Sodium persulphate

Sodium peroxide is the inorganic compound with the formula Na₂O₂. This yellowish solid is the product of sodium ignited in excess oxygen. It is a strong base. This metal peroxide exists in several hydrates and peroxyhydrates including Na₂O₂·2H₂O₂·4H₂O, Na₂O₂·2H₂O, Na₂O₂·2H₂O₂, and Na₂O₂·8H₂O. The octahydrate, which is simple to prepare, is white, in contrast to the anhydrous material.