133.    BAHR, H. A., AND JESSEN, V.  [Dissociation of Carbon Monoxide on Cobalt.]  Ber. deut. chem. Gesell., vol. 63B, 1930, pp. 2226-2237; Chem. Abs., vol. 25, 1931, p. 22.

                  Finely divided metallic Co does not dissociate CO at 225°.  The dissociation of CO takes place on the Co combined with 9.25% C as Co₂C.  At temperatures above 225°, Co₂C decomposes, giving free C.  No evidence of other Co carbides than Co₂C is found.  Co carbide prepared from CO dissociation on finely divided Co gives up its carbide C as CH₄ on treatment with H₂ at temperatures as low as 250°-250°, while the carbide prepared from free C + finely divided Co forms CH₄ on reacting with H₂ above 400°.