Application of the Baheʹs pseudolattice-theory to water—1-butyl-3-methylimidazolium tetrafluoroborate (bmimBF4) mixtures at 298.15 K: Part I. Autoprotolysis constants

The autoprotolysis constants (Ks) of water – 1-butyl-3-methylimidazolium tetrafluoroborate (bmimBF4) mixtures were determined at 298 K over the composition range of 0 to 77.43 vol.% bmimBF4 using potentiometric method with a glass electrode. A slight increase in the autoprotolysis constant was observed when the salt was added to the water. The value of the ionic product of the medium then decreases as the bmimBF4 content increases from about 20 vol.%. The acid–base properties of these media were perfectly described by Baheʹs approaches that were completed by Varela et al. concerning structured electrolyte solutions with large short-range interactions.