The freezing points, enthalpies of dilution, volumetric heat capacities, densities, and sound velocities of the homologous series R(CH3)2NO, for R = butyl, hexyl, octyl, and decyl, were measured in water at 25 °C and as a function of temperature in the case of octyl. The osmotic coefficients and the apparent and partial molar relative enthalpies, heat capacities, volumes, compressibilities, and expansibilities were calculated. Isochoric heat capacities and isothermal compressibilities can also be derived from these data. There is a gradual change in the trends of these functions when going from the lower homologue, which behaves like a medium-size alcohol, to the higher one, which is a typical nonionic surfactant. The osmotic coefficients are positive in the premicellar region at the freezing temperature but become negative at higher temperatures. The concentration dependence of the various functions can be accounted for quantitatively with a simple mass-action model. Aggregation numbers and thermodynamic functions of micellization can be derived with this model.

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Excess molar volumes and isobaric excess molar heat capacities for 1,4-dioxane + 1-butanol, 1-pentanol, 1-hexanol, 1-heptanol, 1-octanol, 1-nonanol, and 1-decanol and excess molar enthalpies for the binary mixtures 1,4-dioxane + methanol, 1-propanol, 1-butanol, 1-pentanol, 1-hexanol, 1-heptanol, 1-octanol, 1-nonanol, and 1-decanol at the temperature 298.15 K have been determined as a function of mole fraction. The magnitude of these experimental quantities is discussed in terms of the nature and type of intermolecular interactions in binary mixtures. When available, the results have been compared with literature values.

Excess molar volumes for {1,4-dioxane + heptane, octane, nonane, and decane} at the temperatures 288.15 K, 298.15 K, and 308.15 K, excess molar enthalpies for {1,4-dioxane + heptane, octane, nonane, decane, dodecane, tetradecane, and hexadecane} at the temperature 298.15 K, and isobaric excess molar heat capacities for {1,4-dioxane + heptane, octane, nonane, and decane} at the temperature 298.15 K have been determined as a function of mole fraction. The magnitude of these experimental quantities is discussed in terms of the nature and type of intermolecular interactions in binary mixtures.