Absolute Values of the Velocity Constants in the Formation of Semiquinone

Abstract

A mechanism for the autoxidation of hydroquinone and its homologs was presented in a previous paper. From this mechanism it is now possible to calculate a lower limit for the absolute velocity constant of the formation of semiquinone ions from quinone and doubly charged hydroquinone ions, and an estimate of this constant can be given in the analogous case of Ψ‐cumohydroquinone. In both cases, the velocity constant is found to be remarkably high; under special experimental conditions the velocity of this reaction should become of the same order of magnitude as the velocity of the recombination of the doubly charged hydroquinone ions with hydrogen ions, thus providing a test for this latter velocity.