The decomposition of carbonyl fluoride (COF2), the reactions of carbonyl fluoride with carbon monoxide (CO), and the reactions of carbonyl fluoride with hydrogen (H2) in excess argon were studied behind reflected shock waves. Kinetic data were obtained in the temperature and total pressure ranges 2600–3300 °K and 2.5–9.0 atm, respectively, for the COF2 decompostion study, in the temperature and total pressure ranges 2400–3000 °K and 3.3–7.7 atm, respectively, for the COF2–CO study, and in the temperature and total pressure ranges 1900–2700 °K and 2–12 atm, respectively, for the COF2–H2 study. Under the experimental conditions, the bimolecular reaction between COF2 and CO was found to be negligible with respect to the decomposition of COF2. An empirical relationship for the over-all kinetics of the COF2–H2 reaction was determined, and a combined analytical and experimental study was conducted to determine a plausible mechanism for the COF2–H2 reaction. Under the experimental conditions, the dominant reaction steps in this mechanism were determined to be COF2+M →k1 COF+F+M, COF+M →k2 CO+F+M, H2+M → H+H+M, F+H2 → HF+H, H+COF2 →18 COF+HF, H+COF →20 CO+HF. In these studies an experimental value of k1 was obtained as k1 = 1014.25±0.24 exp(−77 200 ± 3300/RT) cc/mole⋅sec. The rate constant for Reaction 2 was derived based on experimental data, a steady state analysis, and an estimate of the ratio of the rate constants of Reactions 18 and 20. The derived value for k2 is given as k2 = 1015.0 exp(−49 000/RT) cc/mole⋅sec. The heat of formation of COF at absolute zero was determined to be approximately equal to −66 kcal/mole relative to the JANAF standard state definition.

The rate of decomposition of allyl iodide has been measured from 742°K to 1068°K and from 169 to 1429 torr using a shock tube method in which the disappearance of allyl iodide and the appearance of iodine are followed simultaneously. The kinetics are first order in allyl iodide and probably are slightly dependent upon total pressure. Mathematical modeling shows that they are compatible with a mechanism consisting of three reactions:(1,-1) (2,-2)The experiments yield the rate constant k,, the high-pressure limiting value of which is found to be logla k, (sec-I) = (14.45 f 0.4) -(42.8 f 2.4 kca1)/2.3RT in reasonable agreement with that predicted using the methods of Benson and O'Neal [l].

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Although sections of frozen salt solutions have been used as standards for x-ray microanalysis, such solutions are less useful when analysed in the bulk form. They are poor thermal and electrical conductors and severe phase separation occurs during the cooling process. Following a suggestion by Whitecross et al we have made up a series of salt solutions containing a small amount of graphite to improve the sample conductivity. In addition, we have incorporated a polymer to ensure the formation of microcrystalline ice and a consequent homogenity of salt dispersion within the frozen matrix. The mixtures have been used to standardize the analytical procedures applied to frozen hydrated bulk specimens based on the peak/background analytical method and to measure the absolute concentration of elements in developing roots.