Dipotassium phosphate
| Names | |
|---|---|
| IUPAC name Potassium hydrogen phosphate | |
| Other names Potassium monohydrogen phosphate Phosphoric acid dipotassium salt Potassium phosphate dibasic | |
| Identifiers | |
| 
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| 3D model (JSmol) | |
| ChEBI | |
| ChEMBL | |
| ChemSpider | |
| ECHA InfoCard | 100.028.940 | 
| EC Number | 
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| E number | E340(ii) (antioxidants, ...) | 
| PubChem CID | |
| UNII | 
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| CompTox Dashboard (EPA) | |
| 
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| 
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| Properties | |
| K2HPO4 | |
| Molar mass | 174.2 g/mol | 
| Appearance | white powder deliquescent | 
| Odor | odorless | 
| Density | 2.44 g/cm3 | 
| Melting point | > 465 °C (869 °F; 738 K) decomposes | 
| 149.25 g/100 mL (20 °C) | |
| Solubility | slightly soluble in alcohol | 
| Acidity (pKa) | 12.4 | 
| Basicity (pKb) | 6.8 | 
| Hazards | |
| NFPA 704 (fire diamond) | |
| Flash point | Non-flammable | 
| Related compounds | |
| Other cations | Disodium phosphate Diammonium phosphate | 
| Related compounds | Monopotassium phosphate Tripotassium phosphate | 
| Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references | |
Dipotassium phosphate (also dipotassium hydrogen orthophosphate or potassium phosphate dibasic) is the inorganic compound with the formula K2HPO4.(H2O)x (x = 0, 3, 6). Together with monopotassium phosphate (KH2PO4.(H2O)x), it is often used as a fertilizer, food additive, and buffering agent. It is a white or colorless solid that is soluble in water.
It is produced commercially by partial neutralization of phosphoric acid with two equivalents of potassium chloride:
- H3PO4 + 2 KCl → K2HPO4 + 2 HCl