The Ketyl Radical in the Oxidation of Ethyne by Atomic Oxygen at 300-600 K

Article abstract of DOI:10.1021/j100249a028

The reaction of ethyne with atomic oxygen was investigated in the temperature range 300-600 K, at a pressure of 2 torr.With molecular beam mass spectrometry, both methylene and ketyl radical were shown to be important primary products.An absolute measurement was made of the rate constant of reaction 7 of HCCO with O at T = 535 K: k₇ = (1.10 +/- 0.10) X 10¹⁴ cm³ mol^-1 s^-1.The activation energy E₇ was found to be E₇ = 0.6 +/- 0.3 kcal mol^-1.Reaction 2 of HCCO with H atoms is even faster; in Stern-Volmer experiments the ratio k₂/k₇ was determined to be 1.4 +/- 0.4 at T = 535 K and 1.3 +/- 0.2 at T = 285 K.