Effects of on the Reaction Rates

In the very early phase of the kinetic studies on the effects of [micelles] on the reaction rates, it has been observed that an empirical kinetic equation similar to Equation 7.48 with replacement of [M X ] by [Smflj - CMC (where [Smflj and CMC represent total surfactant concentration and critical micelle concentration, respectively) is applicable in many micellar-mediated reactions. But the plots of kobs vs. ([Surf]j - CMC) for alkaline hydrolysis of some esters reveal maxima when surfactants are cationic in nature. - - Similar kinetic plots have also been observed in the hydrolysis of methyl orthobenzoate in the presence of anionic micelles. Bunton and Robinson suggested a semiempirical equation similar to Equation 7.49, which could explain the presence of maxima in the plots of ko s vs. ([Surflj - CMC). In Equation 7.49), J, is an empirical constant. 

2 Effects of [Inert Salts] on l oi,s for Ionic Micellar-Mediated Semiionic Reactions 

The effects of inert inorganic and organic salts on k bs for alkaline hydrolysis of phenyl benzoate and phthalimide, as evident from observed data for two typical sets of observations shown in Table 7.10 and Table 7.11, have been explained in terms of the semiempirical kinetic equation Equation 7.50, which 

Pseudo-First-Order Rate Constants (koi,s) for Hydrolysis of Phenyl Benzoate at Different [NaCI] in the Presence of 0.01-M NaOH and 0.007-M CTABr 

Note Reaction condition [Phenyl benzoate], = 2 x 1(H M, 35°C, the aqueous reaction mixture in each kinetic run contains 2% v/v CH3CN and CTABr represents cetyltrimethylammonium bromide. 

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