Dimagnesium phosphate

This article is about Dimagnesium phosphate. For other uses, see magnesium phosphate.

Dimagnesium phosphate

Names
Other names Magnesium hydrogen phosphate; Magnesium phosphate dibasic
Identifiers
CAS Number	7757-86-0 Y 7782-75-4 (trihydrate) Y
3D model (JSmol)	Interactive image
ChemSpider	110477 N
EC Number	231-823-5
PubChem CID	123955
UNII	A1Y870209Z Y HF539G9L3Q (trihydrate) Y
InChI InChI=1S/Mg.H3O4P/c;1-5(2,3)4/h;(H3,1,2,3,4)/q+2;/p-2 N Key: MHJAJDCZWVHCPF-UHFFFAOYSA-L N
SMILES O=P([O-])(O)[O-].[Mg+2]
Properties
Chemical formula	HMgO4P
Molar mass	120.283 g·mol−1
Density	2.13 g/cm3 trihydrate
Hazards
NFPA 704 (fire diamond)	<imagemap> File:NFPA 704.svg|80px|alt=NFPA 704 four-colored diamond poly 150 150 300 300 150 450 0 300 Health 0: Exposure under fire conditions would offer no hazard beyond that of ordinary combustible material. E.g. sodium chloride poly 300 0 450 150 300 300 150 150 Flammability 0: Will not burn. E.g. water poly 450 150 600 300 450 450 300 300 Instability 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogen poly 300 300 450 450 300 600 150 450 Special hazards (white): no code desc none </imagemap> 0 0 0
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is YN ?) Infobox references

Dimagnesium phosphate is a compound with formula MgHPO₄. It is a Mg²⁺ salt of monohydrogen phosphate. The trihydrate is well known, occurring as a mineral.

It can be formed by reaction of stoichiometric quantities of magnesium oxide with phosphoric acid.

MgO + H₃PO₄ → MgHPO₄ + H₂O

Dissolving monomagnesium phosphate in water, forms phosphoric acid and depositing a solid precipitate of dimagnesium phosphate trihydrate:

Mg(H₂PO₄)₂ + 3 H₂O → Mg(HPO₄)^.3H₂O + H₃PO₄

The compound is used as a nutritional supplement, especially for infants and athletes. Its E number is E343.

See also

• Magnesium phosphate