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blue copperas

noun, Chemistry

blue vitriol

noun, Chemistry, Mineralogy
1.
a salt, copper sulfate, CuSO 4 ⋅5H 2 O, occurring naturally as large transparent, deep-blue triclinic crystals, appearing in its anhydrous state as a white powder: used chiefly as a mordant, insecticide, fungicide, and in engraving.
Also called blue copperas, chalcanthite, cupric sulfate.
Origin of blue vitriol
1760-1770
1760-70
Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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British Dictionary definitions for blue copperas

blue vitriol

noun
1.
the fully hydrated blue crystalline form of copper sulphate
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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blue copperas in Science
blue vitriol  
A blue, crystalline compound of copper sulfate. Blue vitriol is soluble in water, and is a very important industrial salt of copper. It is used in insecticides and germicides, in electrolytes for batteries, and in electroplating baths. Chemical formula: CuSO4·5H2O.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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