Disodium phosphate

Disodium phosphate
Disodium phosphate
CAS number 7558-79-4 YesY
10028-24-7 (dihydrate)
7782-85-6 (heptahydrate)
10039-32-4 (dodecahydrate)
ChemSpider 22625 YesY
EC number 231-448-7
ChEBI CHEBI:34683 YesY
RTECS number WC4500000
Jmol-3D images Image 1
Molecular formula Na2HPO4
Molar mass 141.96 g/mol
Appearance White crystalline solid
Density 0.5–1.2 g/cm3
Melting point

250 ºC decomp.

Solubility in water 7.7 g/100 ml (20 ºC)
EU Index Not listed
Main hazards Irritant
NFPA 704
NFPA 704.svg
Flash point Non-flammable
Related compounds
Other anions sodium phosphite
Other cations Dipotassium phosphate
Diammonium phosphate
Related compounds Monosodium phosphate
Trisodium phosphate
 N phosphate (verify) (what is: YesY/N?)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Disodium hydrogen phosphate (Na2HPO4) is a sodium salt of phosphoric acid. It is a white powder that is highly hygroscopic and water soluble.[1] It is therefore used commercially as an anti-caking additive in powdered products. It is also known as disodium hydrogen orthophosphate, sodium hydrogen phosphate or sodium phosphate dibasic. It is commercially available in both the hydrated and anhydrous forms.[2] pH of disodium hydrogen phosphate water solution is between 8.0 and 11.0.


It may be formed by reaction of stoichiometric quantities of sodium hydroxide and phosphoric acid:

2 NaOH + H3PO4 → Na2HPO4 + 2 H2O

Other uses

  • Disodium phosphate is used in Cream of Wheat to quicken cook time, as described on the ingredients panel of the product package.
  • Disodium phosphate is used in conjunction with trisodium phosphate in many steam-boiler applications. It supplies the inventory of free phosphates to retard calcium scale formation.
  • Monobasic and dibasic sodium phosphate is used as a saline laxative to treat constipation or to clean the bowel before a colonoscopy.


Wikimedia Foundation. 2010.

Игры ⚽ Нужно решить контрольную?

Look at other dictionaries:

  • disodium phosphate — noun or disodium hydrogen phosphate : sodium phosphate 1b * * * /duy soh dee euhm/, Chem. See sodium phosphate (def. 2). [DI 1 + SODIUM] …   Useful english dictionary

  • disodium phosphate — noun Date: circa 1928 a sodium phosphate Na2HPO4 …   New Collegiate Dictionary

  • disodium phosphate — /duy soh dee euhm/, Chem. See sodium phosphate (def. 2). [DI 1 + SODIUM] * * * …   Universalium

  • Disodium inosinate — IUPAC name Disodium [(2R,3S,4R,5R) 3,4 dihydroxy 5 (6 oxo 3H purin 9 yl)oxolan 2 yl …   Wikipedia

  • Disodium pyrophosphate — IUPAC name Disodium dihydrogen diphosphate …   Wikipedia

  • disodium hydrogen phosphate — I. noun see disodium phosphate II. noun see sodium phosphate …   Useful english dictionary

  • Disodium guanylate — IUPAC name disodium [(2R,3S,4R,5R) 5 (2 amino 6 oxo 3H purin 9 yl) 3,4 dihydroxy 2 …   Wikipedia

  • Phosphate — A form of phosphoric acid. Calcium phosphate makes bones and teeth hard. * * * 1. A salt or ester of phosphoric acid. For individual phosphates not listed here, see under the name of the base. 2. The trivalent ion, PO43−. bone p. SYN: tribasic… …   Medical dictionary

  • phosphate buffer — a buffer system composed of acid phosphate and sodium or potassium salts, e.g., monosodium and disodium acid phosphate; in the body, it is important in regulating the pH of the renal tubular fluids …   Medical dictionary

  • Trisodium phosphate — Not to be confused with Sodium triphosphate. Trisodium phosphate[1] …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”