Evaluation of molecular interactions by volumetric and acoustic studies in binary mixtures of the ionic liquid [EMIM][MeSO4] with ethanoic and propanoic acid at different temperatures

In the present work, molecular interactions in the binary mixtures of 1-Ethyl-3-methylimidazolium methylsulphate IEMIMI[MeSO4] with ethanoic acid (EA) and propanoic acid (PA) have been evaluated using the measured densities (rho) and speeds of sound (u) over the entire range of composition at temperatures of 298.15, 303.15, 308.15 and 313.15 K. The excess volumes (V-E) for the said binary mixtures have been computed from the experimental density data. Further, excess isentropic compressibilities (K-S(E)) have been calculated from density and speed of sound data for the binary mixtures. The V-E and K-S(E) values for the binary mixtures were found to be negative over the whole range of composition at all the specified temperatures which suggest the existence of specific interactions between component molecules. Furthermore, Redlich-Kister equation was used to fit the derived excess functions V-E and K-S(E) in order to determine the fitting parameters and the root mean square deviations. (C) 2016 Elsevier B.V. All rights reserved.