Densities of the aqueous solutions of ionic liquid 1-butyl-3 metilmidazolium chloride [Bmim + ][Cl - ] were determined using a vibrating tube densitometer Anton Paar DMA 5000 at a temperature range between (283.15 - 218.15) K. The apparent molar volumes V f of aqueous chloride1-butyl-3-methylimidazolium were calculated and adjusted to the Pitzer ion interaction model, obtaining the limiting apparent molar volumes V f and Pitzer volumetric parameters b (O) M V X , b (1) M V X , C V MX at temperatures of 283.15, 288.15, 293.15, 298.15, 303.15, 313.15 and 318.15K, proving that this model adequately represents the experimental volumetric data below an ionic strength of 0.6018 mol / kg. Finally the limiting apparent molar expansibilities f O E were calculated from the limiting apparent molar volumes at various temperatures and the results are discussed in terms of the interactions occurring in solution.