Densities and speeds of sound for LiCl in 1-butyl-3-methylimidazolium tetrafluoroborate (bmimBF(4)) and in water were accurately measured as a function of concentration at five temperatures from 288.15 K to 308.15 K. Apparent molar volumes and isentropic compressions were calculated from the measured density and speed of sound data. Infinite dilution values of these derived thermodynamic properties were obtained by a suitable extrapolation procedure. The temperature dependence of apparent molar volumes at infinite dilution was also examined. The results were discussed in terms of interactions between LiCl and bmimBF4 in comparison with those between LiCI and water. (C) 2017 Elsevier Ltd.