What does arsenate mean?
An arsenate is a chemical compound containing the AsO₄³⁻ ion, formed when arsenic acid reacts with a metal or organic base; it is the arsenic analogue of a phosphate or sulfate salt. Arsenates are typically crystalline solids, and most are highly toxic because arsenic interferes with essential biochemical processes. They occur naturally in certain minerals, where they are studied by mineralogists as a distinct class of ore-forming compounds. Historically, arsenates such as lead arsenate and calcium arsenate were widely used as insecticides and herbicides before safer alternatives were developed, leaving persistent contamination in some agricultural soils. The term belongs mainly to the vocabulary of chemistry, geology, and environmental science rather than everyday conversation, but it remains important in discussions of water quality, industrial pollution, and food safety, where detecting even trace levels of arsenate matters for public health.
nounA salt or ester of arsenic acid, containing the AsO₄³⁻ ion. Arsenates are typically toxic crystalline compounds found in some minerals and formerly used in pesticides.
- A salt or ester of arsenic acid containing the pentavalent AsO₄³⁻ anion.
- Any of various minerals composed essentially of arsenates.
"The old orchard soil still contained residues of lead arsenate from decades of pesticide spraying."
"Calcium arsenate was once widely sprayed on cotton fields to control the boll weevil."
"The mineral sample was identified as an iron arsenate under the polarizing microscope."
Regular plural; commonly used when referring to multiple arsenate compounds or mineral species.
"Several copper arsenates are prized by collectors for their vivid green and blue colours."
In 2010, NASA researchers claimed a bacterium could substitute arsenate for phosphate in its DNA — one of the most debated findings in modern biology.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of arsenate
Arsenate derives from arsenic, which entered English via Latin arsenicum and Greek arsenikon (or zarunik in Syriac), originally referring to the yellow pigment orpiment. The suffix -ate marks salts derived from acids whose names end in -ic, following the systematic nomenclature codified by European chemists in the late eighteenth and early nineteenth centuries. Cognate terms include arsine, the hydride of arsenic, and the adjective arsenious.
How arsenate is actually used
Arsenate is chiefly a technical term used in chemistry, mineralogy, environmental science, and discussions of toxicology and agricultural history. It carries strongly negative connotations because most arsenates are poisonous; it is rarely encountered in everyday speech outside these specialist contexts.
Easily confused with arsenate
An arsenite contains the trivalent AsO₃³⁻ ion derived from arsenious acid, whereas an arsenate contains the pentavalent AsO₄³⁻ ion derived from arsenic acid.