3332.     TAYLOR, H. S.  [Active Centers on Catalysts.]  Ztschr. Elektrochem., vol. 35, 1929, pp. 542-549; Chem. Abs., vol. 23, 1929, p. 5395.

        Measurements of heats of adsorption of gases on metal and metal oxide catalysts are discussed.  The difficulty in explaining the observed maximum in heats of adsorption is considered.  It is emphasized that the energy of activation of a surface reaction is dependent on the preparation of the contact substance.  It is possible that for a given reaction the energy of activation is smaller the more active the catalyst.  Measurements of heats of adsorption together with reactions studied on poisoned and nonpoisoned catalysts demonstrate the existence of centers for different activity on a catalyst.  A specific effect on the reacting molecules is exerted only by certain well-defined areas of the macroscopic surface.