7656. Potassium Persulfate

Nomenclature

CAS number: 7727-21-1
Peroxydisulfuric acid ([(HO)S(O)2]2O2) potassium salt (1:2); potassium peroxydisulfate.
K2O8S2; mol wt 270.32.
K 28.93%, O 47.35%, S 23.72%.
K2S2O8.

Description and references

The article of commerce contains 93-97% K2S2O8.

Properties

Colorless or white, odorless crystals. Oxidizer. Keep well closed in a cool place. Gradually dec, losing available oxygen; dec more quickly at higher temps; completely dec ≈100°. Sol in ≈50 parts water, 25 parts water at 40°. Aq soln dec at ordinary temp and more rapidly on warming; aq soln is acid. Insol in alc.

Use

Bleaching fabrics, soaps; in photography under the name Anthion to remove last traces of thiosulfate from plates and paper; as an oxidizing agent in analytical chemistry.