7614. Potassium Bisulfide

Nomenclature

CAS number: 1310-61-8
Potassium hydrosulfide; potassium hydrogen sulfide; potassium sulfhydrate.
HKS; mol wt 72.17.
H 1.40%, K 54.18%, S 44.43%.
KHS.

Description and references

Prepd industrially from Ca(HS)2 and K2SO4: Hene, DE 380385 (1922); from H2S and K2S: Bassett, US 1662735 (1925); Strosacker, Jones, US 1771384 (1926 to Dow). Prepn of pure material by the action of dry H2S upon potassium metal dissolved in abs ethanol: Rule, J. Chem. Soc. 99, 558, 564 (1911); West, Z. Kristallogr. 88, 102 (1934).

Properties

Colorless, deliquescent crystals or white, strongly hygroscopic, cryst mass. Usually present as the hemihydrate. Trigonal system. d 1.70. Rapidly becomes yellow on exposure to air with formation of polysulfides and H2S. Becomes anhydr at 175-200°. mp 450-510° forming a dark red liquid. Heat of formation: +62.5 kcal. Heat of soln at 17°: +0.77 kcal, for hemihydrate at 16°: +0.62 kcal. Freely sol in water, alcohol.