The “oxygen” adsorption on polycrystalline was studied between 0.4 and 1.43v vs. SCE at 5°, 25°, and 50°C, using cathodic galvanostatic stripping and rapid single pulse differential capacity measurements. A potential arrest at 0.5v is ascribed to surface and/or Au‐O formation, a plateau at 1.0v to surface oxidation to , probably occurring in patches. The appearance of a maximum in the differential capacity‐potential curve during the adsorption process is explained on the basis of an additional capacity, , of the inner double layer due to the presence of the charges of the (specifically) adsorbed species. It is shown that should be proportional to the slope of a plot of amount adsorbed vs. potential. The model proves satisfactory for surface build‐up to 1/3 of a monolayer, and on decomposition from a monolayer.