leadIIIV

LeadIIIV is an informal designation for lead(II,IV) oxide, Pb3O4, a mixed-valence oxide that contains both lead in the +2 and +4 oxidation states. The name reflects the coexistence of two types of lead ions within a single compound, and the substance is commonly known in chemistry and materials contexts as red lead or minium.

Chemically, Pb3O4 can be viewed as PbO·PbO2, corresponding to two Pb2+ ions and one Pb4+ ion per formula unit. This mixed-valence composition influences its color, red to reddish-orange appearance, and its reactivity. The solid is relatively insoluble in water and can act as an oxidizing agent under certain conditions. It is more soluble in acids, where lead ions are released.

Production and historical use: Pb3O4 forms through partial oxidation of lead(II) oxide (PbO) or by combining PbO and PbO2 under controlled temperatures in air. Historically, red lead was produced and widely used as a pigment in paints and varnishes due to its bright color and opacity. It also served as a corrosion-resistant primer in industrial coatings. In modern times, concerns over lead toxicity have markedly reduced its use in consumer paints, and safer alternatives are preferred in most applications. It remains of interest in art restoration and certain niche industrial contexts, where its pigment properties are valued under strict safety controls.

Safety and regulation: Lead compounds pose significant health risks, particularly to children and pregnant individuals. Exposure can occur through inhalation or ingestion of dust or paint containing lead compounds. Consequently, Pb3O4 is subject to regulatory restrictions and requires careful handling, engineering controls, and appropriate disposal in regulated facilities.