A Laser Photolysis Study of the Reaction of SO4- with Cl- and the Subsequent Decay of Cl2- in Aqueous Solution

Article abstract of DOI:10.1021/j100369a044

Kinetic spectroscopic techniques were employed to investigate the reactions of the SO4- and Cl2- radicals following photolysis of K2S2O8-NaCl solutions at 248 nm.The extinction coefficient of SO4- was estimated to have a value of (1.6 +/- 0.1) * 1E3 M^-1 cm^-1 (base 10) at 450 nm, its wavelength of maximum absorbance.A mechanism is proposed which accounts for the observed decay of Cl2- in aqueous solution.Several rate coefficients have been determined at 20 deg C: k(SO4- + Cl-) = (2.7 +/- 0.4) * 1E8 M^-1 s^-1 (at zero ionic strength), 2k(Cl2- + Cl2-) = (1.4 +/- 0.2) * 1E9 M^-1 s^-1 (at zero ionic strength), k(Cl2- + H2O) = (1.3 +/- 0.1) * 1E3 s^-1, and k(Cl * H2O) = (2.5 +/- 0.2) * 1E5 s^-1.