Silver(I) oxide
Silver(I) oxide is a chemical compound with the formula Ag2O. It is a fine black or dark brown powder. It is composed of silver in the +1 oxidation state. It is used in silver oxide batteries to oxidize the zinc, providing the electrical current. It is more expensive than the mercury(II) oxide used in mercury batteries but much less toxic and less damaging to the environment. It can react violently with reducing agents.