THE REDUCING RADICALS PRODUCED IN WATER RADIOLYSIS: SOLUTIONS OF OXYGEN—HYDROGEN PEROXIDE—HYDROGEN ION1

Abstract

The reducing radical H or H2O- arising from the gamma radiolysis of water is shown to react competitively with dissolved O2 and H2O2; the ratio of the respective rate constants is 2.0. lt also reacts in a simple competitive bimolecular fashion with hydrogen ion, H+, to give an acid form of the radical which reacts several thousand ttmes as fast with O2 as with H2O2. The rate constants for reaction of H with O2 and with H+ are equal. The yield of H deduced from the O2-H2O2 competition in neutral solution is 2.85, which is equal to the standard value of the total yield of reducing radicals. Thus essentially none of the reducing radicals appear to be generated initially in the acid form, a conclusion which disagrees with recently proposed interpretations of some other radiolytic reactions.