Copper arsenate is an inorganic compound with the chemical formula Cu3(AsO4)2·nH2O (n=0,4). It is a blue or bluish-green solid, forming monoclinic crystals.

Occurrence

Anhydrous copper arsenate (Cu3(AsO4)2) is found in nature as the mineral lammerite. The tetrahydrate (Cu3(AsO4)2·4H2O) occurs naturally as the mineral rollandite.

Preparation

Copper arsenate can be prepared by reacting disodium hydrogen arsenate and copper(II) chloride in aqueous solution.

Uses

Copper arsenate is an insecticide used in agriculture. It is also used as a herbicide, fungicide, and a rodenticide. It is also used as a poison in slug baits.

Related compounds

Basic copper arsenates with the formulas Cu2(OH)AsO4 and Cu3(AsO4)(OH)3 have been observed. The former is found naturally as the mineral olivenite.

See also

• Calcium arsenate

• Chromated copper arsenate

• Lead arsenate

• Paris green (copper acetoarsenite)

• Scheele's green (copper arsenite)

References

External links

• National Pollutant Inventory - Copper and compounds fact sheet