The NO- and NO2-catalyzed decomposition of I2 in shock waves

✍ Scribed by H. Hippler; K. Luther; H. Teitelbaum; J. Troe

• Publisher: John Wiley and Sons
• Year: 1977
• Tongue: English
• Weight: 701 KB
• Volume: 9
• Category: Article
• ISSN: 0538-8066
• DOI: 10.1002/kin.550090607

✦ Synopsis

Measurements of the NO-catalyzed dissociation of I2 in Ar in incident shock waves were carried out in the temperature range of 700"-1520°K and a t total concentrations of 5 X 10-6-6 X mol/cm3, using ultraviolet-visible absorption techniques to monitor the disappearance of 12. It was shown that the main reaction responsible for the disappearance under these conditions is I2 + NO -I N 0 + I, for which a rate coefficient of (2.9 f 0.5) X 1013 exp[-(18.0 f 0.6 kcal/mol)/RT] cm2/ mol-sec was determined. The I N 0 formed dissociates rapidly in a subsequent reaction. The reaction, therefore, constitutes a "chemical model" for a "thermal collisional release mechanism."

Preliminary measurements of the rate coefficient for 12 + NO2 -IN02 + I are also presented.

Combined with information on the reverse reactions obtained in earlier room temperature experiments, these results lead to accurate values of AH; for I N 0 and IN02 equal to 29.7 f 0.5 and 15.9 f 1 kcal/mol, respectively.