Kinetics of the reaction OH plus CO under atmospheric conditions

The rate coefficients for the reaction of OH with CO, k(1) at pressures of 50 - 750 Torr from 220 K to 400 K, in He, N-2, and air, are reported to be k(1) = (1.57 x 10(-13) + 3.54 x 10(.33) x [M]) cm(3) molecule(-1) s(-1), wi th [M] in molecule cm(-3), k(1) increases linearly with the bath gas number density; this increase is independent of temperature. k(1), at a given tem perature and number density, is the same in N-2, dry air, and mixtures of O -2 (up to 49%) and N-2. The presence of water vapor does not significantly alter k(1) under atmospheric conditions. The uncertainty in our value of k( 1) is +/- 15%, at the 95% confidence level, at any given [M] and temperatur e, which is smaller than the currently recommended uncertainty by a factor of four or more. Our k(1) values are compared with previous data and their atmospheric implications are discussed.