High‐purity chromium deposited from chromic acid electrolytes containing either sulfate or fluoride catalysts invariably contains small amounts of nitrogen as an undesirable impurity. The amount of this nitrogen impurity is shown to be increased by increased nitrate ion concentration in the electrolyte but not affected by dissolved atmospheric nitrogen or ammonium compounds. It is demonstrated that the nitrate impurity is decomposed at the cathode by reduction with hydrogen to form ammonia as the major product. Some of the atomic nitrogen which is possibly formed at a stage during this reduction is probably adsorbed continuously into the electrodeposited metal.