Lead Oxide (Pb3O4)-Powder

Characteristic

Lead(II,IV) oxide, also called red lead or minium, is the inorganic compound with the formula Pb3O4. A bright red or orange solid, it is used as pigment, in the manufacture of batteries, and rustproof primer paints. It is an example of a mixed valence compound, being composed of both Pb(II) and Pb(IV) in the ratio of two to one.




Chemical formula：Pb3O4

Molar mass：685.6 g mol−1

Appearance：Vivid orange crystals

Density：8.3 g cm−3

Melting point：500 °C (decomposition)

Vapor pressure：1.3 kPa (at 0 °C)

Crystal structure：Tetragonal, tP28




Application

Red lead has been used as a pigment for primer paints for iron objects. Due to its toxicity, its use is being limited. It finds limited use in some amateur pyrotechnics as a delay charge and was used in the past in the manufacture of dragon's egg pyrotechnic stars.




Red lead is used as a curing agent in some polychloroprene rubber compounds. It is used in place of magnesium oxide to provide better water resistance properties.




Red lead was used for engineer's scraping, before being supplanted by engineer's blue.




It is also used as an adultering agent in turmeric powder.