Difference between revisions of "Copper arsenite"

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Latest revision as of 10:26, 8 December 2022

Description

A light yellowish-green toxic powder known as the pigment Scheele's green. Copper arsenite was discovered in Sweden 1775 by C.W. Scheele, a German chemist, but he did not publish the recipe until 1778. Scheele's green was never widely used as a paint pigment because it was toxic and discolored in the presence of acid or sulfur fumes. Currently, it is used as a rodenticide, Insecticide, Fungicide, and wood preservative.

Raman (UCL)

ScheelesUCL.jpg

Synonyms and Related Terms

Scheele's green; cupric arsenite; Pigment Green 22; CI 77412; mineral green; ash green; cupric acid orthoarsenite; copper orthoarsenite

Risks

  • Extremely toxic by ingestion, inhalation and skin absorption.
  • Human carcinogen.
  • May produce toxic arsenic fumes when decomposed by fungi.
  • NIH: Safety sheet

Physical and Chemical Properties

Soluble in mineral acids, ethanol, ammonium hydroxide. Insoluble in water. Decomposes in alkalis. Darkens in the presence of sulfur or lead compounds.

Composition CuHAsO3
CAS 10290-12-7
Molecular Weight mol. wt. = 187.5
Refractive Index 1.55 - 1.75

Resources and Citations

  • D.A.Scott, Copper and Bronze in Art: Corrosion, Colorants, Conservation, Getty Publications, Los Angeles, 2002.
  • Thomas B. Brill, Light Its Interaction with Art and Antiquities, Plenum Press, New York City, 1980
  • The Dictionary of Art, Grove's Dictionaries Inc., New York, 1996 Comment: "Pigments"
  • Richard S. Lewis, Hawley's Condensed Chemical Dictionary, Van Nostrand Reinhold, New York, 10th ed., 1993
  • Random House, Webster's Encyclopedic Unabridged Dictionary of the English Language, Grammercy Book, New York, 1997