Lead(II) iodide

Chembox new
Name = "Lead(II) iodide"
ImageFile = Lead-diiodide-3D-polyhedra.png ImageSize = 200px
ImageName = Lead(II) iodide
OtherNames = Lead diiodide, lead iodide
Section1 = Chembox Identifiers
CASNo = 10101-63-0
Section2 = Chembox Properties
Formula = PbI₂
MolarMass = 461.05 g/mol
Density = 6.16 g/cm³
Solvent = other solvents
SolubleOther = 1 g in 1350 mL cold water
1 g in 230 mL hot water
MeltingPt = 403 °C
BoilingPt = 872 °C

Lead (II) iodide (PbI₂) is a toxic, yellowish solid. It displays a range of colors with varying temperature from bright yellow at room temperature to brick red. On cooling, its color returns to yellow. In its crystalline form it is used as a detector material for high energy photons including x-rays and gamma rays. It is also known as plumbous iodide, derived from the Latin name for lead "plumbum".

Lead iodide is toxic due to its lead content.

In the nineteenth century it was used as an artists' pigment under the name "Iodine Yellow", but it was too unstable to be useful. Salter, Thomas W., "Field’s Chromatography: or Treatise on Colours and Pigments as Used by Artists By George Field. An entirely new and practical edition revised, rewritten and brought down to the present time", 1869]

Lead iodide is formed via precipitation by mixing lead(II) nitrate and potassium iodide:

:Pb(NO₃)₂ (aq) + 2KI (aq) → PbI₂ (s) + 2KNO₃ (aq)

The resultant bright yellow solids are easily recrystallized in hot water to yield brilliant yellow crystals.

References

External links

* [http://www.atsdr.cdc.gov/HEC/CSEM/lead/ Case Studies in Environmental Medicine (CSEM): Lead Toxicity]
* [http://www.atsdr.cdc.gov/tfacts13.html ToxFAQs™: Lead]
* [http://www.npi.gov.au/database/substance-info/profiles/50.html National Pollutant Inventory - Lead and Lead Compounds Fact Sheet]