952.    ---------------.  [FISCHER, F.]  [Formation at Relatively Low Temperatures of Carbides Yielding Acetylene.]  Brennstoff-Chem., vol. 9, 1928, pp. 328-333; Chem. Abs., vol. 23, 1929, p. 2662.

     BaC₂ is prepared from BaO by heating with C in an electric porcelain-tube furnace in a stream of CH₄, with or without the addition of a small quantity of Fe₂O₃ and CaO.  BaC₂ yielding 60% of the theoretical C₂H₂, was obtained by heating a mixture of 2 gm. BaO+1 gm. CaO+0.2 gm.  Fe₂O₃ for 30 min. at 1,150° in CH₄ at 35 mm. pressure.  Carbides were not formed below 850° and yields fell sharply above 1,150°.  The highest yields were obtained in an atmosphere of CH₄.  The carbide formed at these low temperatures yields both H₂ and C₂H₂ with H₂O.  Fischer believes that free Ba is first formed by reduction, and this is partly converted into BaC₂ and partly into BaH₄.