Laboratory studies of the reactions of the nitrate radical with chloroform, methanol, hydrogen chloride and hydrogen bromide

Abstract

Arrhenius parameters have been measured over the temperature range 298–523 K for the hydrogen abstraction reactions of NO₃ with CH₃OH, CHCl₃ and HCl. A rate constant was determined at room temperature for the reaction of NO₃ with HBr. Kinetic data were obtained by the discharge-flow technique operating at total pressures between 1.8 and 5.2 mmHg. The rate expressions derived for the interactions with CH₃OH, CHCl₃ and HCl are 1.2 × 10^–12 exp (–2560/T), 8.6 × 10^–13 exp(–2815/T), and 4.0 × 10^–12 exp(–3330/T)cm³ molecule^–1. For the reaction of NO₃ with HBr, the rate constant is 1.3 × 10^–16 cm³ molecule^–1s^–1 at 298 K. The hydrogen-abstraction reactions of NO₃ are compared with those of O(³P) and OH.