Further Studies on the Oxidation of Nitric Oxide; the Rate of the Reaction between Carbon Monoxide and Nitrogen Dioxide

Abstract

The initial rate of the reaction between CO and NO₂ from 225°C to 290°C was measured under conditions which precluded the possibility of NO₂ decomposition. This study extends the earlier data on the reaction over a 300° temperature interval. The oxidation of nitric oxide at 25°C and at pressures from 0.01 to 0.1 mm of NO was found to be third order over a 3‐ and 6‐fold change in reactants. The CO₂ and NO₂ production in systems containing NO, CO, and O₂ around 150°C was measured under conditions in which the formation of CO₂ by the reaction between CO and NO₂ was negligible. It is concluded that NO₃ is the intermediate needed to correlate this and previous data on reactions involving NO and NO₂, and that the rate of the reaction of NO₃ with NO is faster than that with CO. A new apparatus containing greaseless valves capable of handling quantities of products of the order of 10^—3 mm, and a method of analysis precise to 3×10^—5 mm was devised. Methods to prepare reactant gases of the requisite purity are described.