Determination of the Heat of Formation of Octafluorotoluene and Calculation of D[C6F5—F] – D[C6F5—CF3]

Abstract
The heat of formation of octafluorotoluene has been determined using the direct combustion method previously developed for hexafluorobenzene. As in the hexafluorobenzene case the combustion of octafluorotoluene in oxygen yields CO2, CF4, and F2. With a ten-fold excess of oxygen the CO2 to CF4 ratio is 3.85 ± 0.06. A full material balance was obtained. The value of ΔHf2980(C6F5CF3,g) = −303.2 ± 1.8 kcal mol−1 may be combined with the enthalpies of formation of C6F6, CF3, and F to give D[C6F5—F] – D[C6F5—CF3] = 55.7 ± 4.0 kcal mol−1.

This publication has 0 references indexed in Scilit: