Monochloramine reacts with hydrated electrons very rapidly, k(NH_2Cl + e_(aq)~-) = (2.2 ± 0.3) * 10~(10) L mol~(-1) s~(-1), to produce ~·NH_2 radicals. It reacts with ~·OH radicals more slowly, k(NH_2Cl + ~·OH) = (5.2 ± 0.6) * 10~8 L mol~(-1) s~(-1), to produce ~·NHCl radicals. While ~·NH_2 exhibits an absorption peak at 530nm, with a molar absorption coefficient ε_(530) = 80 L mol~(-1) cm~(-1), ~·NHCl exhibits two peaks at 330 and 580 mm, ε_(530) = (85 ± 30) L mol~(-1) cm~(-1) and ε_(580) = (56 ± 30) L mol~(-1) cm~(-1). The ~·NHCl radical undergoes self-decay and can react also with O_2 to form a peroxyl radical. It is suggested that the peroxyl radical exists in equilibrium NHClO_(2~·) <=> ~·NHCl + O_2 with an estimated equilibrium constant of (3 ± 2) * 10~(-3) mol L~(-1). The reaction of chloramine with the carbonate radical is suggested to form a complex [CO_3NH_2Cl]~(·-) with k_f = 2.5 * 10~5 L mol~(-1) s~(-1) and k_r = 4 * 10~2 s~(-1), and this complex decomposes with k = 7 * 10~2 s~(-1) to form ~·NHCl.
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