Volumetric properties of aqueous solution of [C3mim][Ac] and [C4mim][Ac] from 283.15 to 323.15Â K

The densities of 1-alkyl-3-methylimidazolium acetate [C3mim][Ac] and [C4mim][Ac] aqueous solution were measured in the concentration from 0.05000 to 3.000 mol·kg− 1 over the temperatures range from 283.15 to 323.15 K. The coefficient of thermal expansion of the solution, α, apparent molar volume, ϕVB, the apparent molar expansibility of the solute, ϕE and the partial molar volume were calculated. The Pitzer's model was used to establish an equation to describe the volumetric properties and the corresponding parameters βMX(0)V, βMX(1)Vand CMXV were obtained. Comparing the values of VB0obtained by Pitzer's method with those values of Vϕ0calculated by Redlich and Meyer's shows that Pitzer's formulism can be applied in the aqueous solution of ionic liquids.