Absolute Rate Constants for the Reaction of Atomic Oxygen with Ethylene over the Temperature Range 232–500°K

1972 ◽  
Vol 56 (10) ◽  
pp. 4868-4876 ◽  
Author(s):  
Douglas D. Davis ◽  
Robert E. Huie ◽  
John T. Herron ◽  
Michael J. Kurylo ◽  
Walter Braun
Keyword(s):  
Rate Constants ◽  
Atomic Oxygen ◽  
Absolute Rate ◽  
Temperature Range

The reactions of atomic oxygen with 1-propanol and 2-propanol

1979 ◽  
Vol 57 (11) ◽  
pp. 1269-1273 ◽  
Author(s):  
A. L. Ayub ◽  
John M. Roscoe
Keyword(s):  
Rate Constants ◽  
Atomic Oxygen ◽  
Activation Energies ◽  
Steric Effects ◽  
Absolute Rate ◽  
Exponential Factors ◽  
The Absolute

The reactions of O(3P) with n-propanol and isopropanol were studied as a function of temperature. The absolute rate constants for these reactions, in the units M−1 s−1, obey the following relations.[Formula: see text]The activation energies of these reactions are similar to those of the corresponding reactions of methanol and ethanol, although some dependence on the strength of the α-C—H bond is discernible. The nearly constant pre-exponential factors for the reactions of methanol, ethanol, n-propanol, and isopropanol suggest that no special steric effects are present in the reactions of these compounds with O(3P). Mechanisms are discussed for the reactions of n-propanol and isopropanol with O(3P).

scholarly journals Absolute rate constant and O(<sup>3</sup>P) yield for the O(<sup>1</sup>D)+N<sub>2</sub>O reaction in the temperature range 227 K to 719 K

2008 ◽  
Vol 8 (20) ◽  
pp. 6261-6272 ◽  
Author(s):  
S. Vranckx ◽  
J. Peeters ◽  
S. A. Carl
Keyword(s):  
Rate Constant ◽  
Rate Constants ◽  
Room Temperature ◽  
Marked Decrease ◽  
Quantum Yields ◽  
Absolute Rate ◽  
Temperature Range ◽  
A Value ◽  
Relative Quantum ◽  
Absolute Rate Constant

Abstract. The absolute rate constant for the reaction that is the major source of stratospheric NOx, O(1D)+N2O → products, has been determined in the temperature range 227 K to 719 K, and, in the temperature range 248 K to 600 K, the fraction of the reaction that yields O(3P). Both the rate constants and product yields were determined using a recently-developed chemiluminescence technique for monitoring O(1D) that allows for higher precision determinations for both rate constants, and, particularly, O(3P) yields, than do other methods. We found the rate constant, kR1, to be essentially independent of temperature between 400 K and 227 K, having a value of (1.37±0.11)×10−10 cm3 s−1, and for temperatures greater than 450 K a marked decrease in rate constant was observed, with a rate constant of only (0.94±0.11)×10−10 cm3 s−1 at 719 K. The rate constants determined over the 227 K–400 K range show very low scatter and are significantly greater, by 20% at room temperature and 15% at 227 K, than the current recommended values. The fraction of O(3P) produced in this reaction was determined to be 0.002±0.002 at 250 K rising steadily to 0.010±0.004 at 600 K, thus the channel producing O(3P) can be entirely neglected in atmospheric kinetic modeling calculations. A further result of this study is an expression of the relative quantum yields as a function of temperature for the chemiluminescence reactions (kCL1)C2H + O(1D) → CH(A) + CO and (kCL2)C2H + O(3P) → CH(A) + CO, both followed by CH(A) → CH(X) + hν, as kCL1(T)/kCL2(T)=(32.8T−3050)/(6.29T+398).

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