I. Kinetics of the Thermal Decomposition of Nitrogen Dioxide Behind Shock Waves. II. Kinetics of the Ferrous Ion-Oxygen Reaction in Sulfuric Acid Solution

Year: 1958

DOI: 10.7907/53F3-0D68

NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document.

Shock waves into argon containing a small amount of N02 have been used to study the kinetics of the thermal decomposition of nitrogen dioxide from 1100 to 2300[degrees]K. Mole fractions of N02 varied from 2.8 x 10[...] to 1.5 x 10[...]; the ratio argon/N02 varied from 5.6 to 350; the argon concentration varied by a factor of twenty; and the N02 concentration varied by a factor of ten. Under these conditions, the results indicate that two separate reaction mechanisms are operative. One path has the rate law [...] with [...] and is apparently the unimolecular decomposition of N02 at the second order limit. The other path has the rate law [...] with an activation energy of 22[plus or minus]6 kcal/mole. This path is believed to be the bimolecular decomposition of N02 first observed by Bodenstein. However, extrapolation of this mechanism to the shock tube temperatures gives results about eight times too low. The reason for this discrepancy is not known. One interpretation is that there is another bimolecular reaction path for the decomposition of N02. A good possibility for such a path is the bimolecular formation of N02, recently postulated by Ashmore and Levitt, and its subsequent rapid decomposition, either by reaction with N02 or by unimolecular dissociation into N02 and 0. This discrepancy has also recently been observed by Steinburg and Lyon in a concurrent investigation. However, the mechanism and conclusions of that study are not supported by the present investigation.

Part II consists of a paper that has already been published on the kinetics of the ferrous ion-oxygen reaction in sulfuric acid solution.