Potassium sulfide

Crystal structure
K + : __   / S 2− : __
General
Surname	Potassium sulfide
other names	Dipotassium monosulfide Dipotassium sulfide Potassium monosulfide Potassium Sulfuratum POTASSIUM SULFIDE ( INCI )
Ratio formula	K 2 S
Brief description	hygroscopic, colorless to yellowish or brownish-red solid with a smell of hydrogen sulfide
External identifiers / databases
CAS number 1312-73-8 EC number 215-197-0 ECHA InfoCard 100,013,816 PubChem 14800 ChemSpider 14116 Wikidata Q408920
Drug information
ATC code	A12 BA
properties
Molar mass	110.26 g mol −1
Physical state	firmly
density	1.81 g cm −3 (14 ° C)
Melting point	840 ° C
solubility	easily decomposes in water
safety instructions
Please note the exemption from the labeling requirement for drugs, medical devices, cosmetics, food and animal feed GHS hazard labeling from  Regulation (EC) No. 1272/2008 (CLP) , expanded if necessary danger H and P phrases H: 251-314-400 EUH: 031 P: 280-273-301 + 330 + 331-305 + 351 + 338-308 + 310
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Potassium sulfide is a potassium salt of hydrogen sulfide (H ₂ S).

properties

In the event of contact with air, spontaneous self-ignition can occur. Potassium sulfide is hygroscopic and the hydrates formed are not flammable. Contact with acids leads to the release of toxic hydrogen sulfide . In the presence of oxidizing agents , sulfur dioxide is produced . Shock or friction can cause an explosion. Potassium sulphide gradually converts to potassium thiosulphate in air .

${\displaystyle \mathrm {2\ K_{2}S\ +\ 2\ O_{2}+\ H_{2}O\longrightarrow \ K_{2}S_{2}O_{3}\ +\ 2\ KOH} }$

Aqueous solutions of potassium sulfide are strongly basic and react violently with acids.

presentation

One possible display method is the saturation of a potassium hydroxide solution with hydrogen sulfide. Potassium hydrogen sulfide forms in the solution , which can be converted into potassium sulfide with an equivalent amount of potassium hydroxide solution.

${\displaystyle \mathrm {KOH\ +\ H_{2}S\longrightarrow \ KHS\ +\ H_{2}O} }$

${\displaystyle \mathrm {KHS\ +\ KOH\longrightarrow \ K_{2}S\ +\ H_{2}O} }$

The salt crystallizes from the solution with 5 mol of water of crystallization . The rough drainage is accompanied by partial decomposition. The method given for sodium sulfide is successful.

In principle, potassium sulfide can also be obtained by melting sulfur and potassium carbonate together . The brown mixed product ( sulfur liver ) is also available in stores as potassium sulphide, but in addition to this it also contains potassium polysulphide , potassium thiosulphate and potassium sulphate .

toxicology

Potassium sulphide is corrosive to the skin, eyes and respiratory tract. Depending on the exposure, redness, blistering and burns appear externally. Ingestion causes nausea, vomiting, diarrhea and colic. Nausea and vomiting also occur with inhalation. In addition, there is a strong urge to cough, sore throat, headache. In the worst case, pulmonary edema can develop .

Individual evidence

1. ↑ Entry on POTASSIUM SULFIDE in the CosIng database of the EU Commission, accessed on March 4, 2020.
2. ↑ ^{a b c d e f} Entry on potassium sulphide in the GESTIS substance database of the IFA , accessed on January 8, 2018(JavaScript required) .
3. ↑ Entry on Dipotassium sulphide in the Classification and Labeling Inventory of the European Chemicals Agency (ECHA), accessed on February 1, 2016. Manufacturers or distributors can expand the harmonized classification and labeling .
4. ↑ Data sheet potassium sulfide (PDF) from Merck , accessed on January 29, 2018.
5. ↑ G. Brauer (Ed.), Handbook of Preparative Inorganic Chemistry 2nd ed., Vol. 1, Academic Press 1963, pp. 360-361.