699.    DEW, W. A., AND TAYLOR, H. S.  Adsorption and Heat of Adsorption of Ammonia Gas on Metallic Catalysts.  Jour. Phys. Chem., vol. 31, 1927, pp. 277-290; Chem. Abs., vol. 22, 1928, p. 1074.

     Measurements of the specific adsorption and heats of adsorption of NH₃ on Cu, Ni, and e catalysts have been made by methods previously used in order to study the reaction:  2NH₃=N₂+3H₂.  Values for the specific adsorption of NH₃ and H₂, and some figures for N₂ on Na, Cu, Ni, and Fe and 50-50 Fe-Mo at 0°, 110°, 218°, 305°, and 44.6°, with a number of exceptions, are given, which show that the catalysts adsorb NH₃, that the adsorption is reversible at low temperatures, and that decomposition occurs at higher temperatures.  Differential heats of adsorption for NH₃ at 0° on Cu, Ni, and Fe and integral heats for NH₃ at 0° on Cu and Ni have been given.  The beneficial effect of low-temperature preparation of catalysts upon the adsorption effect is stressed, and indication is found that the higher the heat of adsorption the greater the possibility of catalytic activity.