Disodium phosphate
Encyclopedia
Disodium hydrogen phosphate (Na2HPO4) is a sodium
salt of phosphoric acid
. It is a white powder that is highly hygroscopic and water soluble. 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. pH of disodium hydrogen phosphate water solution is between 8.0 and 11.0.
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Sodium
Sodium is a chemical element with the symbol Na and atomic number 11. It is a soft, silvery-white, highly reactive metal and is a member of the alkali metals; its only stable isotope is 23Na. It is an abundant element that exists in numerous minerals, most commonly as sodium chloride...
salt of phosphoric acid
Phosphoric acid
Phosphoric acid, also known as orthophosphoric acid or phosphoric acid, is a mineral acid having the chemical formula H3PO4. Orthophosphoric acid molecules can combine with themselves to form a variety of compounds which are also referred to as phosphoric acids, but in a more general way...
. It is a white powder that is highly hygroscopic and water soluble. 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. pH of disodium hydrogen phosphate water solution is between 8.0 and 11.0.
Preparation
It may be formed by reaction of stoichiometric quantities of sodium hydroxide and phosphoric acidPhosphoric acid
Phosphoric acid, also known as orthophosphoric acid or phosphoric acid, is a mineral acid having the chemical formula H3PO4. Orthophosphoric acid molecules can combine with themselves to form a variety of compounds which are also referred to as phosphoric acids, but in a more general way...
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- 2 NaOH + H3PO4 → Na2HPO4 + 2 H2O
Other uses
- Disodium phosphate is used in Cream of WheatCream of WheatCream of Wheat is a porridge-type breakfast food invented in 1893 by wheat millers in Grand Forks, North Dakota. The cereal is currently manufactured and sold by B&G Foods. Until 2007, it was the Nabisco brand made by Kraft Foods. It is similar in texture to grits, but made with farina instead...
to quicken cook time, as described on the ingredients panel of the product package. - Disodium phosphate is used in conjunction with trisodium phosphateTrisodium phosphateTrisodium phosphate is a cleaning agent, food additive, stain remover and degreaser. It is a white, granular or crystalline solid, highly soluble in water producing an alkaline solution....
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.