Lead(II) hydroxide
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IUPAC name
Lead(II) hydroxide
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Other names
lead hydroxide
plumbous hydroxide | |
Identifiers | |
3D model (JSmol)
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ChemSpider | |
ECHA InfoCard | 100.039.358 |
CompTox Dashboard (EPA)
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Properties | |
Pb(OH)2 | |
Molar mass | 241.21 g/mol |
Appearance | white amorphous powder |
Density | 7.41 g/cm3 [1] |
Melting point | 135 °C (decomp) |
1.55 g/100 mL (20 °C) | |
Solubility product (Ksp)
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1.42 x 10-20 |
Solubility | soluble in dilute acid and alkalis; insoluble in acetone and acetic acid |
Hazards | |
NFPA 704 (fire diamond) | |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Lead(II) hydroxide, Pb(OH)2, is a hydroxide of lead, with lead in oxidation state +2. Although it appears a fundamentally simple compound, it is doubtful if lead hydroxide is stable as a solid phase.[2] Lead basic carbonate (PbCO3·2Pb(OH)2) or lead(II) oxide (PbO) is encountered in practice where lead hydroxide is expected. This has been a subject of considerable confusion in the past.
When an alkali hydroxide is added to a solution of a lead(II) salt, then a hydrated lead oxide PbO·xH2O (with x < 1) is obtained. Careful hydrolysis of lead(II) acetate solution yields a crystalline product with a formula 6PbO·2H2O = Pb6O4(OH)4.[3]
In solution, lead(II) hydroxide is a somewhat weak base, forming lead(II) ion, Pb2+, under weakly acidic conditions. This cation hydrolyzes and, under progressively increasing alkaline conditions, forms Pb(OH)+, Pb(OH)2(aqueous), Pb(OH)3−, and other species, including several polynuclear species, e.g., Pb4(OH)44+, Pb3(OH)42+, Pb6O(OH)64+.[3]
References
- ^ Pradyot Patnaik. Handbook of Inorganic Chemicals. McGraw-Hill, 2002, ISBN 0070494398
- ^ G. Todd and E. Parry (1964). "Character of Lead Hydroxide and Basic Lead Carbonate". Nature. 202 (4930): 386–387. doi:10.1038/202386a0.
- ^ a b Von Egon Wiberg, Nils Wiberg, Arnold Frederick Holleman, "Inorganic Chemistry", Academic Press, 2001 (Google books).