The Kinetics of the Fast Gas-Phase Reaction between Nitryl Chloride and Nitric Oxide

The kinetics of the fast reaction between nitryl chloride and nitric oxide has been studied by absorptiometric methods in two systems of greatly different surface‐to‐volume ratio and over a temperature range from 1° to 71°. The pressure of each reactant has been varied from 0.1 mm to 18 mm and the total pressure from 0.2 mm to 384 mm. The reaction proceeds quantitatively according to the equation $${\mathrm{ClNO}}_2+\mathrm{NO}={\mathrm{NO}}_2+\mathrm{ClNO}.$$ It is homogeneous and first order with respect to each reactant. The second‐order rate constant is expressed by the equation $${\text{k=0.83×10}}^{12}\hspace{0.17em}\exp \text{(−6900/RT)}\mathrm{cc}\hspace{0.17em}{\mathrm{mole}}^{\text{−1}}\hspace{0.17em}{\sec }^{\text{−1}}.$$ An elementary bimolecular mechanism is proposed.