Kinetic Study of the Formation and Reaction of CN Molecules in Shock Waves

The decomposition of gaseous BrCN in shock waves has been measured over the temperature range 2500–7000°K by following the light emitted by CN and C2. The rate of the reaction in 1 and 5% mixtures with Ar is —d[BrCN]/dt=2.0×1012T½ exp (—90.5 kcal mole—1/RT) [Ar] [BrCN] mole cc—1 sec—1. The subsequent disappearance of CN as determined by both the loss of CN and the formation of C2 is consistent with the reaction 2CN→C2+N2 for which the bimolecular rate constant is 1.6×1015 exp (—43 kcal mole—1/RT) cc mole—1 sec—1.