| Names | |
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Preferred IUPAC name
Lead tetroxide
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| Identifiers | |
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1314-41-6 |
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| 3D model (Jmol) | Interactive image |
| ChemSpider |
21169908 |
| ECHA InfoCard | 100.013.851 |
| EC Number | 215-235-6 |
| PubChem | 16685188 |
| UN number | 1479 |
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| Properties | |
| Pb 3O 4 |
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| 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) |
| Structure | |
| Tetragonal, tP28 | |
| P42/mbc, No. 135 | |
| Hazards | |
| GHS pictograms |
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| GHS signal word | DANGER |
| H272, H302, H332, H360, H373, H410 | |
| P201, P220, P273, P308+313, P501 | |
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EU classification (DSD)
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| R-phrases | R61, R20/22, R33, R50/53, R62 |
| S-phrases | S53, S45, S60, S61 |
| NFPA 704 | |
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Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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| Infobox references | |
Lead(II,IV) oxide, also called minium, red lead or triplumbic tetroxide, is a bright red or orange crystalline or amorphous pigment. Chemically, red lead is Pb3O4, or 2 PbO·PbO2. Pb3O4,is [2PbO].[PbO2] or Lead(II,IV) oxide. It is used in the manufacture of batteries, lead glass and rust-proof primer paints.
Lead(II,IV) oxide has a tetragonal crystal structure at room temperature, which transforms to an orthorhombic (Pearson symbol oP28, Space group = Pbam, No 55) form at temperature 170 K. This phase transition only changes the symmetry of the crystal and slightly modifies the interatomic distances and angles.
Unit cell of tetragonal Pb3O4 (Key: Pb O)
Part of tetragonal red lead's crystal structure
Lead(II,IV) oxide is prepared by calcination of lead(II) oxide (also called litharge) in air at about 450 to 480 °C:
The resulting material is contaminated with lead(II) oxide. If a pure compound is desired, PbO can be removed by a potassium hydroxide solution:
Another method of preparation relies on annealing of lead carbonate (cerussite) in air: