Kinetics of the hydrolysis of the dichromate ion. III. Environmental effects on rate constants and activation energies

Kinetic Salt Effects and Structure of the Aqueous Solution

“…Only Scatchard [56] in 1953 used a new theory of solutions, developed by Mayer [43] to try and give an interpretation of the main effect observed by Olson and Simonson, that is: in a reaction between two ions of the same sign, the salt effects are not determined by the ionic strength but by the nature and concentration of the ions of sign opposite to that of the reactants. This "Olson-Simonson effect" has been confirmed by all workers at all concentrations with very few exceptions [3,11,15,39,42,48,50,54,55,57,59]. In some cases the increase in ionic strength caused by the increase in charge of ions of the same sign as that of the reactants produces a decrease in rate, contrary to the expectation of the Br¢nsted-Debye theory.…”

The Temperature‐Dependence of E a

“…D) but is already apparent in reactions amenable, for instance, to measurement in the T-jump or stopped flow apparatus (95,127). Nevertheless, when they have nonzero values of dEa/dT there is a good chance of detecting the fact: when Ea itself is low, its relative change with temperature may be quite appreciable and easily detected.…”

Energy of Activation and Water Structure

“…We should here like to make the tentative suggestion that, in hydrolysis reactions, the two -or morepossible forms of the reactant should be different fo:rnJS of water. We have recently applied this suggestion to a specific example, namely the hydrolysis of dichromate [20].…”