OH OH H₂O₂ (hydrogen  peroxide) OH H H₂O H H H₂ H₂O H e_aq H₂ OH H₂ OH H₂O H 2H₂O₂ O₂ 2H₂O 4 (  H₂O radiation e H₂O ) 4 (  H₂O H₂O H₃O OH  ) e_aq H₃O H H₂O 2(  OH OH H₂O₂  ) Reactor Water Chemistry DOE-HDBK-1015/2-93 EFFECTS OF RADIATION ON WATER CHEMISTRY (SYNTHESIS) Rev. 0 CH-03 Page 3 Because Reactions (3-4) and (3-5) are slow compared to that in Reaction (3-3), there are three reactive species present at any one time:  hydroxyl radicals (OH), hydrated electrons (e    ), and aq - hydrogen atoms (H).  These species may undergo any of several possible reactions such as the following. (3-6) (3-7) (3-8) (3-9) (3-10) Hydrogen peroxide, formed by Reaction (3-6), may also react with the original reactive species, but at high temperatures H  O   is unstable, and the predominant reaction is decomposition. 2 2 (3-11) To illustrate the overall result of these reactions, let us assume that each of the reactive species produced  by  successive  steps  in  the  irradiation  of  water  reacts  in  only  one  way.    That  is, whenever several reactions of a particular substance are possible, assume that one predominates to such an extent that the others are negligible.  The following set of reactions is one possibility. In some cases, entire reactions are multiplied by a factor to allow cancellation of terms when the reactions are summed. (3-1) (3-3) (3-4) (3-6)