Kinetics of Reaction between Hydrogen and Nitrogen Dioxide

The gas‐phase reaction between hydrogen and nitrogen dioxide has been studied in the temperature range from 600 to 700°K. The stoichiometry of the reaction corresponds closely to $${\mathrm{H}}_2+{\mathrm{NO}}_2=\mathrm{NO}+{\mathrm{H}}_2\mathrm{O}.$$ The rate of disappearance of NO₂ is given by $$\frac{\mathrm{-d(}{\mathrm{NO}}_2)}{\mathrm{dt}}=\frac{{10}^{14}({\mathrm{NO}}_2\mathrm{)(}{\mathrm{H}}_2{)}^{\text{1.4}}{e}^{\text{−46\hspace{0.17em}000R/T}}}{({\mathrm{NO}}_2\mathrm{)+(}\mathrm{NO})}.$$ The experimental observations are interpreted in terms of a chain mechanism involving hydrogen atoms and hydroxyl radicals as chain carriers.