Strontium phosphate
Chemical compound
From Wikipedia, the free encyclopedia
Strontium phosphate is the phosphate salt of strontium, with the molecular formula Sr3(PO4)2. It is a white solid insoluble in water.[5]
| Identifiers | |
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3D model (JSmol) |
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| ChemSpider | |
| ECHA InfoCard | 100.028.369 |
| EC Number |
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PubChem CID |
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| UNII | |
CompTox Dashboard (EPA) |
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| Properties | |
| Sr3(PO4)2 | |
| Molar mass | 452.8 g/mol |
| Appearance | White solid |
| Density | 4.53 g/cm3 |
| Melting point | 1,620 °C (2,950 °F; 1,890 K)[1] |
| Insoluble[2][3] | |
| Structure[4] | |
| Rhombohedral | |
| R3m | |
a = 5.39 Å, c = 19.78 Å | |
Lattice volume (V) |
497.8 Å3 |
| Related compounds | |
Other anions |
Strontium sulfate |
Other cations |
Tricalcium phosphate Barium phosphate |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Preparation and properties
Strontium phosphate is commonly produced by the reaction of soluble strontium compounds, such as strontium nitrate, and a phosphate source, such as phosphoric acid or tripotassium phosphate, in water, resulting in a white precipitate of the tetrahydrate:[6][7]
- 3 Sr(NO3)2 + 2 K3PO4 + 4 H2O → Sr3(PO4)2·4H2O↓ + 6 KNO3
Under water, the tetrahydrate slowly hydrolyses to strontium hydroxyapatite (Sr10(PO4)6(OH)2). The tetrahydrate decomposes to the anhydrous form when heated to 900 °C.[6][7]
The anhydrous form can be produced without the presence of water, to avoid hydrolysis, by the heating of ammonium dihydrogen phosphate and strontium carbonate at 1030 °C and 30 MPa of pressure.[4][8]