Misplaced Pages

Revision as of 17:29, 25 August 2020

Potassium thiocyanate

Names
Other names Potassium sulfocyanate Potassium isothiocyanate Potassium thiocyanide Potassium rhodanide
Identifiers
CAS Number	333-20-0
3D model (JSmol)	Interactive image
ChEBI	CHEBI:30951
ChemSpider	9150
ECHA InfoCard	100.005.792
PubChem CID	516872
RTECS number	XL1925000
UNII	TM7213864A
CompTox Dashboard (EPA)	DTXSID7029619
InChI InChI=1S/CHNS.K/c2-1-3;/h3H;/q;+1/p-1Key: ZNNZYHKDIALBAK-UHFFFAOYSA-M InChI=1/CHNS.K/c2-1-3;/h3H;/q;+1/p-1Key: ZNNZYHKDIALBAK-REWHXWOFAT
SMILES C(#N).
Properties
Chemical formula	KSCN
Molar mass	97.181 g mol
Appearance	Colorless deliquescent crystals
Odor	Odorless
Density	1.886 g/cm
Melting point	173.2 °C (343.8 °F; 446.3 K)
Boiling point	500 °C (932 °F; 773 K) (decomposes)
Solubility in water	177 g/100 mL (0 °C) 217 g/100 mL (20 °C)
Solubility	acetone: 21.0 g/100 mL ethanol: soluble
Magnetic susceptibility (χ)	−48.0·10 cm/mol
Hazards
NFPA 704 (fire diamond)	2 0 0
Lethal dose or concentration (LD, LC):
LD50 (median dose)	854 mg/kg (oral, rat)
Safety data sheet (SDS)	ICSC 1088
Related compounds
Other anions	Potassium cyanate Potassium cyanide
Other cations	Sodium thiocyanate Ammonium thiocyanate
Except where otherwise noted, data are given for materials in their standard state (at 25 °C , 100 kPa). N verify (what is  ?) Infobox references

Potassium thiocyanate is the chemical compound with the molecular formula KSCN. It is an important salt of the thiocyanate anion, one of the pseudohalides. The compound has a low melting point relative to most other inorganic salts.

Use in chemical synthesis

Aqueous KSCN reacts almost quantitatively with Pb(NO₃)₂ to give Pb(SCN)₂, which has been used to convert acyl chlorides to isothiocyanates.

KSCN converts ethylene carbonate to ethylenesulfide. For this purpose, the KSCN is first melted under vacuum to remove water. In a related reaction, KSCN converts cyclohexene oxide to the corresponding episulfide.

C₆H₁₀O + KSCN → C₆H₁₀S + KOCN

KSCN is also the starting product for the synthesis of carbonyl sulfide.

Other uses

Dilute aqueous KSCN is occasionally used for moderately realistic blood effects in film and theater. It can be painted onto a surface or kept as a colorless solution. When in contact with ferric chloride solution (or other solutions containing Fe), the product of the reaction is a solution with a blood red colour, due to the formation of the thiocyanatoiron complex ion. Thus this chemical is often used to create the effect of 'stigmata'. Because both solutions are colorless, they can be placed separately on each hand. When the hands are brought into contact, the solutions react and the effect looks remarkably like stigmata.

Similarly, this reaction is used as a test for Fe in the laboratory.

References

1. Chambers, Michael. "ChemIDplus - 333-20-0 - ZNNZYHKDIALBAK-UHFFFAOYSA-M - Potassium thiocyanate [NF] - Similar structures search, synonyms, formulas, resource links, and other chemical information". chem.sis.nlm.nih.gov. Retrieved 19 April 2018.
2. Smith, P. A. S.; Kan, R. O. (1973). "2a-Thiohomophthalimide". Organic Syntheses{{cite journal}}: CS1 maint: multiple names: authors list (link); Collected Volumes, vol. 5, p. 1051.
3. Searles, S.; Lutz, E. F.; Hays, H. R.; Mortensen, H. E. (1973). "Ethylenesulfide". Organic Syntheses{{cite journal}}: CS1 maint: multiple names: authors list (link); Collected Volumes, vol. 5, p. 562.
4. van Tamelen, E. E. (1963). "Cyclohexenesulfide". Organic Syntheses; Collected Volumes, vol. 4, p. 232.

• Thiocyanates
• Potassium compounds
• Photographic chemicals