Water effect on physicochemical properties of 1-butyl-3-methylimidazolium based ionic liquids with inorganic anions

► Physicochemical properties of 1-butyl-3-methylimidazolium ionic liquids were determined. ► The conductivity of equimolar [bmim][BF4] water solution exhibited the local maximum. ► Crystalline hydrates of [bmim][BF4] × 0.5H2O composition were observed.