Copper arsenate (Cu
3(AsO
4)
2·4H
2O, or Cu
5H
2(AsO
4)
4·2H
2O), also called copper orthoarsenate, tricopper arsenate, cupric arsenate, or tricopper orthoarsenate, is a blue or bluish-green powder insoluble in water and alcohol and soluble in aqueous
ammonium
Ammonium is a modified form of ammonia that has an extra hydrogen atom. It is a positively charged (cationic) polyatomic ion, molecular ion with the chemical formula or . It is formed by the protonation, addition of a proton (a hydrogen nucleu ...
and dilute acids.
Uses
Copper arsenate is an
insecticide
Insecticides are pesticides used to kill insects. They include ovicides and larvicides used against insect eggs and larvae, respectively. The major use of insecticides is in agriculture, but they are also used in home and garden settings, i ...
used in agriculture. It is also used as a
herbicide
Herbicides (, ), also commonly known as weed killers, are substances used to control undesired plants, also known as weeds.EPA. February 201Pesticides Industry. Sales and Usage 2006 and 2007: Market Estimates. Summary in press releasMain page f ...
,
fungicide
Fungicides are pesticides used to kill parasitic fungi or their spores. Fungi can cause serious damage in agriculture, resulting in losses of yield and quality. Fungicides are used both in agriculture and to fight fungal infections in animals, ...
, and a
rodenticide
Rodenticides are chemicals made and sold for the purpose of killing rodents. While commonly referred to as "rat poison", rodenticides are also used to kill mice, woodchucks, chipmunks, porcupines, nutria, beavers, and voles.
Some rodenticides ...
. It is also used as a poison in
slug
Slug, or land slug, is a common name for any apparently shell-less Terrestrial mollusc, terrestrial gastropod mollusc. The word ''slug'' is also often used as part of the common name of any gastropod mollusc that has no shell, a very reduced ...
baits.
Copper arsenate can also be a misnomer for
copper arsenite, especially when meant as a
pigment
A pigment is a powder used to add or alter color or change visual appearance. Pigments are completely or nearly solubility, insoluble and reactivity (chemistry), chemically unreactive in water or another medium; in contrast, dyes are colored sub ...
.
Natural occurrences
Anhydrous copper arsenate, Cu
3(AsO
4)
2, is found in nature as the mineral lammerite. Copper arsenate tetrahydrate, Cu
3(AsO
4)
2·4H
2O, occurs naturally as the mineral rollandite.
Related compounds
Copper arsenate hydroxide or basic copper arsenate (Cu(OH)AsO
4) is a basic variant with CAS number 16102-92-4. It is found naturally as the mineral
olivenite. It is used as an insecticide, fungicide, and
miticide. Its use is banned in Thailand since 2001.
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
{{Insecticides
Arsenates
Copper(II) compounds
Inorganic insecticides
Arsenical herbicides
Rodenticides
Fungicides