Reaction of Carbon Dioxide with Atomic Oxygen and the Dissociation of Carbon Dioxide in Shock Waves

The reaction of oxygen atoms with carbon dioxide has been investigated from 2800–3200°K using the decomposition of N₂O as a source of oxygen atoms: O+CO₂→CO+O₂ (1). Over the temperature range, the value of $k_1$ was found to be $\log k_1\text{\hspace{0.17em}=\hspace{0.17em}−\hspace{0.17em}10.59(±\hspace{0.17em}0.79)\hspace{0.17em}−\hspace{0.17em}(32 500\hspace{0.17em}±\hspace{0.17em}10 900)\hspace{0.17em}/\hspace{0.17em}4.58 T}{\mathrm{cm}}^3/\mathrm{particle\; sec}$ , which is much larger than the recent literature value. The addition of molecular oxygen decreased the observed rate of CO₂ removal in Reaction (1). The decomposition of CO₂ in the second‐order pressure region in neon diluent was investigated over the temperature range 2900–4000°K, and it was shown that the contribution of Reaction (1) to the gross decomposition rate is significant, but does not account for the anomalously low activation energy of CO₂ decomposition. The corrected first‐order rate constant for the reaction CO₂+Ne→CO+O+Ne (2) at a density of 1.35 × 10¹⁸particle/cm³, is $\log k_2\text{\hspace{0.17em}=\hspace{0.17em}7.71 (±\hspace{0.17em}0.36)\hspace{0.17em}−\hspace{0.17em}(74 100\hspace{0.17em}±\hspace{0.17em}6300)\hspace{0.17em}/\hspace{0.17em}4.58T}{\sec }^{\text{−1}}$ . The rate constant for the reaction O₃+NO→N+O₂ (3) is estimated as $k_3{\text{\hspace{0.17em}=\hspace{0.17em}1.5\hspace{0.17em}×\hspace{0.17em}10}}^{\text{−14}}{\mathrm{cm}}^3/\mathrm{particle}·\sec$ at 3000°K, and a suggested upper limit for the rate constant of the reaction NO+CO₂→NO₂+CO (6), is $k_6{\text{\hspace{0.17em}≤\hspace{0.17em}5\hspace{0.17em}×\hspace{0.17em}10}}^{\text{−15}}{\mathrm{cm}}^3/\mathrm{particle}·\sec$ at the same temperature.