Cadmium phosphate

Not to be confused with Cadmium phosphide.

Cadmium phosphate is an inorganic phosphate salt of cadmium, with the molecular formula Cd₃(PO₄)₂.^[2] It is a white, water-insoluble solid.

Cadmium phosphate

Names
IUPAC name Cadmium phosphate
Identifiers
CAS Number	13477-17-3
3D model (JSmol)	Interactive image
ChemSpider	24274
ECHA InfoCard	100.033.408
EC Number	236-764-9
PubChem CID	26060
CompTox Dashboard (EPA)	DTXSID60889611
InChI InChI=1S/3Cd.2H3O4P/c;;;2*1-5(2,3)4/h;;;2*(H3,1,2,3,4)/q3*+2;;/p-6 Key: NRGIRRZWCDKDMV-UHFFFAOYSA-H
SMILES [O-]P(=O)([O-])[O-].[O-]P(=O)([O-])[O-].[Cd+2].[Cd+2].[Cd+2]
Properties
Chemical formula	Cd3(PO4)2
Molar mass	527.18 g/mol
Appearance	White solid[1]
Density	5.17 g/cm3[1]
Melting point	1,500 °C (2,730 °F; 1,770 K)
Solubility in water	Insoluble
Solubility product (Ksp)	2.53 × 10–33
Hazards
GHS labelling:
Pictograms
Signal word	Danger
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Synthesis

Tricadmium phosphate can be prepared by the reaction of cadmium chloride with diammonium phosphate at 800 °C:^[3]

3 CdCl₂ + 2 (NH₄)₂HPO₄ → Cd₃(PO₄)₂ + 4 NH₄Cl + 2 HCl

The precipitation of aqueous cadmium ions with soluble phosphate sources, such as trisodium phosphate and phosphoric acid, does not produce Cd₃(PO₄)₂, but instead produces a hydrate of cadmium with the formula Cd₅H₂(PO₄)₄·4H₂O. When this compound is heated, it yields a mixture of cadmium phosphate and cadmium pyrophosphate, Cd₂P₂O₇.^[4]

Uses

Cadmium phosphate can be used as a fertilizer to provide phosphorus to crops for their growth.^[2]

See also

• Cadmium phosphide