Lead(II) bromide

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Lead(II) bromide
Lead(II) bromide
Identifiers
CAS number 10031-22-8 YesY
PubChem 24831
Properties
Molecular formula PbBr2
Molar mass 367.01 g/mol
Appearance white powder
Density 6.66 g/cm3 [1]
Melting point 373 °C
Boiling point 916 °C (vaporizes)
Solubility in water 0.455 g/100 mL (0 °C)
0.973 g/100 mL (20 °C)[2]
4.41 g/100 mL (100 °C)
Solubility product, Ksp 1.86 x 10-5 (20 °C)
Solubility insoluble in alcohol;
soluble in ammonia, alkali, KBr, NaBr
Hazards
EU Index 082-001-00-6
EU classification Repr. Cat. 1/3
Harmful (Xn)
Dangerous for the environment (N)
R-phrases R61, R20/22, R33, R62, R50/53
S-phrases S53, S45, S60, S61
NFPA 704
Flammability code 0: Will not burn. E.g., water Health code 3: Short exposure could cause serious temporary or residual injury. E.g., chlorine gas Reactivity code 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g., liquid nitrogen Special hazards (white): no codeNFPA 704 four-colored diamond
Related compounds
Other anions Lead(II) fluoride,
Lead(II) chloride,
Lead(II) iodide
Other cations Thallium(I) bromide,
Tin(II) bromide
Bismuth bromide
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
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Infobox references

Lead(II) bromide is the inorganic compound with the formula PbBr2. It is a white powder. It is produced in the burning of typical leaded gasolines.[3]

Preparation and properties[edit]

It is typically prepared from treating solutions of lead salts (e.g., (lead(II) nitrate) with bromide salts. This process exploits its low solubility in water - only 0.455 g dissolves in 100 g of water at 0°C. It is about ten times more soluble in boiling water.[4]

Lead bromide was prevalent in the environment as the result of the use of leaded gasoline. Tetraethyl lead was once widely used to improve the combustion properties of gasoline. To prevent the resulting lead oxides from fouling the engine, gasoline was treated with an organobromine compound that converted lead oxides into the more volatile lead bromide, which was then exhausted from the engine into the environment.[3]

Safety[edit]

Like other compounds containing lead, lead dibromide is categorized as probably carcinogenic to humans (Category 2A), by the International Agency for Research on Cancer (IARC). Its release into the environment as a product of leaded gasoline was highly controversial.

References[edit]

  1. ^ Lide, David R., ed. (2006). CRC Handbook of Chemistry and Physics (87th ed.). Boca Raton, FL: CRC Press. ISBN 0-8493-0487-3. 
  2. ^ NIST-data review 1980
  3. ^ a b Michael J. Dagani, Henry J. Barda, Theodore J. Benya, David C. Sanders "Bromine Compounds" in Ullmann's Encyclopedia of Industrial Chemistry" Wiley-VCH, Weinheim, 2000.doi:10.1002/14356007.a04_405
  4. ^ Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. ISBN 0080379419.