RHODIZONIC ACID DIPOTASSIUM SALT

violet to black powder

Potassium rhodizonate is suitable reagent for the preparation of staining solution used in the rhodizonate test for the detection of lead. It is suitable reagent used in the preparation of barium, thallium, ammonium and silver salts rhodizonic acid by metathesis in aqueous solution.
It may be used in the following studies:

• To cocrystallize plutonium and radium from urine in the plutonium and radium assay of urine.
• As a dye in the spectrophotometric determination of sulfate ion.
• To determine the acid dissociation constants of rhodizonic acid by pH potentiometric titration of potassium rhodizonate with standardized HCl.
• As a staining agent for plagioclase in the petrographic study.

Potassium rhodizonate (3,4,5,6-Tetraoxocyclohexene-1,2-diol dipotassium salt, Rhodizonic acid potassium salt), a benzoquinone derivative, is the potassium salt of rhodizonic acid. Its crystalline structure has been reported and it exhibits space group Fddd. Rhodizonate dianion undergoes various thermal and photochemical reactions with various oxidizing reagents in aqueous solution.