| Abstract
| - Specific ionic effects on numerous solid−aqueous solution interfaces have usually been ranked in the so-called Hofmeister series. Ion specificity has experimentally been manifested in many ways. In this work, thecolloidal stability and electrophoretic mobility of three different polystyrene latex samples are analyzed inthe presence of different electrolytes. The effects on their colloidal stability and electrokinetic behavior provokedby four anions (SO42-, Cl-, NO3-, and SCN-) and three cations (NH4+, Na+, and Ca2+) located in differentpositions in the Hofmeister series are shown. Some of these ions specifically modified the pair potentialinteraction of the colloidal particles yielding results not explained by the Derjaguin, Landau, Verwey, andOverbeek (DLVO) theory. A modification in the repulsive electrostatic term of this theory is then proposedto consider the ionic specificity. In addition, general but qualitative explanations about the subjacent mechanismsinvolved in the Hofmeister effects are also summarized.
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