Thermodynamic Properties of a Series of Closely Related Ionic Liquids Based on 1-Alkyl-3-methylimidazolium Hydrosulfate

The densities of a series of ionic liquids [ C-4 mim ] HSO4 ( 1-butyl-3-methylimdazolium hydrosulfate ), [ C-6 mim ] HSO4 ( 1-hexyl-3-methylimdazolium hydrosulfate ), [ C-8 mim ] HSO4 ( 1-octyl-3-methylimdazolium hydrosulfate ) and [ C-10 mim ] HSO4 ( 1-decyl-3-methylimdazolium hydrosulfate ) were determined from 293. 15 K to 343. 15 K. The coefficients of thermal expansion and molecular volume of the ionic liquids were calculated from the density results. Standard entropies and lattice energy of the ionic liquids were calculated from the experimental density values using Glasser's equation. The thermodynamic properties of the ionic liquid were further discussed.