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Excess molar enthalpies, , of binary liquid mixtures containing as component 1 ethylene glycol, propylene glycol, di(ethylene glycol), tri(ethylene glycol), tetra(ethylene glycol), or some PEGs, such as PEG200, PEG300, PEG400, PEG600, and 2-phenylethyl alcohol (2), have been measured over the entire range of mole fraction x1 at 308.15 K and at atmospheric pressure, using a flow microcalorimeter. The values of vary from a value of −600 J·mol-1 (mixture containing PEG600) up to a maximum of 254 J·mol-1 (mixture containing propylene glycol) decreasing as the chain length of glycols or PEGs increase. Curves are not symmetric, and in the case of mixtures containing PEGs, an intersection among the curves at x1 ≈ 0.65 has been observed. Results were fitted to the Redlich−Kister polynomial to estimate the adjustable parameters and the standard deviations between experimental and calculated values. Qualitative discussion of H bonding in the liquid state is given.

Excess molar enthalpies, H m E , of binary mixtures containing phenetole (ethoxy benzene)+α-pinene, or β-pinene have been determined in the range (288.15–313.15) K, and at atmospheric pressure using a flow microcalorimeter. H m E curves are symmetrical with positive values over the entire concentration range and show higher values for the mixture containing α-pinene (the maximum value for H m E is 1072 J mol −1 ). Only a slight influence of temperature on excess molar enthalpies has been observed for both systems. Experimental results have been correlated using the Redlich–Kister polynomial and the adjustable parameters have been evaluated by least-squares analysis. Results have also been interpreted by an extended modified cell model of Prigogine.

Excess molar enthalpies, H m E , of binary mixtures containing propylene carbonate + six n -alkoxyethanols have been determined using an LKB flow microcalorimeter at 288.15, 298.15, and 313.15 K and at atmospheric pressure. The alkoxyethanols were 2-methoxyethanol, 2-ethoxyethanol, 2-butoxyethanol, 2-(2-methoxyethoxy)ethanol, 2-(2-ethoxyethoxy)ethanol, and 2-(2-butoxyethoxy)ethanol. From the experimental data, deviations in H m E have been determined and fitted to the Redlich–Kister polynomial to estimate the binary interactions parameters.

Excess molar enthalpies of binary mixtures containing diethyl carbonate + fourteen n -alkyl alkanoates (six acetates, four propanoates and four butyrates) have been determined at 298.15 K and at atmospheric pressure using an LKB flow microcalorimeter. The experimental data have been fitted to the Redlich-Kister equation to estimate the binary parameters. The results have been qualitatively discussed.