The experimental density, d, values as function of ionic liquid concentration, m, for binary mixtures, [MMIm]MSO4 + methanol, + water, + DMSO,+ DMF, and + MeCN at T = (298.15-328.15) K are reported. Apparent molar volumes V-phi have been determined from the experimental densities and fitted to a Redlich-Mayer equation for the calculation of limiting apparent molar volume values V-phi(0). The values of V-phi(0) have the following order in the investigated systems: MeCN < MeOH < DMF < DMSO < H2O. The calculated V-phi(0) values indicate that ionic liquid + molecular solvent interactions in water and DMSO are stronger than the other solvents. The limiting apparent molar expansibilities E-phi(0) show that at each temperature E-phi(0) values for ionic liquid in H2O and DMSO have positive values and decrease with rising temperature. The calculated values of (partial derivative V-2(phi)0/partial derivative T-2)(P) for binary mixtures of containing [MMIm]MSO4 have small and negative values for studied systems. Therefore, ionic liquid under study is predominantly a structure breaker. (C) 2010 Elsevier B.V. All rights reserved.