Copper(II) sulfate

Copper(II) sulfate is the chalcanthite. Archaic names for copper(II) sulfate are "blue vitriol" and "bluestone".^[1]

Preparation

Since it is available commercially, copper sulfate is usually purchased, not prepared in the laboratory. It can be made by the action of sulfur trioxide (SO₃). When heated in an open flame the crystals are dehydrated and turn grayish-white.^[2]

Uses

As an herbicide, fungicide, pesticide

Copper sulfate pentahydrate is a fungicide. Mixed with herbicide is not agricultural, but instead for control of invasive exotic aquatic plants and the roots of other invasive plants near various pipes that contain water. A dilute solution of copper sulfate is used to treat aquarium fish of various parasitic infections,^[4] and is also used to remove snails from aquariums. However, as the copper ions are also highly toxic to the fish, care must be taken with the dosage. Most species of algae can be controlled with very low concentrations of copper sulfate. Copper sulfate inhibits growth of bacteria such as E. coli.

Analytical reagent

Several chemical tests utilize copper sulfate. It is used in Biuret reagent to test for proteins.

Copper sulfate is also used to test blood for anemia. The blood is tested by dropping it into a solution of copper sulfate of known specific gravity — blood which contains sufficient hemoglobin sinks rapidly due to its density, whereas blood which does not floats or sinks slowly.^[5]

In a barium.

Organic synthesis

Copper sulfate is employed in potassium permanganate to give an oxidant for the conversion of primary alcohols.^[8]

Chemistry education

Copper sulphate is a commonly included chemical in children's pentahydrate form, which is blue, is heated, turning the copper sulfate into the anhydrous form which is white, while the water that was present in the pentahydrate form evaporates. When water is then added to the anhydrous compound, it turns back into the pentahydrate form, regaining its blue colour.

In an illustration of a "single metal replacement reaction," iron is submerged in a solution of copper sulfate. Upon standing, iron dissolves and copper precipitates.

Fe + CuSO₄ → FeSO₄ + Cu

The copper can also be electroplated to the iron.

Other uses

Other applications include hair textiles, an ingredient in baby formula milk, and in pyrotechnics as a green colorant.^[9]

References

1. ^ Copper(II) sulfate MSDS. Oxford University. Retrieved on 2007-12-31.
2. ^ Holleman, A. F.; Wiberg, E. Inorganic Chemistry Academic Press: San Diego, 2001. ISBN 0-12-352651-5.
3. ^ Uses of Copper Compounds: Copper Sulphate's Role in Agriculture. Copper.org. Retrieved on 2007-12-31.
4. ^ All About Copper Sulfate. National Fish Pharmaceuticals. Retrieved on 2007-12-31.
5. ^ Barbara H. Estridge, Anna P. Reynolds, Norma J. Walters (2000). Basic Medical Laboratory Techniques. Thomson Delmar Learning, 166. ISBN 0766812065. 
6. ^ Hoffman, R. V. "Copper(II) Sulfate" Encyclopedia of Reagents for Organic Synthesis, 2001 John Wiley & Sons. DOI: 10.1002/047084289X.rc247
7. ^ Hulce, M. Mallomo, J. P.; Frye, L. L.; Kogan, T. P.; Posner, G. H. (1990). "(S)-( + )-2-(p-Toluenesulfinyl)-2-Cyclopentanone: Precursor for Enantioselective Synthesis of 3-Substituted Cyclopentanones". Org. Synth.; Coll. Vol. 7: 495. 
8. ^ Jefford, C. W.; Li, Y.; Wang, Y.. "A Selective, Heterogeneous Oxidation using a Mixture of Potassium Permanganate and Cupric Sulfate: (3aS,7aR)-Hexahydro-(3S,6R)-Dimethyl-2(3H)-Benzofuranone". Org. Synth.; Coll. Vol. 9: 462. 
9. ^ Uses of Copper Compounds: Table A - Uses of Copper Sulphate. Copper.org. Retrieved on 2007-12-31.