ISSN:
0538-8066
Schlagwort(e):
Chemistry
;
Physical Chemistry
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Chemie und Pharmazie
Notizen:
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.
Zusätzliches Material:
2 Ill.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1002/kin.550130705
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