Barium Orthoplumbate, Ba₂PbO₄

Barium Orthoplumbate, Ba₂PbO₄, is obtained as a black compound by gently heating lead oxide with barium oxide or barium carbonate in air at bright red heat. It is insoluble in water, but is decomposed by long contact with it. With hydrochloric acid it gives chlorine, and with other acids lead peroxide.