A LASER FLASH-PHOTOLYSIS STUDY OF THE DECAY OF CL-ATOMS AND CL-2(-) RADICAL-ANIONS IN AQUEOUS-SOLUTION AT 298 K

The rate coefficient for the reaction of Cl atoms with (1) H2O and of Cl-2(-) radical anions with (2) H2O and (3) OH- have been determined u sing laser photolysis for the generation of Cl/Cl-2(-) and long path l aser absorption for the time resolved detection of Cl-2(-). The follow ing results were obtained: k(1) = (2.3 +/- 0.6).10(5) s(-1), k(2)<610 s(-1) and k(3) = (4.0+/-0.6).10(6) M-1 s(-1). It is concluded that the lifetime of Cl/Cl-2(-) in aqueous solution strongly depends on the Cl - content and on pH.