Copper Sulfate Pentahydrate

The chemical formula for Copper Sulfate Pentahydrate is CuSO₄·5H₂O. Its CAS is 7758-98-8. The highly toxic, non-combustible, odorless blue crystalline powder has a nauseating metallic taste and turns white when dehydrated. The structure of the solid pentahydrate reveals a polymeric structure wherein copper is again octahedral but bound to four water ligands. The Cu(II)(H₂O)₄ centers are interconnected by sulfate anions to form chains.

Skin contact can cause first-degree burns on short exposure, with second-degree burns from prolonged exposure. It is soluble in methanol but insoluble in ethanol. It readily forms soluble alkaline complexes at sufficiently high concentrations of amines or alkali cyanides.

According to Ullmann’s Encyclopedia of Industrial Chemistry, copper sulfate pentahydrate is most easily prepared by the reaction of basic copper (II) compound with a sulfuric acid solution. Copper metal, sulfuric acid and air are the most common starting materials for the production of the inorganic compound.

Copper sulfate pentahydrate is primarily used as a fungicide. However, some fungi are capable of adapting to elevated levels of copper ions.