3331.     TAYLOR, G. B., AND STARKWEATHER, H. W.  Reduction of Metal Oxides by Hydrogen.  Jour. Am. Chem. Soc., vol. 52, 1930, pp. 2314-2325; Chem. Abs., vol. 24, 1930, p. 3944.

        Method is described for studying the rate of reduction of metal oxides at temperatures below 500 in which the volume of H2 consumed is measured.  The oxides of Ni, Cu, Fe, and Zn were studied by this method.  Fe2O3 gels are reduced to ferroso-ferric oxide at 350 and to metallic Fe at 450.  Ignited Fe2O3 is not appreciably reduced at 350 but goes to metal at 450.  Foreign metal interfaces with Fe2O3 accelerate the reduction of Fe.  Al2O3 and Cr2O3 greatly retard the reduction of ferroso-ferric oxide.  Fe2O3 gels show the glow phenomenon in H2 at fairly low temperatures but not in air or vacuum.  The thermodynamics of ZnO reduction in the presence of Cu are worked out, giving an explanation of the formation of a-brass.

        TAYLOR, H. G.  See abs. 3305a.