5407. Lead Dioxide

Nomenclature

CAS number: 1309-60-0
Lead oxide (PbO2); lead (IV) oxide; lead oxide brown; lead peroxide; lead superoxide; plumbic oxide.
O2Pb; mol wt 239.20.
O 13.38%, Pb 86.62%.

Description and references

Occurs in nature as the mineral plattnerite. Lab prepn from lead acetate and calcium hypochlorite: Newell, Maxson, Inorg. Synth. 1, 45 (1939); by hydrolysis of lead acetate: Kuhn, Hammer, Ber. 83, 413 (1950). Review of toxicology: B. Venugopal, T. D. Luckey, Environ. Qual. Safety Suppl. 1, 4-73 (1975).

Properties

Dark-brown powder; evolves oxygen when heated, first forming Pb3O4, at high temp PbO. d 9.38. Oxidizer. Insol in water. Sol in HCl with evolution of Cl; in dil HNO3 in presence of H2O2, oxalic acid, or other reducers; sol in alkali iodide solns with liberation of iodine; soluble in hot caustic alkali solns. LD50 i.p. in guinea pigs: 220 mg/kg (Venugopal, Luckey).

Use

Electrodes in batteries; oxidizing agent in manuf dyes; as discharge in dyeing with indigo; manuf rubber substitutes; with amorphous phosphorus as ignition surface for matches; pyrotechny; manuf pigments; in analytical chemistry.