Monopotassium arsenate is the
inorganic compound with the formula KH
2AsO
4. A white solid, this salt is used to prepared other arsenic-containing compounds, mainly pesticides. It is prepared by
calcining
Calcination refers to thermal treatment of a solid chemical compound (e.g. mixed carbonate ores) whereby the compound is raised to high temperature without melting under restricted supply of ambient oxygen (i.e. gaseous O2 fraction of air), gener ...
arsenic oxide and potassium nitrate, followed by extraction with water.
Relevant acid-base equilibria for aqueous solutions of this diprotic acid derived from
arsenic acid
Arsenic acid or trihydrogen arsenate is the chemical compound with the formula . More descriptively written as , this colorless acid is the arsenic analogue of phosphoric acid. Arsenate and phosphate salts behave very similarly. Arsenic acid as ...
are as follows:
:H
3AsO
4 + H
2O + H
3O
+ (p''K''
a1 = 2.19)
: + H
2O + H
3O
+ {{pad, 2em(p''K''
a2 = 6.94)
Related compounds
*
Trisodium arsenate
Sodium arsenate is the inorganic compound with the formula Na3AsO4. Related salts are also called sodium arsenate, including Na2HAsO4 ( disodium hydrogen arsenate) and NaH2AsO4 ( sodium dihydrogen arsenate). The trisodium salt is a white or col ...
, Na
3AsO
4
*
Disodium hydrogen arsenate
Disodium hydrogen arsenate is the inorganic compound with the formula Na2HAsO4.7H2O. The compound consists of a salt and seven molecules of water of crystallization although for simplicity the formula usually omits the water component. The other ...
, Na
2HAsO
4
References
Arsenates
Potassium compounds