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  • Chemistry  (8)
  • 1
    Electronic Resource
    Electronic Resource
    The kinetics and the mechanism of the thermal decomposition of bis-pentafluorosulfurtrioxide (SF5OOOSF5) (1979)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 11 (1979), S. 613-619 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The thermal decomposition of SF5O3SF5 has been investigated between 5 and 25°C. In the presence of sufficient high pressures of O2 the only products formed are SF5O2SF5 and O2: \documentclass{article}\pagestyle{empty}\begin{document}$$ {\rm SF}_5 {\rm O}_3 {\rm SF}_5 { } \to { SF}_{5} {O}_{2} {SF}_{5} { + (}{\raise0.5ex\hbox{$\scriptstyle {1}$} \kern-0.1em/\kern-0.15em\lower0.25ex\hbox{$\scriptstyle {2}$}}{) O}_{2} {, }\Delta n{ = }{\raise0.5ex\hbox{$\scriptstyle {1}$} \kern-0.1em/\kern-0.15em \lower0.25ex\hbox{$\scriptstyle 2$}} $$\end{document} The reaction is homogeneous. Its rate is strictly first order with respect to the trioxide pressure and independent of the total pressure of the reaction products and of oxygen above a certain limiting pressure: \documentclass{article}\pagestyle{empty}\begin{document}$$ - \frac{{{\rm d}[{\rm SF}_5 {\rm O}_3 {\rm SF}_5 ]}}{{{\rm dt}}}{ = + }\frac{{{\rm d}[{\rm SF}_5 {\rm O}_2 {\rm SF}_5 ]}}{{{\rm dt}}}{ = 2}\frac{{{dp}}}{{{\rm dt}}}{ = k[SF}_{5} {O}_{3} {SF}_{5} {]} $$\end{document} The experimental results can be explained with the following mechanism: In the presence of O2 〉 100 Torr the concentration of SF5 is insignificantly small. Therefore reactions (5) and (6) do not have to be considered any more, and steps (2) and (2′) will be of no importance. From reactions (1)-(4) it follows: \documentclass{article}\pagestyle{empty}\begin{document}$$ - \frac{{d[{\rm SF}_{\rm 5} {\rm O}_{\rm 3} {\rm SF}_{\rm 5} ]}}{{dt}} = + \frac{{d[{\rm SF}_{\rm 5} {\rm O}_{\rm 2} {\rm SF}_{\rm 5} ]}}{{dt}} = k_1 \frac{{[{\rm SF}_{\rm 5} {\rm O}_{\rm 3} {\rm SF}_{\rm 5} ]}}{{1 + k'_1 (1/2k_3 k_4 )^{1/2} }}k({\rm sec}^{{\rm - 1}}) = k_1 /\left[ {1 + k'_1 \left({\frac{1}{{2k_3 k_4 }}} \right)^{1/2} } \right] = 10^{16.06 \pm 0.37} {\rm exp( - 26,000} \pm {\rm 500}\,{\rm cal)/1}{\rm .987 }T $$\end{document}The numerical value of the factor [1 + (k′12/2k3k4)1/2] is small. It can be estimated that E3 ≃ 2 ± 1 kcal; therefore, E - E1 ≤ 1 kcal, and D (SF5O—O2SF5) = (26 - 1) ± 1.0 kcal.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550110608
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  • 2
    Electronic Resource
    Electronic Resource
    The kinetics and the mechanism of the thermal gas-phase reaction between NO2 and 1,1-dichlorodifluoroethylene, CF2CCl2 (1986)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 18 (1986), S. 907-917 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of the gas phase reaction between NO2 and CF2CCl2 has been investigated in the temperature range from 50 to 80°C. The reaction is homogeneous. Three products are formed: O2NCF2CCl2NO2 and equimolecular amounts of CINO and of O2NCF2C(O)Cl. The rate of consumption of the reactants is independent of the total pressure, the reaction products, and added inert gases and can be represented by a second-order reaction: \documentclass{article}\pagestyle{empty}\begin{document}$$ - \frac{{d[{\rm NO}_{\rm 2}]}}{{dt}} = - 2\frac{{d[{\rm CF}_{\rm 2} {\rm CCI}_{\rm 2}]}}{{dt}} = k[{\rm NO}_{\rm 2}][{\rm CF}_{\rm 2} {\rm CCI}_{\rm 2}] $$\end{document}However, the distribution of the products is influenced by the pressure of the present gases, which favor the formation of the dinitro-compound in a specific way. The effect of CF2CCl2 is the greatest. In the absence of added gases, the ratio of O2NCF2CCl2NO2 to that of O2NCF2C(O)Cl is proportional to (CF2CCl2 + γP products).The experimental results can be explaned by the following mechanism: P and X represent the products and the added gases: \documentclass{article}\pagestyle{empty}\begin{document}$$ - \frac{{d[{\rm NO}_{\rm 2}]}}{{dt}} = - 2\frac{{d[{\rm CF}_{\rm 2} {\rm CCI}_{\rm 2}]}}{{dt}} = k_1 [{\rm NO}_{\rm 2}][{\rm CF}_{\rm 2} {\rm CCI}_{\rm 2}] $$\end{document} \documentclass{article}\pagestyle{empty}\begin{document}$$ k_1 = 3.16 \pm 0.5 \times 10^6 \exp ( - 10500 \pm 1000{\rm cal/}RT){\rm M}^{{\rm - 1}} {\rm s}^{{\rm - 1}} $$\end{document} \documentclass{article}\pagestyle{empty}\begin{document}$$ {\rm \gamma }_{{\rm CF}_{\rm 2} {\rm CCI}_{\rm 2} } :{\rm \gamma }_P :{\rm \gamma }_{{\rm C}_{\rm 2} {\rm F}_{\rm 5} {\rm CI}} :{\rm \gamma }_{{\rm CCL}_{\rm 3} } :{\rm \gamma }_{{\rm CF}_{\rm 4} } :{\rm \gamma }_{{\rm N}_{\rm 2} } = 1:0.22:0.15:0.14:0.054:0.015 $$\end{document} \documentclass{article}\pagestyle{empty}\begin{document}$$ {\rm \gamma }_{{\rm NO}_{\rm 2} } 〈 0.01 $$\end{document} \documentclass{article}\pagestyle{empty}\begin{document}$$ k_3 = 1.4 \pm 0.3 \times 10^8 {\rm s}^{{\rm - 1}} $$\end{document}
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550180810
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  • 3
    Electronic Resource
    Electronic Resource
    The kinetics and the mechanism of the thermal gas-phase reaction between bis(trifluoromethyl)trioxide, CF3O3CF3 and 1,1-dichlorodifluoroethylene, CF2CCI2 (1986)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 18 (1986), S. 1323-1331 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The thermal addition of CF3O3CF3(T) to CF2CCl2(E) has been investigated between 49.6 and 69.5°C. The initial pressure of CF3O3CF3 was varied between 7 and 240 torr and that of CF2CCl2 between 4 and 600 torr. Four products of formula CF3O(E)j OOCF3, where j = 1 → 4 are formed. The sum of the products Σi = 14 CF3O(E)jOOCF3 is equal to the amount of trioxide decomposed.The reaction is homogeneous. Its rate is not affected by the total pressure and the presence of inert gas. It is a free radical telomerization with four basic steps: thermal decomposition of CF3O3CF3 into CF3O. and CF3O2., chain initiation by addition of CF3O. to olefin incorporated in, and telomeric radicals termination.The consumption of alkene is well represented by the equation: \documentclass{article}\pagestyle{empty}\begin{document}$$ - d[E]/dt = k_1 [T]\left\{ {1 + \sum\limits_{j = 1}^3 {\prod\limits_{i = 1}^j {[1 + (k_{t_1 } k_1^{1/2} /k_{gi} } k_t^{1/2})([T]^{1/2} /[E])]^{ - 1} } } \right\} $$\end{document} where (d[E]/d[T]) = \documentclass{article}\pagestyle{empty}\begin{document}$$ \bar n $$\end{document} is the mean chain length of telomerization. \documentclass{article}\pagestyle{empty}\begin{document}$$ \bar n $$\end{document} varies from 1.45 at 1.5 torr of E to 3.3 at 400 torr of E. Above this pressure E has no influence on \documentclass{article}\pagestyle{empty}\begin{document}$$ \bar n $$\end{document}.The estimated value of the constant for the addition of telomeric radicals to alkene is:\documentclass{article}\pagestyle{empty}\begin{document}$$ k_g \simeq 8.6 \pm 6.0 \times 10^4 \exp ( - 2300 \pm 200{\rm col mol}^{{\rm - 1}} /RT){\rm M}^{{\rm - 1}} {\rm s}^{{\rm - 1}} $$\end{document}
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550181204
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  • 4
    Electronic Resource
    Electronic Resource
    Kinetics of the thermal decomposition of bis-pentafluorine sulfur peroxide in the presence of carbon monoxide (1978)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 10 (1978), S. 111-116 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The thermal decomposition of F5SOOSF5, P, in the presence of CO has been investigated between 130.1° and 161.9°C at total pressures between 50 and 600 torr. The reaction is homogeneous, and the only final products formed are CO2 and S2F10. The rate of reaction is proportional to the pressure of P. The partial pressures of CO and O2 and the total pressure have no influence on the course of reaction: \documentclass{article}\pagestyle{empty}\begin{document}$$ - \frac{{d\left[P \right]}}{{dt}} = k\left[P \right] $$\end{document}The results are explained by the following mechanism:
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550100109
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  • 5
    Electronic Resource
    Electronic Resource
    Kinetics and mechanism of the thermal gas-phase reaction between NO2 and trichloroethene at 303-362.2 K (1992)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 24 (1992), S. 679-687 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of the gas-phase reaction between NO2 and trichloroethene has been investigated in the temperature range 303-362.2 K. The pressure of NO2 was varied betwen 5.1 and 48.7 torr and that of trichloroethene between 7.3 and 69.5 torr. The reaction was homogeneous. Two products were formed: nitrosyl chloride, ClNO, and glyoxyloxyl chloride, HC[O]C[O]Cl, which was identified by its infrared spectrum and its molecular weight determined by chromatography. The rate of consumption of the reactants was independent of the total pressure and can be represented by a second-order reaction: \documentclass{article}\pagestyle{empty}\begin{document}$$ -d[{\rm NO}_2]/dt = - 2d[{\rm CHClCCl}_2]/dt = k[{\rm NO}_2][{\rm CHClCCl}_2] $$\end{document} The following mechanism was proposed to explain the experimental results: The following expression was obtained for k: \documentclass{article}\pagestyle{empty}\begin{document}$$ k= 2k_1 k_3/[k_2 + k_3] = 4.07 \pm 1.2 \,\times\, 10^2 \exp [-8800\, \pm\, 800\,{\rm cal\,mol}^{-1}/ RT]1\,{\rm mol}^{-1}\,{\rm s}^{-1} $$\end{document}. © John Wiley & Sons, Inc.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550240708
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  • 6
    Electronic Resource
    Electronic Resource
    Kinetics of the thermal decomposition of bis-pentafluorosulfur trioxide(SF5O3SF5) in the presence of carbon monoxide (1979)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 11 (1979), S. 1089-1096 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The thermal decomposition of SF5O3SF5 in the presence of CO has been investigated between -9.8°C and + 9.9°C. Besides traces of S2F10, equimolecular amounts of SF5O2SF5 and CO2 are formed. \documentclass{article}\pagestyle{empty}\begin{document}$$ {\rm SF}_{\rm 5} {\rm O}_{\rm 3} {\rm SF}_{\rm 5} {\rm + CO } \to {\rm SF}_{\rm 5} {\rm O}_{\rm 2} {\rm SF}_{\rm 5} {\rm + CO}_{\rm 2}{\rm,}\Delta _n {\rm = 0} $$\end{document} The reaction is homogeneous. Its rate is proportional to the pressure of the trioxide and in dependent of the total pressure, the pressure of inert gases and of carbon monoxide: \documentclass{article}\pagestyle{empty}\begin{document}$$ - {\rm }\frac{{d[{\rm SF}_5 {\rm O}_{\rm 3} {\rm SF}_5 ]}}{{dt}}{\rm = +}\frac{{d[{\rm SF}_5{\rm O}_{\rm 2} {\rm SF}_5 }}{{dt}} = {\rm}k[{\rm SF}_5 {\rm O}_{\rm 3}{\rm SF}_5 ] $$\end{document} where k = k1∞ = 1016.32±0.40 exp(-25,300 ± 500 cal)/RT sec-1. Consequently, \documentclass{article}\pagestyle{empty}\begin{document}$$ {\rm D}_{{\rm SF}_{\rm 5} {\rm O - O}_{\rm 2} {\rm SF}_{\rm 5}} {\rm =}25.3{\rm}\pm {\rm 0}{\rm .5 kcal} $$\end{document} In the presence of oxygen a sensitized CO2 formation is observed. A mechanism is given which explains the experimental results.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550111007
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  • 7
    Electronic Resource
    Electronic Resource
    The kinetics and the mechanism of the thermal decomposition of bis(trifluoromethyl) trioxide. The influence of carbonmonoxide on its decomposition (1981)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 13 (1981), S. 639-649 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of the thermal decomposition of CF3O3CF3 has been investigated in the pressure range of 15-599 torr at temperatures between 59.8 and 90.3°C and also in the presence of CO between 42 and 7°C. The reaction is homogeneous. In the absence of CO the only reaction products are CF3O2CF3 and O2. The rate of reaction is strictly proportional to the trioxide pressure, and is not affected by the total pressure, the presence of inert gases, and oxygen. \documentclass{article}\pagestyle{empty}\begin{document}$$ -\frac{{d[{\rm CF}_{\rm 3} {\rm O}_{\rm 3} {\rm CF}_{\rm 3}]}}{{dt}} = 2\frac{{dp}}{{dt}} = k[{\rm CF}_{\rm 3} {\rm O}_{\rm 3}{\rm CF}_{\rm 3}] $$\end{document} \documentclass{article}\pagestyle{empty}\begin{document}$$ k = 2.25 \pm 0.18 \times 10^{15} \exp (- 30,530 \pm 130\,{\rm cal}/RT)s^{ - 1} $$\end{document}The following mechanism explains the experimental results: In the presence of CO there appear CO2, (CF3OCO)2, and CF3O2C(O)OCF3 as products. With increasing temperature the amount of peroxicarbonate decreases, while the amounts of oxalate and CO2 increase. The rate of decomposition of the trioxide above a limiting pressure of about 10 torr CO is strictly first order and independent of CO pressure, total pressure, and the pressure of the products. \documentclass{article}\pagestyle{empty}\begin{document}$$ - \frac{{d[{\rm CF}_{\rm 3} {\rm O}_{\rm 3} {\rm CF}_3]}}{{dt}} = k*[{\rm CF}_{\rm 3} {\rm O}_{\rm 3} {\rm CF}_{\rm 3}] $$\end{document} The addition of larger amounts of O2 to the CO containing system chaqnges the course of the reaction.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550130705
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  • 8
    Electronic Resource
    Electronic Resource
    Kinetics and mechanism of the thermal gas-phase reaction between trifluoromethylhypofluorite, CF3OF, and tetrachloroethene (1996)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 28 (1996), S. 489-495 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The thermal gas-phase reaction of CF3OF with CCl2CCl2 has been studied between 313.8 and 343.8 K. The initial pressure of CF3OF was varied between 10.8 and 77.5 torr and that of CCl2CCl2 between 3.7 and 26.8 torr. CF3OF was always present in excess, varying the initial ratio of CF3OF to that of CCl2CCl2 from 1.3 to 10. Three products were formed: CF3OCCl2CCl2F, CCl2FCCl2F, and CF3O(CCl2CCl2) 2OCF3. The yields of CF3OCCl2CCl2F were 98-99.5%, based on the sum of the products. The reaction was a homogeneous chain reaction not affected by the total pressure. In presence of O2 the oxidation of CCl2CCl2 to CCl3C(O)Cl and COCl2 occurred. The proposed basic reaction steps are: generation of the radicals CF3O· and CCl2FCCl2· (κ1) in a biomolecular process between CF3OF and CCl2CCl2, formation of the radical CF3OCCl2CCl2· by addition of CF3O· to CCl2CCl2, chain generation of CF3O· by abstraction of fluorine atom from CF3OF by CF3OCCl2CCl2· (κ4), and chain termination by recombination of the radicals CF3OCCl2CCl2·. The expressions obtained for the constants κ1 and κ4 are κ1 = 3.16 ± 0.6 × 107 exp(-15.2 ± 1.7 Kcal mol-1/RT) dm3 mol-1 s-1, κ4 = 3.7 ± 0.5 × 109 exp(-6.0 ± 1.1 Kcal mol-1/RT) dm3 mol-1 s-1. © 1996 John Wiley & Sons, Inc.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.3
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