Arrhenius parameters for the reaction of the nitrate radical with 1,1-dichloroethene and (E)-1,2-dichloroethene

Abstract

The kinetics of the reactions of the nitrate radical, NO₃, with 1,1-dichloroethene and (E)-1,2-dichloroethene have been measured using the discharge-flow technique coupled to detection of NO₃ by optical absorption. The values obtained for the rate coefficients at room temperature are (1.2 ± 0.3)× 10^–15 and (1.2 ± 0.5)× 10^–16 cm³ molecule^–1 s^–1(95% confidence with 15% systematic errors included) and the derived Arrhenius expressions are k₂(T)=(4.7 ± 2.4)× 10^–13 exp[–(1800 ± 240)/T] and k₃(T)=(4.5 ± 0.5)× 10^–13 exp [–(2400 ± 40)/T] cm³ molecule^–1 s^–1(errors quoted at 1σ). Comparison of the results with those of previous studies indicates that Cl-atom elimination is not important for either reaction. The dependence of the kinetic parameters on the molecular structure of the dichloroethenes is discussed.