Article · Wikipedia archive · Last revised Jul 21, 2026

Copper(II) citrate

Copper(II) citrate is the copper(II) salt of citric acid that occurs in several hydration states. Commercial material is commonly a blue-green solid and is used as a source of copper in industrial, agricultural and some supplement applications.

Last revised
Jul 21, 2026
Read time
≈ 1 min
Length
321 w
Citations
12
Source
Wikipedia ↗
Copper(II) citrate
source ↗
Skeletal formula of the compound
source ↗
Anhydrous copper(II) citrate
Names
IUPAC name
copper(II) 2-oxidopropane-1,2,3-tricarboxylate
Other names
cupric citrate; dicopper citrate
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.169.194
EC Number
  • 212-752-9
UNII
  • InChI=1S/C6H7O7.2Cu/c7-3(8)1-6(13,5(11)12)2-4(9)10;;/h1-2H2,(H,7,8)(H,9,10)(H,11,12);;/q-1;2*+2/p-3
    Key: FWBOFUGDKHMVPI-UHFFFAOYSA-K
  • hemipentahydrate: InChI=1S/2C6H7O7.4Cu.5H2O/c2*7-3(8)1-6(13,5(11)12)2-4(9)10;;;;;;;;;/h2*1-2H2,(H,7,8)(H,9,10)(H,11,12);;;;;5*1H2/q2*-1;4*+2;;;;;/p-6
    Key: NBHBWRHMKGDJMS-UHFFFAOYSA-H
  • C(C(=O)[O-])C(CC(=O)[O-])(C(=O)[O-])[O-].[Cu+2].[Cu+2]
  • hemipentahydrate: C(C(=O)[O-])C(CC(=O)[O-])(C(=O)[O-])[O-].C(C(=O)[O-])C(CC(=O)[O-])(C(=O)[O-])[O-].O.O.O.O.O.[Cu+2].[Cu+2].[Cu+2].[Cu+2]
Properties
C6H4Cu2O7 (anhydrous); C6H4Cu2O7·2.5H2O (hemipentahydrate)1
Molar mass 315.18 g·mol−1 (anhydrous); 360.22 g·mol−1 (2.5-hydrate)2
Appearance blue-green solid2
Density 1.667 g·cm−32
slightly soluble in water; more soluble in dilute acids and in aqueous ammonia3
Hazards
GHS labelling:[1]
GHS07: Exclamation markGHS09: Environmental hazard
Warning
H302, H410
P264, P270, P273, P301+P317, P330, P391, P501
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Copper(II) citrate is the copper(II) salt of citric acid that occurs in several hydration states. Commercial material is commonly a blue-green solid and is used as a source of copper in industrial, agricultural and some supplement applications.12

Properties

The anhydrous powder is blue while the hydrate is a light green.2

Preparation

Copper(II) citrate can be prepared by reacting a soluble copper(II) salt such as copper(II) sulfate with trisodium citrate or tripotassium citrate; different hydrate stoichiometries may be isolated depending on conditions.4

Uses

Copper(II) citrate is used as a copper source in some agricultural micronutrient formulations and in proprietary supplement formulations. It is also used as a reagent and copper source in industrial and research contexts.56

References

References

  1. "Cupric citrate". PubChem. Retrieved 2025-11-17.
  2. "Copper(II) Citrate 2.5-Water product data". FUJIFILM Wako. Retrieved 2025-11-17.
  3. "Copper citrate - supplier data and solubility notes". Lohmann Minerals. Retrieved 2025-11-17.
  4. "Cupric citrate — product information". Sigma-Aldrich / Merck. Retrieved 2025-11-17.
  5. "Copper fungicides for organic and conventional disease management in vegetables". Cornell University. Retrieved 2025-11-17.
  6. "Copper supplements: product example". Pure Encapsulations (product page). Retrieved 2025-11-17.