Journal Articles (before-1995)

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    Bond dissociation energies from equilibrium studies: Part 4.—The equilibrium Br2+ CH4⇌ HBr + CH3Br. Determination of D(CH3—Br) and ΔH °f(CH3Br, g)
    (Journal of the Chemical Society : Faraday Transaction - I. The Chemical Society, London. 1973, 69 (2), 1973) Ferguson, K. C.; Okafo, E. N.; Whittle, E.
    The equilibrium Br2+ CH4⇌ HBr + CH3Br (2) has been studied in the range 347–477°C, with equilibrium being approached from both sides. Products additional to those required by eqn (2) were formed but it is believed that reliable values of the equilibrium constant K2 have been measured. Third-law calculations lead to ΔH°2=–26.4 ± 0.7 kJ mol–1 at 298 K from which ΔH°f(CH3Br, g)=–34.3 ± 0.8 kJ mol–1.
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    Chlorine Abstraction Reactions of Fluorine: Part 2.—The Kinetic Determination of the Bond Dissociation Energy Di (CC12F—Cl)
    (Journal of the Chemical Society : Faraday Transaction - I. The Chemical Society, London. 1972, 68 (1), 1972) Foon, Ruby; Tait, K. B.
    The reaction of fluorine with CCl3F has been studied over the temperature range 491–586 K. The mechanism is identical to that found in Pyrex vessels except that the reaction is now a homogeneous gas phase one. The rate equation has the form: –d[CCl3F]/dt=k[F2]½[CCl3F]. The rate constants fitted the Arrhenius equation: log k(1.½ mol–½ s–1)=(11.95 ± 0.07)–(31490 ± 90)/2.303 RT where k=k2(Kc)½, k2 is the rate constant for the reaction F + CCl3F → ClF + CCl2F and kc is the equilibrium constant for the homogeneous gas phase dissociation of fluorine. This leads to D°0(CCl2F—Cl)= 72 ± 2 kcal mol–1 and ΔH°f0(CCl2F)=–24 ± 4 kcal mol–1. The temperature dependence of the ignition limits has been investigated, and treated by thermal explosion theory. The ignitions are shown to be the result of radical branching reactions brought about by the collisional deactivation of vibrationally excited CCl2F2 molecules. Induction periods were also observed and studied.