HR: 09:00h
AN: A41B-04    [PDF]
TI: Direct Observation of the Kinetics of an Atmospherically Important Reaction at the Air-Aqueous Interface
AU: * Mmereki, B
EM: bmmereki@chem.utoronto.ca
AF: Department of Chemistry University of Toronto, 80 St. George St., Toronto, Ont M5S 3H6 Canada
AU: Donaldson, D
EM: jdonalds@chem.utoronto.ca
AF: Department of Chemistry University of Toronto, 80 St. George St., Toronto, Ont M5S 3H6 Canada
AB: Many atmospherically important chemical processes are believed to occur at the interface between the air and aqueous phases. We report direct measurements of the kinetics of a reaction between gas phase ozone and anthracene adsorbed at the air-aqueous interface by monitoring the laser-induced fluorescence of the adsorbed anthracene. The reactions at the "clean" air-water interface and at an interface consisting of one monolayer of 1-octanol were studied. For both cases, the reaction follows a Langmuir-Hinshelwood mechanism, in which ozone first adsorbs to the air-aqueous interface, and then reacts with adsorbed anthracene. The estimated reactive uptake coefficient at the clean air-water interface is about 6 x 10-8 for typical atmospheric ozone concentrations; this value increases by about a factor of 5 when the water surface is coated with a monolayer of 1-octanol.
DE: 0305 Aerosols and particles (0345, 4801)
DE: 0317 Chemical kinetic and photochemical properties
DE: 0345 Pollution--urban and regional (0305)
SC: Atmospheric Sciences [A]
MN: 2003 Fall Meeting