Lead(II) acetate

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Lead(II) acetate
IUPAC name

Lead(II) ethanoate

Systematic name

Lead(II) ethanoate

Other names

Plumbous acetate, Salt of Saturn, Sugar of Lead, lead diacetate

Identifiers
CAS number 301-04-2 YesY, 
6080-56-4 (trihydrate)
51404-69-4 (Basic)
PubChem 9317
Properties
Molecular formula Pb(C2H3O2)2
Molar mass 325.29 g/mol (anhydrous)
379.33g/mol (trihydrate)
Appearance White powder or colorless, efflorescent crystals
Odor slight acetic
Density 3.25 g/cm3 (anhydrous)
2.55 g/cm3 (trihydrate)
1.69 g/cm3 (decahydrate)
Melting point 280 °C (anhydrous)
75 °C (trihydrate)
22 °C (decahydrate)
Solubility in water 44.39 g/100 mL (20 °C)
211 g/100 mL (50 °C)[1]
Solubility anhydrous soluble in alcohol
hydrates insoluble in alcohol
Acidity (pKa) 5.5-6.5
Refractive index (nD) 1.567 (trihydrate)
Structure
Crystal structure Monoclinic (anhydrous, trihydrate)
rhombic (decahydrate)
Hazards
Main hazards Neurotoxic, Probable Human Carcinogen
NFPA 704
1
3
0
Flash point Non-flammable
 YesY (verify) (what is: YesY/N?)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
Infobox references
"Lead sugar" redirects here.

Lead(II) acetate (Pb(CH3COO)2), also known as lead acetate, lead diacetate, plumbous acetate, sugar of lead, lead sugar, salt of Saturn, and Goulard's powder, is a white crystalline chemical compound with a sweetish taste. It is made by treating lead(II) oxide with acetic acid. Like other lead compounds, it is toxic. Lead acetate is soluble in water and glycerin. With water it forms the trihydrate, Pb(CH3COO)2·3H2O, a colorless or white efflorescent monoclinic crystalline substance.

The substance is used as a reagent to make other lead compounds and as a fixative for some dyes. In low concentrations, it is the principal active ingredient in progressive types of hair coloring dyes.[citation needed] Lead(II) acetate is also used as a mordant in textile printing and dyeing, as a drier in paints and varnishes, and in preparing other lead compounds.

Uses

Sweetener

Like other lead(II) salts, lead(II) acetate has a sweet taste, which has led to its use as a sugar substitute throughout history. The ancient Romans, who had few sweeteners besides honey, would boil must (grape juice) in lead pots to produce a reduced sugar syrup called defrutum, concentrated again into sapa. This syrup was used to sweeten wine and to sweeten and preserve fruit. It is possible that lead(II) acetate or other lead compounds leaching into the syrup might have caused lead poisoning in those who consumed it.[2] Lead acetate is no longer used in the production of sweeteners in most of the world because of its recognized toxicity. Modern chemistry can easily detect it, which has all but stopped the illegal use that continued decades after legal use as a sweetener was banned.[citation needed]

Resultant deaths

Pope Clement II died in October 1047. A toxicologic examination of his remains conducted in the mid-20th century confirmed centuries-old rumors that he had been poisoned with lead sugar.[3] It is not clear if he was assassinated.

In 1787 painter Albert Christoph Dies swallowed, by accident, approximately 0.75 ounces (21 g) of lead acetate. His recovery from this poison was slow and incomplete. He lived with illnesses until his death in 1822.[citation needed]

Although the use of lead(II) acetate as a sweetener was already illegal at that time, composer Ludwig van Beethoven may have died of lead poisoning caused by wines adulterated with lead acetate.[4][5]

Mary Seacole applied lead(II) acetate, among other remedies, against an epidemic of cholera in Panama.[6][7]

Production

Lead acetate can be made by boiling elemental lead in acetic acid and hydrogen peroxide. It's also possible to create with lead carbonate or lead oxide.

Other uses

Lead(II) acetate, as well as white lead, has been used in cosmetics throughout history, though this practice has ceased in Western countries.[8] It is still used in men's hair coloring products[9] like Grecian Formula.

Lead(II) acetate paper is used to detect the poisonous gas hydrogen sulfide. The gas reacts with lead(II) acetate on the moistened test paper to form a grey precipitate of lead(II) sulfide.

Lead(II) acetate solution was a commonly used folk remedy for sore nipples.[10] In modern medicine, for a time, it was used as an astringent, in the form of Goulard's Extract.

An aqueous solution of lead(II) acetate is the byproduct of the 50/50 mixture of hydrogen peroxide and white vinegar used in the cleaning and maintenance of stainless steel firearm suppressors (silencers) and compensators. The solution is agitated by the bubbling action of the hydrogen peroxide, and the main reaction is the dissolution of lead deposits within the suppressor by the acetic acid, which forms lead acetate. Because of its high toxicity, this chemical solution must be appropriately disposed by a chemical processing facility or hazardous materials center. Alternatively, the solution may be reacted with sulfuric acid to precipitate nearly insoluble lead(II) sulfate. The solid may then be removed by mechanical filtration and is safer to dispose of than aqueous lead acetate.

It was also used in making of slow matches during the Middle Ages. It was made by mixing natural form of lead(II) oxide called litharge and vinegar.

Sugar of lead was a recommended agent added to linseed oil during heating to produce "boiled" linseed oil, the lead and heat acting to cause the oil to cure faster than raw linseed oil.[11]

Lead(II) acetate has also been used to treat poison ivy. [12]

Precautions

Lead(II) acetate, as with any other lead salts, causes lead poisoning.

See also

  • Saturn's Tree

References

  1. ↑ Pradyot Patnaik. Handbook of Inorganic Chemicals. McGraw-Hill, 2002, ISBN 0-07-049439-8
  2. ↑ Lead Poisoning and Rome
  3. ↑ Specht W and Fischer K (1959). Vergiftungsnachweis an den Resten einer 900 Jahre alten Leiche. Arch. Kriminol., 124: 61-84. [Translation:Intoxication evidence in the remains of a 900 year old corpse]
  4. ↑ Pharmazeutische Zeitung zu Beethovens wahrscheinlicher Bleivergiftung
  5. ↑ Beethoven litt unter Bleivergiftung
  6. ↑ Mary Seacole: Wonderful Adventures of Mrs. Seacole in Many Lands, Chapter IV, (1990 Oxford University Press reprint) ISBN 0-19-506672-3; (2005 Penguin 20th Century Classics reprint, ed. Sarah Salih) ISBN 0-14-043902-1
  7. ↑ Jane Robinson: Mary Seacole: The Charismatic Black Nurse who became a heroine of the Crimea, p.53. Constable 2004 (p/b. ISBN 1-84119-677-0)
  8. ↑ Gunn, Fenja. (1973). The Artificial Face: A History of Cosmetics. — as cited in Leisure Activities of an 18th Century Lady
  9. ↑ Lead Based Hair Products: Too Hazardous for Household Use - Results, Howard W. Mielke, PhD, Myiesha D. Taylor, Chris R. Gonzales, M. Kelley Smith, Pamela V. Daniels, and Ayanna V.Buckner. Journal of American Pharmaceutical Association (NS37, Jan/Feb 1997:85-89).
  10. ↑ The Project Gutenberg eBook of The American Frugal Housewife, by Lydia M. Child
  11. ↑ Andés, Louis Edgar, and Arthur Morris. Oil colours and printers' inks a practical handbook treating of linseed oil, boiled oil, paints, artists' colours, lampblack and printers' inks, black and coloured. London: Scott, Greenwood ;, 1903. 41. Print.
  12. ↑ Laboratory manual in biology. Sharpe. 1911, American Book Company. p. 351

External links

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Lead compounds
Pb(II)
Pb(II,IV)
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