Potassium hydrosulfide
IUPAC name
Potassium hydrosulfide
Other names
Potassium bisulfide, Potassium sulfhydrate, potassium hydrogen sulfide
3D model (JSmol)
ECHA InfoCard 100.013.803 Edit this at Wikidata
EC Number
  • 215-182-9
  • InChI=1S/K.H2S/h;1H2/q+1;/p-1 ☒N
  • InChI=1/K.H2S/h;1H2/q+1;/p-1
  • [SH-].[K+]
Molar mass 72.171 g/mol
Appearance white solid
Density 1.68–1.70 g/cm3
Melting point 455 °C (851 °F; 728 K)
Occupational safety and health (OHS/OSH):
Main hazards
Flammable solid, stench, releases hydrogen sulfide
NFPA 704 (fire diamond)
NFPA 704 four-colored diamondHealth 3: Short exposure could cause serious temporary or residual injury. E.g. chlorine gasFlammability 2: Must be moderately heated or exposed to relatively high ambient temperature before ignition can occur. Flash point between 38 and 93 °C (100 and 200 °F). E.g. diesel fuelInstability 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogenSpecial hazards (white): no code
Related compounds
Other anions
Potassium hydroxide
Other cations
Sodium hydrosulfide
Related compounds
potassium sulfide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Potassium hydrosulfide is the inorganic compound with the formula KSH. This colourless salt consists of the cation K+ and the bisulfide anion [SH]. It is the product of the half-neutralization of hydrogen sulfide with potassium hydroxide. The compound is used in the synthesis of some organosulfur compounds.[1] Aqueous solutions of potassium sulfide consist of a mixture of potassium hydrosulfide and potassium hydroxide.

The structure of the potassium hydrosulfide resembles that for potassium chloride. Their structure is however complicated by the non-spherical symmetry of the SH anions, but these tumble rapidly in the solid.[2]

Addition of sulfur gives dipotassium pentasulfide.


It is prepared by neutralizing aqueous KOH with H2S.[3][4]


  1. ^ Dittmer, Donald C. (2001). "Potassium Hydrogen Sulfide". In Paquette, L. (ed.). Encyclopedia of Reagents for Organic Synthesis. J. Wiley & Sons, New York. doi:10.1002/047084289X.rp227. ISBN 0471936235.
  2. ^ Haarmann, F; Jacobs, H.; Roessler, E.; Senker, J. (2002). "Dynamics of Anions and Cations in Hydrogensulfides of Alkali Metals (NaHS, KHS, RbHS): A Proton Nuclear Magnetic Resonance Study". Journal of Chemical Physics. 117 (3): 1269–1276. Bibcode:2002JChPh.117.1269H. doi:10.1063/1.1483860.
  3. ^ Kurzer, F.; Lawson, A. (1962). "Thiobenzoylthioglycolic Acid". Organic Syntheses. 42: 100. doi:10.15227/orgsyn.042.0100.
  4. ^ Robert L. Frank and James R. Blegen (1948). "Benzoyl Disulfide". Organic Syntheses. 28: 16. doi:10.15227/orgsyn.028.0016.