. It should be noted that the differences in the solution of alkanes in a series of solvents are caused by differences in the interactions between the solvent molecules. Binary mixtures (benzene–cyclohexane) and (n-hexane–acetone) at different molar ratios, including the compositions corresponding to azeotropes, were used. The composition of both azeotropes obtained by distillation was determined by means of densimetry, and was found to be in good agreement with published data. The compositions of chosen azeotropes insignificantly change with temperature. The excess solution enthalpies of n-alkanes in binary solvents were calculated. It was found that the extremum value of the excess solution enthalpy corresponds to their azeotrope composition.

Thermochemical studies of ionic liquids (ILs) in aqueous solution were carried out using solution calorimetry. Heat effects of dissolution in water at 298.15 K and molar limiting enthalpies of solution were measured for ILs having a common cation, 1-ethyl-3-methyl-imidazolium, connected with different anions: diethylphosphate, ethylsulfate, tetracyanoborate, thiocyanate, and trifluoroacetate. Molar enthalpies of solvation of ILs in water were derived from experimental data for solution and vaporization enthalpies. Enthalpic data were correlated with ionic liquid specific parameters and descriptors. The best correlation was observed with hydrogen-bonding interaction energies. This result confirmed that hydrogen bonding is one of the main types of intermolecular interactions inherent for ILs in aqueous solutions.