429.    ---------------.[CANTELO, R. C.]  Methane Equilibrium.  II.  Jour. Phys. Chem., vol. 31, 1927, pp. 124-130; Chem. Abs., vol. 21, 1927, p. 849.

                  Equilibrium constants for the reactions that might conceivably occur along with the thermal decomposition of C₂H₄ are calculated by means of the Nernst approximation formula.  The calculations are tabulated for 200°, 400°, 600°, and 800°.  The reactions with their increase in heat content are:  C₂H₄=2C+2H₂-14,600 cal.; C₂H₄=C₂H₂+H₂ +43,500 cal.; 3C₂H₄=C₆H₆+3H₂-32,500 cal.; C₂H₆=2C+3H₂+23,300 cal.; C₂H₆=C₂H₄+ H₂+37,900 cal.; C₂H₆=C₂H₂+2H₂+81,400 cal.; 3C₂H₂=C₆H₆-163,000 cal.; CH₄=C+2H₂+ 18,900 cal.; 2CH₄=C₂H₄+2H₂+52,400 cal.; 2CH₄=C₂H₂+3H₂+95,900 cal.  From a consideration of the equilibrium constants it appears that whether the initial system be CH₄, C₂H₄, or C₂H₆, the final equilibrium system will be CH₄, C, and H₂ in the proportions to satisfy this equilibrium.  A brief review of the experimental work upon C₂H₄ and C₂H₆ decomposition shows that the above conclusion is supported by the experimental evidence.