Dipotassium phosphate
IUPAC name
Potassium hydrogen phosphate
Other names
Potassium monohydrogen phosphate
Phosphoric acid dipotassium salt
Potassium phosphate dibasic
3D model (JSmol)
ECHA InfoCard 100.028.940 Edit this at Wikidata
EC Number
  • 231-834-5
E number E340(ii) (antioxidants, ...)
  • InChI=1S/2K.H3O4P/c;;1-5(2,3)4/h;;(H3,1,2,3,4)/q2*+1;/p-2 checkY
  • InChI=1/2K.H3O4P/c;;1-5(2,3)4/h;;(H3,1,2,3,4)/q2*+1;/p-2
  • [K+].[K+].[O-]P([O-])(=O)O
Molar mass 174.2 g/mol
Appearance white powder
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
NFPA 704 (fire diamond)
NFPA 704 four-colored diamondHealth 1: Exposure would cause irritation but only minor residual injury. E.g. turpentineFlammability 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
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).
☒N verify (what is checkY☒N ?)

Dipotassium phosphate (K2HPO4) (also dipotassium hydrogen orthophosphate; 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.[1] 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:[1]

H3PO4 + 2 KCl → K2HPO4 + 2 HCl


As a food additive, dipotassium phosphate is used in imitation dairy creamers, dry powder beverages, mineral supplements, and starter cultures.[2] It functions as an emulsifier, stabilizer and texturizer; it also is a buffering agent, and chelating agent especially for the calcium in milk products..[3]

As a food additive, dipotassium phosphate is generally recognized as safe by the United States Food and Drug Administration.[4]


  1. ^ a b Klaus Schrödter; Gerhard Bettermann; Thomas Staffel; Friedrich Wahl; Thomas Klein; Thomas Hofmann (2012). "Phosphoric Acid and Phosphates". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a19_465.pub3. ISBN 978-3527306732.
  2. ^ John H. Thorngate III; Seppo Salminen; Larry A. Branen; Michael P. Davidson, eds. (2001). "Food Phosphates". Food Additives. Food Science and Technology. Vol. 116. CRC Press. doi:10.1201/9780824741709.ch25. ISBN 978-0-8247-9343-2.
  3. ^ "What is dipotassium phosphate?". 30 April 2018. Retrieved 2020-09-09.
  4. ^ "Database of Select Committee on GRAS Substances (SCOGS) Reviews". Archived from the original on 2007-05-21. Retrieved 2008-03-22. (listed as "potassium phosphate, dibasic")