Copper(II) arsenate

Not to be confused with Copper arsenite.
Copper(II) arsenate
Names
IUPAC name
Copper(II) arsenate
Other names
Copper arsenate
Identifiers
3D model (JSmol)
ChemSpider
UNII
  • InChI=1S/2AsH3O4.3Cu/c2*2-1(3,4)5;;;/h2*(H3,2,3,4,5);;;/q;;3*+2/p-6 checkY
    Key: RKYSWCFUYJGIQA-UHFFFAOYSA-H checkY
  • InChI=1/2AsH3O4.3Cu/c2*2-1(3,4)5;;;/h2*(H3,2,3,4,5);;;/q;;3*+2/p-6
    Key: RKYSWCFUYJGIQA-CYFPFDDLAM
  • [Cu+2].[Cu+2].[Cu+2].[O-][As]([O-])(=O)[O-].[O-][As]([O-])([O-])=O
Properties
Cu3(AsO4)2
Molar mass 468.48 g/mol
Appearance blue or bluish green powder
Density 5.2 g/cm3
Melting point 1,100 °C (2,010 °F; 1,370 K)
insoluble
7.95×10−36[1]
Solubility soluble in ammonia, dilute acids
Hazards
NIOSH (US health exposure limits):
PEL (Permissible)
 TWA 1 mg/m3 (as Cu)[2]
REL (Recommended)
 TWA 1 mg/m3 (as Cu)[2]
IDLH (Immediate danger)
 TWA 100 mg/m3 (as Cu)[2]
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
checkY verify (what is checkY☒N ?)

Copper arsenate (Cu3(AsO4)2·4H2O, or Cu5H2(AsO4)4·2H2O), 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 and dilute acids. Its CAS number is 7778-41-8 or 10103-61-4.

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.

Copper arsenate can also be a misnomer for copper arsenite, especially when meant as a pigment.

Natural occurrences

Anhydrous copper arsenate, Cu3(AsO4)2, is found in nature as the mineral lammerite.[3] Copper arsenate tetrahydrate, Cu3(AsO4)2·4H2O, occurs naturally as the mineral rollandite.[4]

Copper arsenate hydroxide or basic copper arsenate (Cu(OH)AsO4) 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.[5]

See also

References

  1. ^ John Rumble (June 18, 2018). CRC Handbook of Chemistry and Physics (99 ed.). CRC Press. pp. 5–188. ISBN 978-1138561632.
  2. ^ a b c NIOSH Pocket Guide to Chemical Hazards. "#0150". National Institute for Occupational Safety and Health (NIOSH).
  3. ^ Hawthorne, F. C. (1986). "Lammerite, Cu3(AsO4)2, a modulated close-packed structure" (PDF). American Mineralogist. 71: 206–209.
  4. ^ Sarp, H.; Černý, R. (2000). "Rollandite, Cu3(AsO4)2·4H2O, a new mineral". Eur. J. Mineral. 12: 1045–1050. doi:10.1127/0935-1221/2000/0012-1045.
  5. ^ "Banned pesticides (Sorted by common name)". Archived from the original on 2005-11-22. Retrieved 2006-01-14.
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