The surface tension of aqueous solutions of methanol, ethanol, 1-propanol, and 2-propanol was measured over the entire concentration range at temperatures of 20-50 °C. The experimental values were correlated with temperature and with mole fraction. The maximum deviation was in both cases always less than 3%.

The surface tension of aqueous solutions of monoethanolamine, 2-amino-2-methyl-1-propanol, and monoethanolamine + 2-amino-2-methyl-1-propanol was measured at temperatures from 25 °C to 50 °C. The concentration ranges were 0−100 mass % monoethanolamine and 2-amino-2-methyl-1-propanol, and for tertiary mixtures 50 mass % total amine concentration (the concentration range for each amine was 0−50 mass %). The experimental values were correlated with temperature and mole fraction. The maximum deviation was in both cases always less than 0.5%.

The surface tensions of aqueous solutions of formic acid, acetic acid, and propionic acid were measured over the entire concentration range at temperatures (20 to 50) °C. The experimental values were correlated with temperature and mole fraction. Maximum deviations were in both cases always less than 1%.

This report describes the synthesis of ionic liquids that incorporate the N-methyl-2-hydroxyethylammonium cation with various carboxylic acid anions and the study of some of their physical properties, including self-diffusion coefficients, density, speed of sound, viscosity, and refractive index. 1 H and 13 C NMR spectra were used to characterize the chemical structure of the species in concordance with FT-IR spectra. DOSY NMR spectra was used to determine the self-diffusion coefficients of the components, which were consistent with the formation of a lamellar or micellar liquid-crystal phase in samples containing an alkyl chain in the anion species. Thermoacoustic parameters showed that anion alkyl chain has an influence on the molecular packing of these ionic liquids. In addition, the effect of temperature on the properties seems to be related to the size and the type of aliphatic chain of the ionic liquid.