Rate of solution of gaseous sulphur dioxide at atmospheric concentrations

Liss¹ has calculated the rate of exchange between sulphurdioxide and environmental water. We report here experimental work which verifies the results of his calculations. The rate of solution of SO₂ at 20° C was examined by passing a nonlaminar flow of air (bulk velocity ∼1.5 cm s^-1) and ³⁵SO₂ at concentrations around 300 μg m^-3 over stirred sodium perchlorate solutions. The pH values of these solutions were adjusted by addition of sodium hydroxide or perchloric acid because ionic strength exerts little effect on rate of uptake. Oxidation of the sulphur (IV) anions in sodium perchlorate solution is small over the time scale involved (unpublished data of P. B.). © 1972 Nature Publishing Group.