Lead(II) hydroxide

Last updated
Lead(II) hydroxide
Names
IUPAC name
Lead(II) hydroxide
Other names
  • Lead hydroxide
  • Plumbous hydroxide
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.039.358 OOjs UI icon edit-ltr-progressive.svg
EC Number
  • 243-310-3
PubChem CID
  • InChI=1S/2H2O.Pb/h2*1H2;/q;;+2/p-2 Yes check.svgY
    Key: VNZYIVBHUDKWEO-UHFFFAOYSA-L Yes check.svgY
  • InChI=1/2H2O.Pb/h2*1H2;/q;;+2/p-2
    Key: VNZYIVBHUDKWEO-NUQVWONBAE
  • [OH-].[OH-].[Pb+2]
Properties
Pb(OH)2
Molar mass 241.2 g·mol−1
0.0155 g/(100 mL) (20 °C) [1]
10−19.85 to 10−14.9 [2]
Hazards
GHS labelling:
GHS-pictogram-skull.svg GHS-pictogram-exclam.svg GHS-pictogram-pollu.svg
Danger
H302, H332, H351, H360, H373, H410
NFPA 704 (fire diamond)
NFPA 704.svgHealth 2: Intense or continued but not chronic exposure could cause temporary incapacitation or possible residual injury. E.g. chloroformFlammability 0: Will not burn. E.g. waterInstability 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogenSpecial hazards (white): no code
2
0
0
Related compounds
Other cations
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
X mark.svgN  verify  (what is  Yes check.svgYX mark.svgN ?)

Lead(II) hydroxide is an inorganic compound with the formula Pb(OH)2. The material has not been isolated but its existence has been inferred as an ill-defined component of solutions of Pb(II). [3] "Lead does not appear to form a simple hydroxide, Pb(OH)2," however. [4] Instead it forms oxides and oxy-hydroxides.

Contents

Preparation

Addition of hydroxide to a solution of a lead(II) salt, 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 or Pb6O4(OH)4. [5] This material is a cluster compound, consisting of an octahedron of Pb centers, each face of which is capped by an oxide or a hydroxide. The structure is reminiscent of the Mo6S8 subunit of the Chevrel phases. [6]

Reactions

In aqueous 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, it becomes somewhat weak acid, and it forms Pb(OH)+, Pb(OH)2(aqueous), Pb(OH)3, and other species, including several polynuclear species, e.g., Pb4(OH)4+4, Pb3(OH)2+4, Pb6O(OH)4+6. [5] Upon heating to decomposition temperatures, it forms lead oxide (PbO) in the yellow form, litharge.

History

The name lead hydrate has sometimes been used in the past but it is unclear whether this refers to Pb(OH)2 or PbO·xH2O. [7] [8] In 1964 it was believed that such a simple compound did not exist, as lead basic carbonate (2PbCO3·Pb(OH)2) or lead(II) oxide (PbO) was encountered where lead hydroxide was expected. [9] This has been a subject of considerable confusion in the past. However, subsequent research has demonstrated that lead(II) hydroxide does indeed exist as one of a series of lead hydroxides. [3]

References

  1. Handbook of Chemistry and Physics, 1st edition, 2000, CRC Press ISBN   0-8493-0740-6
  2. Internal Corrosion of Water Distribution Systems (2nd ed.). American Water Works Association. 1996. p. 178. ISBN   978-1-61300-170-7.
  3. 1 2 W. Nimal Perera, Glenn Hefter, and Pal M. Sipos (2001). "An Investigation of the Lead(II)−Hydroxide System". Inorganic Chemistry. 40 (16): 3974–3978. doi:10.1021/ic001415o. PMID   11466056.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  4. Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. p. 387. ISBN   978-0-08-037941-8.
  5. 1 2 Von Egon Wiberg, Nils Wiberg, Arnold Frederick Holleman, "Inorganic Chemistry", Academic Press, 2001 (Google books).
  6. R. A. Howie; W. Moser (1968). "Structure of Tin(II) "Hydroxide" and Lead(II) "Hydroxide". Nature. 219 (5152): 372–373. Bibcode:1968Natur.219..372H. doi:10.1038/219372a0. S2CID   45007541.
  7. "Process of treating lead hydrate produced by electrolysis".
  8. "Process of manufacturing white lead".
  9. G. Todd and E. Parry (1964). "Character of Lead Hydroxide and Basic Lead Carbonate". Nature . 202 (4930): 386–387. Bibcode:1964Natur.202..386T. doi:10.1038/202386a0. S2CID   44941178.