Copper(II) hydroxide Identifiers Properties Hazards
IUPAC name Copper(II) hydroxide
various other names Cupric hydroxide
CAS number 20427-59-2
molecule formula Cu(OH)2
Molar mass 97.561 g/mol
Appearance Blue or blue-green solid
Density 3.37 g/cm3, solid
melting point

n/a, decomposes into CuO

Solubility in water insoluble
Solubility in ethanol insoluble
main hazards Skin, Eye, & respiratory Irritant
NFPA 704
R-phrases R36 R37 R38 S-phrases S26 flash point Non-flammable connected Compounds various other anions CuSO4, CuCl2, CuO, Cu(NO3)2, CuCO3 various other cations NaOH, KOH, Mg(OH)2, Ca(OH)2, Ni(OH)2, Al(OH)3 other than where noted otherwise, data are offered for products in their standard state(at 25°C, 100kPa)Infobox disclaimer and references

Copper(II) hydroxide (chemical formula Cu(OH)2) is the hydroxide the the steel copper. The typical shade of copper hydroxide is blue. Some creates of copper(II) hydroxide are marketed as "stabilized" copper hydroxide, quite most likely a mixture of copper(II) carbonate and also hydroxide. These are often greener in color.

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2 chemical Properties



Copper(II) hydroxide has been well-known to man due to the fact that copper smelting began approximately 5000 BCE return the alchemists were more than likely the very first to to produce it.<1> This was easily done by mixing solutions of lye and also blue vitriol, both chemicals which were well-known in antiquity.

It was created on an commercial scale during the 17th and 18th century for use in pigments such together blue verditer and also Bremen green.<2> these pigments were provided in ceramics and painting.<3>

chemical Properties


Copper(II) hydroxide deserve to be produced by including a small amount of sodium hydroxide to a dilute systems of copper(II) sulfate (CuSO4 · 5H2O). The precipitate created in this manner, however, often has an appreciable lot of salt hydroxide impurity and a purer product have the right to be attained if ammonium chloride is added to the equipment beforehand. Alternatively, copper hydroxide is conveniently made by electrolysis that water (containing a little electrolyte such as sodium bicarbonate). A copper anode is used, regularly made native scrap copper.

"Copper in moist air progressively acquires a dull green coating. The green material is a 1:1 mole mixture that Cu(OH)2 and also CuCO3."<4>

2Cu(s) + H2O(g) + CO2(g) + O2(g) ---> Cu(OH)2(s) + CuCO3(s)

This is the patina that forms on bronze and other copper alloy statues such together the Statue of Liberty.


Moist samples that copper(II) hydroxide progressively turn black as result of the formation of copper(II) oxide.<5> as soon as it is dry, however, copper(II) hydroxide does not decompose uneven it is heated come 185°C.<6>

Copper(II) hydroxide reacts v a equipment of ammonia to form a deep blue equipment consisting the the 2+ complicated ion, but the hydroxide is reformed as soon as the equipment is diluted with water. Copper(II) hydroxide in ammonia solution, well-known as Schweizer"s reagent, own the interesting capacity to dissolve cellulose. This property brought about it being supplied in the production of rayon, a cellulosic fiber.

Since copper(II) hydroxide is mildly amphoteric, that dissolves contempt in focused alkali, creating 2-.<7>

usage as an organic reagent

Copper(II) hydroxide has a rather dedicated role in organic synthesis. Often, once it is utilized for this purpose, the is ready in situ by mixing a dissolve copper(II) salt and also potassium hydroxide.

It is periodically used in the synthetic of aryl amines. Because that example, copper(II) hydroxide catalyzes the reaction that ethylenediamine through 1-bromoanthraquinone or 1-amino-4-bromoanthraquinone to form 1-((2-aminoethyl)amino)anthraquinone or 1-amino-4-((2-aminoethyl)amino)anthraquinone, respectively.

Copper(II) hydroxide also converts acid hydrazides come carboxylic mountain at room temperature. This is especially useful in synthesizing carboxylic acids v other delicate functional groups. The released yields are normally excellent as is the case with the manufacturing of benzoic acid and also octanoic acid.

organic occurrence

Copper(II) hydroxide is found in several various copper minerals, many notably azurite, malachite, antlerite, and also brochantite. Azurite (2CuCO3 • Cu(OH)2) and also malachite (CuCO3 • Cu(OH)2) are carbonates while antlerite (CuSO4 • 2Cu(OH)2) and also brochantite (CuSO4 • 3Cu(OH)2) room sulfates. Copper(II) hydroxide is rarely uncovered as one uncombined mineral due to the fact that it gradually reacts with carbon dioxide indigenous the setting to form a an easy copper(II) carbonate.


Copper(II) hydroxide has actually been supplied as an alternate to the Bordeaux mixture, a fungicide and nematacide.<8> Nowadays, it is disfavored since of environmental contamination problems. Copper(II) hydroxide is likewise occasionally offered as ceramic colorant.


Copper(II) hydroxide is a skin, eye and also respiratory irritant. Constantly wear safety glasses when handling copper hydroxide. In situation of call with eyes, rinse instantly with plenty of water and seek clinical advice.


Roscoe, H. E., & Schorlemmer, C. (1879). A treatise on Chemistry 2nd Ed, Vol 2, component 2. MacMillan & Co. (p 498). Paquette, Leo A. (1995). Encyclopedia the Reagents because that Organic Synthesis, 8 Volume Set. Wiley. ISBN 0-4719-3623-5.

See more: What Is 1/3 Plus 1/4 + 2 1/3, Fraction Calculator: 3 1/4 + 2 1/3

This post is licensed under the GNU cost-free Documentation License. That uses material from the Wikipedia short article "Copper(II)_hydroxide". A list of authors is obtainable in Wikipedia.