The solubilities of sodium chloride, sodium bromide, and potassium bromide in the solvents water, methanol, ethanol, and methanol + ethanol as well as those of sodium bromide in water + methanol and sodium bromide and potassium chloride in water + ethanol mixed solvents were measured in the range between 298.15 and 348.15 K using an analytical gravimetric method. When possible, the reliability of the method was checked by comparing the experimental data with literature values. The method proved to be very accurate, and the solubilities are generally reproducible when compared to the data reported in the literature.

Density, speed of sound, refractive index, and viscosity of the commercial ionic liquids 1-ethyl-3-methylpyridinium bis(trifluoromethylsulfonyl, and 1-hexyl-3-methylimidazolium dicyanamide, [HMim][N(CN) 2 ] were measured as a function of temperature at atmospheric pressure. The density, speed of sound, and refractive index data were properly fitted to a linear equation, while viscosity data were fitted to Arrheniuslike law, Vogel−Fulcher−Tamman (VFT), a modified VFT, Litovitz, and fluidity equations. Besides, from the experimental density values, the thermal expansion coefficient, α, was calculated. Moreover, the experimental data were used to analyze the effect of temperature, the role of the alky chain length of the cation, and the influence of the nature of the ions (cation and anion) on the physical properties. Finally, an exhaustive comparison with available literature data of the studied ionic liquids was also carried out.

In this work, the aqueous solubilities of two hydroxybenzoic acids (gallic and salicylic acid) and three phenylpropenoic acids (trans-cinnamic, ferulic, and caffeic acids) are addressed. Measurements were performed, as a function of temperature, between 288.15 and 323.15 K, using the shake-flask method for generating the saturated aqueous solutions, followed by compositional analysis by spectrophotometric and gravimetric methods.The pH values of the saturated aqueous solutions were measured by potentiometry. Additional thermodynamic properties, which are fundamental for a better understanding of the solubilization process, as well as necessary for the modeling studies, such as melting temperatures and fusion enthalpies were determined by differential scanning calorimetry (DSC). Apparent acid dissociation constants (K a ) were obtained by potentiometry titration. The measured data were modeled with the cubic-plus-association (CPA) equation of state (EoS). This EoS is applied, for the first time, for multifunctional associating molecules, and the results indicate that it can adequately be used to represent the measured and other literature data with satisfactory accuracy.

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