7659. Potassium Phosphate, Monobasic

Nomenclature

CAS number: 7778-77-0
Phosphoric acid potassium salt (1:1); potassium biphosphate; potassium acid phosphate; potassium dihydrogen phosphate; monopotassium phosphate; S"orensen's potassium phosphate.
H2KO4P; mol wt 136.09.
H 1.48%, K 28.73%, O 47.03%, P 22.76%.
KH2PO4.

Properties

Colorless crystals or white, granular powder; permanent in air; at 400° loses H2O, forming metaphosphate. d 2.34. Sol in ≈4.5 parts water. Insol in alcohol. pH 4.4-4.7.

Use

In buffers for determination of pH. Pharmaceutic aid (buffering agent).