Sodium dihydrogen phosphate
monobasic sodium phosphate;
sodium dihydrogen phosphate;
3D model (JSmol)
|E number||E339(i) (antioxidants, ...)|
CompTox Dashboard (EPA)
|Molar mass||119.98 g/mol|
|Appearance||White powder or crystals|
|Density||2.36 g/cm3 (anhydrous)|
|59.90 g/100 mL (0°C)|
|NFPA 704 (fire diamond)|
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
|what is ?)(|
Monosodium phosphate (MSP), also known as monobasic sodium phosphate and sodium dihydrogen phosphate, is an inorganic compound of sodium with a dihydrogen phosphate (H2PO4-) anion. One of many sodium phosphates, it is a common industrial chemical. The salt exists in an anhydrous form, as well as mono- and dihydrates.
Heating this salt above 169 °C gives the corresponding sodium acid pyrophosphate:
Phosphates are often used in foods and in water treatment. The pH of such formulations is generally adjusted by mixtures of various sodium phosphates, such as this salt. The sodium chloride equivalent value, or E-Value, is 0.49. It is soluble in 4.5 parts water.
Monosodium phosphate is used to detect the presence of magnesium ions in salts. Formation of a white precipitate on the addition of ammonium chloride, ammonium hydroxide and monosodium phosphate to an aqueous or dilute HCl solution of the salt indicates presence of magnesium ions.