A coulometric technique using a polarograph was used to study the oxidation of hydrogen at platinized platinum electrodes. The results obtained by this technique are in agreement with results obtained by charging curve and a‐c bridge techniques. This technique showed the presence of two forms of hydrogen adsorbed at the surface of the platinum, and it also showed the presence of hydrogen absorbed in the platinum. A study of the effect of pH on the current voltage curves suggested that absorbed hydrogen migrated as a charged species, probably .