A mathematical analysis of the working mechanism of the Teflon‐bonded gas diffusion electrode, based on the concept of “flooded agglomerates,” is discussed. This model is used to predict the performance of the electrode as a function of such measurable physical characteristics as intrinsic activity of catalyst, agglomerate size, internal porosity, real surface area, etc. The alkaline oxygen electrode is taken as an example for the discussion.

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REDUCTION OF C1 ON C 1161Studies of the mechanism of chlorine evolution on graphite (9) in molten lithium chloride suggests, as the rate determining step, the combination of chlorine atoms on a surface with appreciable coverage. In fact, when scanning the rotating carbon electrode from the region of chlorine evolution to more cathodic potentials, one indeed observes, up to overvoltages of 250 mV, a lower Tafel slope which changes to 2RT/F at higher overvoltages probably indicating the change from an intermediate to low coverage. On the anodic going sweep, this low coverage is maintained until reaching anodic potentials. Thus, we can conclude that the chlorine reduction on vitreous carbon in AlCls-KC1-NaC1 melts occurs according to path 1 with step la being most probably rate determining at higher polarizations with a low chlorine coverage on the electrode.

The kinetics of the anodic oxidation of glucose in a calcium‐free, Krebs‐Ringer bicarbonate buffer solution at 37°C was studied with a platinized platinum rotating‐disk electrode. Potentiostatic measurements were performed over a potential range of −200 to about 200 mV vs. the saturated calomel electrode (SCE). Excellent reproducibility was achieved by activating the electrode prior to each measurement by an electrochemical pulsing procedure, The current‐time curves did not attain a steady‐state value even after several hours, suggesting that a slow deactivation of the electrode was occurring during the glucose oxidation reaction. Over a limited potential range the current decay exhibited a logarithmic dependence on time. This behavior was interpreted in terms of adsorption of an inhibiting species according to the Elovich equation. The variation of glucose oxidation rate as a function of electrode rotation rate showed that the reaction was predominantly activation controlled. Calculated values of n , the over‐all charge transfer number for glucose oxidation, were dependent upon both potential and time and ranged from about 4 to 20 under the conditions studied.