Reactant-solute encounters in aqueous solutions studied by kinetic methods: hydration cosphere overlap and camouflage effects

Rates of chemical reactions in aqueous solutions are often sensitive to low concentrations of added solutes such as ureas, alcohols, alpha-amino acids and carbohydrates. In this work, several simple chemical reactions were us ed to probe this sensitivity, which arises from interactions between added solute and the reacting solute. It was found that derived interaction param eters provide a novel insight into interactions between solute molecules in aqueous solution. For example, it was possible to identify two interesting effects, which are termed (i) 'destructive overlap' of hydration cospheres and (ii) 'camouflage effects' by water-solute interactions. (C) 1998 John Wiley & Sons, Ltd.