Kinetics Database Logo

Kinetics Database Resources

Simple Reaction Search

Search Reaction Database

Search Bibliographic Database

Set Unit Preferences


Rate Our Products and Services


Other Databases

NIST Standard Reference Data Program

NIST Chemistry Web Book

NDRL-NIST Solution Kinetics Database

NIST Computational Chemistry Comparison and Benchmark Database

The NIST Reference on Constants, Units, and Uncertainty


Administrative Links

NIST home page

MML home page

Chemical and Biochemical Reference Data Division

MML home page

Chemical and Biochemical Reference Data Division

  NIST Logo Home
©NIST, 2013
Accessibility information
Author(s):   Elsamra, R.MI.; Vranckx, S.; Carl, S.A.
Title:   CH(A2«DELTA») formation in hydrocarbon combustion: The temperature dependence of the rate constant of the reaction C2H+O2 -> CH(A2«DELTA»)+CO2
Journal:   J. Phys. Chem. A
Volume:   109
Page(s):   10287 - 10293
Year:   2005
Reference type:   Journal article
Squib:   2005ELS/VRA10287-10293

Reaction:   ·C2H + O2 → CH(A2Delta, B2Sigma-) + CO2
Reaction order:   2
Temperature:   316 - 837 K
Pressure:  1.20E-2 - 1.33E-2 bar
Rate expression:   7.7x10-17 [cm3/molecule s] (T/298 K)4.40 e9562 [±1247 J/mole]/RT
Category:  Experiment
Data type:   Absolute value measured directly
Pressure dependence:   Rate constant is pressure independent
Experimental procedure:   Static or low flow - Data taken vs time
Excitation technique:   Flash photolysis (laser or conventional)
Time resolution:   In real time
Analytical technique:   Vis-UV emission
Comments:   195-nm photolysis of N2O used as source of O. C2H generated by photolysis of C2H2.
Lifetime of CH(A) in N2 also determined.
The preexponential factor based on rate constant for C2H + O(3P) -> CH(A) + CO of k = (1.0±0.5)x10-11exp(-230/T) cm3s-1 and the relative rate to this reaction at 250 K. This preexponential factor is considered uncertain to a factor of 10, but the relative rate constant k/k(300) is considered much more accurate.

View full bibliographic record.

Rate constant values calculated from the Arrhenius expression:

T (K)k(T) [cm3/molecule s]
316 3.79E-15
350 4.18E-15
400 4.98E-15
450 6.08E-15
500 7.49E-15
550 9.24E-15
600 1.14E-14
650 1.40E-14
700 1.71E-14
750 2.07E-14
800 2.50E-14
837 2.86E-14