Ionic liquids are molten salts that have a unique set of physical and chemical properties. Their characteristic properties include; non-flammability, high thermal and chemical stability, wide liquid range and negligible vapor pressure. Ionic liquids as green solvents can be used in separation processes, electrochemistry, metal extraction and organic synthesis [1-3]. In a comparative study, the thermodynamic properties of ionic liquids, including density, sound velocity and surface tension by experimental data and molecular dynamics simulation are investigated. Also, to study the vapor−liquid equilibria behavior, the isopiestic equilibrium measurements are carried out for the ternary ionic liquid 1 + ionic liquid 2 + H2O.
