J. Phys. Chem. 1989, 93, 7435-7440 The micellar effects on the dehydrobromination reaction of that para-substituted 2-phenylethyl bromides give values of are relatively insensitive to the reaction conditions or to changes in nature of para substituents of the benzene ring of the organic and K$' values can be related to the reagents. The G:,, expected sequence, i.e., NO3- > Br- > C1-, as they follow the strengths of binding of the investigated anions to the given micelle. Le., 38, 32, and 9 for X = NO3-, Br-, The high values of and Cl-, respectively, mean that both organic reagents, 2-(pnitropheny1)ethyl and 2-phenylethyl bromides, significantly affect the binding of OH- and X- ions to CTAX micelles. In the literature there are significant differences between the values adopted by various groups for the ion-exchange p a r a m e t e r ~ . ~ ~Com~'-~~ petition experiments of the binding of arenesulfonate ions to CTAX micelles gave = 23, 21, and 4.1 for X = NO