The chemical formula for sodium dihydrogen phosphate is NaH2PO4. Sodium dihydrogen phosphate is also known as monosodium phosphate and sodium phosphate. NaH2PO4 is the anhydrous form, which means it does not contain water.
The chemical formula for sodium dihydrogen phosphate monohydrate is NaH2PO4 · H2O. Several hydrates of NaH2PO4 exist. Each is represented in the same way, but a number in front of H2O shows how many molecules of water are present for each molecule of sodium dihydrogen phosphate.
Sodium dihydrogen phosphate acts as a laxative. It is also used as a food additive for both humans and animals, as the phosphate in it is essential for metabolic processes.