| Popis: |
The reaction of oxygen atoms with amine radicals was studied directly by flash photolysisin a discharge-flow reactor. The decay of NH 2 radicals, produced by NH 3 + hv (λ>1700 )→NH 2 +H, in the presence of an excess of O atoms, O+NH 2 →HNO+H, (2′) →NH+OH, (2″) gave the rate constant k 2 =2.1×10 12 cm 3 /mole sec at 298°K. When NH 2 radicals were generated by H+NO 2 →NO+OH, OH+NH 3 →NH 2 +H 2 O, (11) k 11 =1.7×10 11 cm 3 /mole sec at 298°K, in a discharge-flow system coupled to a TOF mass spectrometer with nozzle-beam sampling, the rate of the reaction NO+NH 2 →N 2 +H 2 O * , (4) k 4 =5(±)×10 12 cm 3 /mole sec at 298°K, could be directly measured. Using a gold-coated Pyrex reaction vessel and monitoring the infrared chemiluminescence from Reaction (4), strong vibrational excitation of the H 2 O formed was observed. In addition to N 2 and H 2 O * , a small amount of NH 2 NO is produced in (4). Addition of 15 NO to the hydrazine/atomic oxygen reaction indicates that fission of the hydrazine N−N bond and formation of NO occur by O+N 2 H 2 →NO+NH 2 , (16′) →N 2 +OH+H, (16″) with about equal probability for (16′) and (16″). |
