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| SolubleOther = slightly soluble in [[alcohol]]
| SolubleOther = slightly soluble in [[alcohol]]
| MeltingPt = >465 °C decomp.
| MeltingPt = >465 °C decomp.
| pKa =
| pKa = 12.4
| pKb =
| pKb = 6.8
}}
}}
| Section7 = {{Chembox Hazards
| Section7 = {{Chembox Hazards

Revision as of 16:05, 7 June 2011

Dipotassium phosphate
Names
IUPAC name
Potassium hydrogen phosphate
Other names
Potassium monohydrogen phosphate
Phosphoric acid dipotassium salt
Potassium phosphate dibasic
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.028.940 Edit this at Wikidata
E number E340(ii) (antioxidants, ...)
UNII
  • InChI=1S/2K.H3O4P/c;;1-5(2,3)4/h;;(H3,1,2,3,4)/q2*+1;/p-2 checkY
    Key: ZPWVASYFFYYZEW-UHFFFAOYSA-L checkY
  • InChI=1/2K.H3O4P/c;;1-5(2,3)4/h;;(H3,1,2,3,4)/q2*+1;/p-2
    Key: ZPWVASYFFYYZEW-NUQVWONBAH
  • [K+].[K+].[O-]P([O-])(=O)O
Properties
K2HPO4
Molar mass 174.2 g/mol
Appearance white powder
deliquescent
Odor odorless
Density 2.44 g/cm3
Melting point >465 °C decomp.
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)
NFPA 704 four-colored diamondHealth 2: Intense or continued but not chronic exposure could cause temporary incapacitation or possible residual injury. E.g. chloroformFlammability 0: Will not burn. E.g. waterInstability 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogenSpecial hazards (white): no code
2
0
0
Flash point Non-flammable
Related compounds
Other cations
Disodium phosphate
Diammonium phosphate
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
checkY verify (what is checkY☒N ?)

Dipotassium phosphate (K2HPO4) - also phosphoric acid, dipotassium salt; dipotassium hydrogen orthophosphate; potassium phosphate, dibasic - is a highly water-soluble salt which is often used as a fertilizer, food additive and buffering agent. It is a common source of phosphorus and potassium.

The pH of a dipotassium phosphate solution is almost neutral. It is formed by the stoichiometric neutralization of phosphoric acid with potassium hydroxide:

H3PO4 + 2 KOH → K2HPO4 + 2 H2O

It reacts with phosphoric acid to generate monopotassium phosphate:

K2HPO4 + H3PO4 → 2 KH2PO4

Safety

As a food additive, Dipotassium phosphate is on the FDA's Generally recognized as safe, or GRAS, list of substances[1]. It is used in non-dairy creamers to prevent coagulation.[2]

References

  1. ^ "Database of Select Committee on GRAS Substances (SCOGS) Reviews". Retrieved 2008-03-22. (listed as potassium phosphate, dibasic)
  2. ^ "dipotassium phosphate". Retrieved 2009-01-06. (uses: Food Industry)