294.    ---------------. [BONE, W. A., AND COWARD, H. F.] Thermal Decomposition of Hydrocarbons.  I.  Methane, Ethane, Ethylene and Acetylene.  Jour. Chem. Soc., vol. 93-94, 1908, pp. 1197-1225; Proc. Chem. Soc., vol. 24, 1908, p. 167; Chem. Abs., vol. 2, 1908, p. 3061.

                  Results of a systematic investigation of the modes of decomposition of the 4 hydrocarbons 500°-1,200° were described.  CH₄, which is by far the most stable of the 4 hydrocarbons, and a principal product of the decomposition of the other 3, especially above 800°, decomposes for the main part into C and H₂.  The decomposition is, within the range investigated, a surface effect, and the C deposited is of a peculiarly hard and lustrous type.  Decomposition of the other 3 hydrocarbons takes place chiefly throughout the main body of the gas, with formation of large quantities of CH₄, which is explained on the supposition that residues such as ≡CH and =CH₂ (which may be considered to have momentary existence during the dissolution process), are directly hydrogenized in an atmosphere rich in H₂.  Assumption of the momentary formation of such residues (or the tendency to give rise to them, which actually becomes operative at moderately high temperatures) as the result of the initial dissolution of the hydrocarbon molecule, renders it possible to formulate a rational scheme of the chief causes at work and their modes of operation in each particular case.  It may be supposed that these residues are capable of (a) forming H₂C=CH₂ or HC≡CH as the result of encounters with other like residues, (b) breaking down directly into C and H₂, (c) combining with H₂ to form CH₄, and that all 3 possibilities may be realized simultaneously in proportions dependent on the temperature and the amount of H₂ present.