摘要:

AbstractThe gas‐phase photochlorination of perfluorocyclopentene under continuous and intermittent illumination with 4360‐Å radiation was studied between 10° and 60°C. The rate constants for the reactions. (3)\documentclass{article}\pagestyle{empty}\begin{document}$$ C_5 F_8 CL + Cl_2 \to C_5 F_8 Cl_2 + Cl $$\end{document}(4)\documentclass{article}\pagestyle{empty}\begin{document}$$ 2C_5 F_8 Cl \to \Pr oducts $$\end{document}were measured ask3= (1.20 + 0.58) × 108exp (−6.430 ± 177/RT) l·(mole sec) andk4= (1.86 ± 0.76) × 10

ISSN:0538-8066    

DOI:10.1002/kin.550050302

出版商:John Wiley&Sons, Inc.    

年代:1973

数据来源: WILEY

摘要:

AbstractThe high‐pressure isotopic rate ratiokH/kDfor isomerisation of cyclopropylamine and cyclopropylamine‐N‐d2is 1.06 at 649–678 K, supporting a mechanism which does not involve migration of hydrogen from the amine group in the rate‐determi

ISSN:0538-8066    

DOI:10.1002/kin.550050303

出版商:John Wiley&Sons, Inc.    

年代:1973

数据来源: WILEY

摘要:

AbstractThe self‐radiolysis of mixtures of CO and tritium (3H2) has been studied at pressures of 0.25 to 1.0 atmospheres, temperatures of −198° to +100°C, and in the presence of added H2O or CO2. The products of decomposition are CO2,3H2O, C3H4, C23H4, and a white polymer believed to be polyformaldehyde. Initial rates andGvalues were measured and compared with rates of ion pair formation. The rates of formation of both CO2and C3H4are independent of temperature and proportional to the energy absorbed in t

ISSN:0538-8066    

DOI:10.1002/kin.550050304

出版商:John Wiley&Sons, Inc.    

年代:1973

数据来源: WILEY

摘要:

AbstractMeasurements of the rate of formation of methane in the thermal decomposition of ethane in dilute mixtures with argon were made by the shock tube technique. Derived values of the rate constant of the dissociation reaction are compared with earlier data of the same type and with recent shock tube data on the combination of methyl radicals. An RRKM calculation correlating all the data is described, from which an Arrhenius equation for the range 1000–1500°K, logk∞= 16.9 − 89,500/2.3RT, is ob

ISSN:0538-8066    

DOI:10.1002/kin.550050305

出版商:John Wiley&Sons, Inc.    

年代:1973

数据来源: WILEY

摘要:

AbstractThe kinetics of the gas‐phase decomposition of 1,2‐epoxycyclohexane has been studied over the temperature range 680–740 K at pressures between 1.6 and 6 torr. Isomerization to cyclohexanone and 2‐cyclohexen‐1‐ol accounts for ca. 97% of the primary reaction products and occurs by first‐order, homogeneous, nonradical processes:\documentclass{article}\pagestyle{empty}\begin{document}$$ k_{cyclohexanone} /s^{ - 1} = 10^{14.58 \pm 0.35} \exp \left( { - 60,300 \pm 1,100/1.987T} \right) $$\end{document}\documentclass{article}\pagestyle{empty}\begin{document}$$ k_{cyclohexanone - 1 - o1} /s^{ - 1} = 10^{13.11 \pm .41} \exp \left( { - 55,800 \pm 1,300/1.987T} \right) $$

ISSN:0538-8066    

DOI:10.1002/kin.550050306

出版商:John Wiley&Sons, Inc.    

年代:1973

数据来源: WILEY

摘要:

AbstractThe pyrolysis of 2,2‐dichloro‐1,1,1‐trifluoroethane was studied over the temperature range of 1120–1260°K at total reflected shock pressures from ∼2800 to 3100 torr. Below 1260°K, the decomposition leads to three reaction products which were identified as CF2CFCl, CF2CFH, and CF3CCl3. The results are interpreted in terms of a parallel CCl bond rupture process which becomes competitive with the molecular HCI elimination. The rate constant for the α,α‐elimination process\documentclass{article}\pagestyle{empty}\begin{document}$$ CF_3 CHCl_2 \to CF_2 CFCl + HCL $$\end{document}has been deduced to be\documentclass{article}\pagestyle{empty}\begin{document}$$ \log \left( {K_1 ^\infty /\sec ^{ - 1} } \right) = \left( {13.4 \pm 0.7} \right) - \left( {63.1 \pm 3.8kcal} \right)/2.303RT $$\end{document}It was also possible to obtain the overall rate constant for the formation of CF2CFH, which is given by\documentclass{article}\pagestyle{empty}\begin{document}$$ \log \left( {K^{''} /\sec ^{ - 1} } \right) = \left( {11.5 \pm 0.8} \right) - \left( {54.1 \pm 3.8kcal} \right)/2.303RT $$\end{document}Some evidence for hydrogen fluoride elimination was found at temperatures above 1260°K. However, at these higher temperatures CC bond scission also occurs and the kinetics of the syste

ISSN:0538-8066    

DOI:10.1002/kin.550050307

出版商:John Wiley&Sons, Inc.    

年代:1973

数据来源: WILEY

摘要:

AbstractUsing the technique of flash photolysis‐resonance fluorescence, absolute rate constants have been measured for the reaction of S(3P) with propene and 1‐butene. Variations in experimental conditions included the following: temperature (215–500°K); total pressure a factor of 10; olefin concentration, a factor of 6; flash intensity (S atom concentration), a factor of 10. It was found that over these variations in the experimental conditions only the temperature had a measureable effect on the bimolecular rate constant. The derived Arrhenius rate expressions for the reactions (2) and (3) were as follows:\documentclass{article}\pagestyle{empty}\begin{document}$$ k_2 = \left( {6.03 \pm 0.72} \right) \times 10^{ - 12} \exp \left( {\frac{{ - 0.38 \pm 0.09kcal/mol}}{{RT}}} \right) $$\end{document}temperature range 214–500°K\documentclass{article}\pagestyle{empty}\begin{document}$$ k_3 = \left( {7.41 \pm 1.15} \right) \times 10^{ - 12} \exp \left( {\frac{{ - 0.36 \pm 0.09kcal/mol}}{{RT}}} \right) $$\end{document}Units are cm3m

ISSN:0538-8066    

DOI:10.1002/kin.550050308

出版商:John Wiley&Sons, Inc.    

年代:1973

数据来源: WILEY

摘要:

AbstractAnalysis of the products from a vapor‐phase mixture of EtI andt‐BuI, in which free radicals were generated thermally, has yielded a rate constant for the recombination of 2t‐Bu⋅ of 105.4M−1sec−1at 100°C. The close agreement between this and other recent estimations from vapor‐phase work is noted, as is the disparity between these values and those on the order of 109M−1sec−1ob

ISSN:0538-8066    

DOI:10.1002/kin.550050309

出版商:John Wiley&Sons, Inc.    

年代:1973

数据来源: WILEY

摘要:

AbstractA new mechanism for gas phase ozone‐olefin reactions is proposed. The mechanism involves biradical intermediates which can react in a variety of ways. One of the possible reaction modes corresponds to the Criegie mechanism originally proposed to explain solution ozonolysis reactions and generally also accepted in the past for gas phase reactions. However, an examination of the gas phase data on ozone–olefin reactions and of the thermochemical and kinetic requirements for these reactions indicates that the Criegie reaction mode may be the least important of various other reaction possibilities. Those other reaction possibilities involve intramolecular H abstractions and rearrangements in biradical intermediates. The proposed mechanism provides very reasonable explanations for a number of unusual observations on gas phase ozonolysis. These are the formation of peroxidic bound products, aldehyde and 1,2‐dicarbonyl product fluorescences, and unexpected carbonyl product forma

ISSN:0538-8066    

DOI:10.1002/kin.550050310

出版商:John Wiley&Sons, Inc.    

年代:1973

数据来源: WILEY

摘要:

AbstractThe rate constant for the combination of 2,2‐dichloro‐1,1,1‐trifluoroethyl radicals has been measured by applying the rotating sector technique to the gas phase photochlorination of 2,2‐dichloro‐1,1,1‐trifluoroethane at 315°K. The observed value is 6.89 × 1012cc/mole.sec. This value is in excellent agreement with measurements by Wampler and Kuntz which yielded a temperature‐independent value of 6.6 × 1012cc/mole.sec. The measurement by Wampler and Kuntz was determined from the photochemical system (CF3CCl3+ C‐C6H12+ hν). The Arrhenius parameters for the reaction CF3CCl2· + Cl2→ CF3CCl3+ Cl were found to be given by the expression logk3= 12.10 − 5830/2.3RT(units in mole, cc, and sec). This is a relatively high activation energy for a chlorination reaction and makes the reaction ever slower than the ch

ISSN:0538-8066    

DOI:10.1002/kin.550050311

出版商:John Wiley&Sons, Inc.    

年代:1973

数据来源: WILEY