ISSN:
1089-7690
Source:
AIP Digital Archive
Topics:
Physics
,
Chemistry and Pharmacology
Notes:
The reaction between OH and C6H6 in He has been studied over the pressure range 250–500 Torr and the temperature range 345–385 K by means of the laser-photolysis/laser-induced-fluorescence technique. Analysis of the temporal profile of [OH] yielded the detailed rate coefficients and the equilibrium constant for the reaction OH+C6H6+M↔HOC6H6+M. The temperature dependence of the rate coefficients for the forward, the reverse, and the adduct-loss reactions have been determined to be kf=(2.0±0.1)×10−14 exp[(1420±250)/T] cm3 molecule−1 s−1, kr=(3.0±0.2)×1012 exp[−(8240±320)/T] s−1, and ka=(1.7±0.3)×106 exp[−(3500±360)/T] s−1, respectively. The temperature dependence of the equilibrium constant led to the enthalpy of reaction ΔH(365±20 K)=−(20.0±1.2) kcal mol−1 and the entropy of reaction ΔS(365±20 K)=−(33.6±2.5) cal K−1 mol−1, greater than previously reported values; after correction for temperature dependence, ΔH0(298 K)=−(19.9±1.2) kcal mol−1 and ΔS0(298 K)=−(33.4±2.6) cal K−1 mol−1.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.467717
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