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Densities and speeds of sound were measured for binary mixtures of butan-2-one with methanol, propan-1-ol, butan-1-ol, and chloroform at temperatures of 293.15–323.15 K and at atmospheric pressure, with the uncertainties of 0.05 kg·m–3 and 0.5 m·s–1, respectively. The molar excesses of volume, isentropic compression, and thermal expansion were calculated for those systems from the measured speeds and densities and for the mixture of butan-2-one with ethanol from the data reported in the literature. The negative excess volumes for the mixtures with alcohols decrease with the elongation of the hydrocarbon chain, and they eventually become positive for propan-1-ol and butan-1-ol at higher temperatures. That probably reflects the vanishing difference in size of the molecules in the mixture. The excess volume of butan-2-one + chloroform is close to that of butan-2-one + methanol. The excess expansion of butan-2-one + chloroform is negative, and it is positive for butan-2-one + alcohols, while the excess compression isotherms are approximately mirror images of those of the excess expansion. That results probably from the counteracting effects of temperature and pressure on the aggregation due to hydrogen bonds.

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The enthalpies of formation of 2-, 3-, and 4-CH3-benzamide, as well as for 2-CH3O-benzamide were measured by using combustion calorimetry. Vapor pressures of the isomeric CH3- and CH3O-benzamides were measured by using the transpiration method. The enthalpies of sublimation/vaporization of these compounds at 298 K were obtained from temperature dependencies of vapor pressures. The enthalpies of solution of the isomeric CH3- and CH3O-benzamides were measured with solution calorimetry. The enthalpies of sublimation of m- and p-substituted benzamides were independently derived with help of a solution calorimetry based procedure. The enthalpies of fusion of the CH3-benzamides were derived from DSC measurements. Thermochemical data on CH3- and CH3O-benzamides were collected, evaluated, and tested for internal consistency. A simple incremental procedure has been suggested for a quick appraisal of vaporization enthalpies of substituted benzamides. The high-level G4 quantum-chemical method was used for mutual validation of the experimental and theoretical gas phase enthalpies of formation. A remarkable ability of the G4 based atomization procedure to calculate reliable enthalpies of formation has been established for the set of aliphatic and aromatic amides. An outlook for the proper validation of the G4-AT procedure was discussed.