Dicalcium phosphate

Dicalcium phosphate
IUPAC name Calcium hydrogenphosphate
Other names Calcium monohydrogen phosphate Phosphoric acid, calcium salt (1:1)
Identifiers
CAS number	7757-93-9 Y,  7789-77-7 (dihydrate)
PubChem	104805
ChemSpider	10605753 Y
UNII	L11K75P92J Y
Jmol-3D images	Image 1
SMILES [Ca+2].[Ca+2].[O-]P([O-])([O-])=O
InChI InChI=1S/2Ca.H3O4P/c;;1-5(2,3)4/h;;(H3,1,2,3,4)/q2*+2;/p-3 Y Key: NEFBYIFKOOEVPA-UHFFFAOYSA-K Y InChI=1/2Ca.H3O4P/c;;1-5(2,3)4/h;;(H3,1,2,3,4)/q2*+2;/p-3 Key: NEFBYIFKOOEVPA-DFZHHIFOAL
Properties
Molecular formula	CaHPO4
Molar mass	136.06 g/mol
Appearance	white powder
Density	2.929 g/cm3
Solubility in water	0.02 g/100 mL
Hazards
EU Index	Not listed
NFPA 704	0 1 0
Flash point	Non-flammable
Y phosphate (verify) (what is: Y/N?) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Dicalcium phosphate, also known as calcium monohydrogen phosphate, is a dibasic calcium phosphate. It is usually found as the dihydrate, with the chemical formula of CaHPO₄ • 2H₂O, but it can be thermally converted to the anhydrous form. It is practically insoluble in water, with a solubility of 0.02 g per 100 mL at 25 °C. It contains about 29.5 percent calcium in its anhydrous form.

Preparation

Dicalcium phosphate may be formed by the reaction of stoichiometric quantities of calcium oxide and phosphoric acid:

CaO + H₃PO₄ → CaHPO₄ + H₂O.

Uses

Dicalcium phosphate is mainly used as a dietary supplement in prepared breakfast cereals, dog treats, enriched flour, and noodle products. It is also used as a tableting agent in some pharmaceutical preparations, including some products meant to eliminate body odor. It is used in poultry feed. It is also used in some toothpastes as a tarter control agent.