Thermodynamic properties of aqueous solutions of two ammonium-based protic ionic liquids at 298.15Â K

► Thermodynamic properties of ethylammonium acetate + water and propylammonium acetate + water systems were reported at 298.15 K. ► The interactions and structural effects were analyzed based on the volumetric, refractive index and conductivity properties. ► Redlich-Kister equation was used to correlate the excess molar volumes and refractive index deviations. ► The concentration dependence of electrical conductivity was fitted according to the empirical Casteel-Amis equation.