Potassium thiocyanate

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Potassium thiocyanate
Other names potassium sulfocyanate
potassium isothiocyanate
potassium thiocyanide
Identifiers
CAS number [333-20-0]
RTECS number XL1925000
Properties
Molecular formula KSCN
Molar mass 97.18 g/mol
Appearance colorless crystals
deliquescent
Density 1.89 g/cm3, solid
Melting point

173 °C

Boiling point

500 °C

Solubility in water 2170 g/L
Solubility in other solvents e.g. ethanol
acetone:210 g/L
Hazards
Main hazards toxic
R-phrases 20/21/22-32-52/53
S-phrases 13-61
Related compounds
Other cations NaSCN
Related compounds Potassium cyanide
Potassium cyanate
Except where noted otherwise, data are given for
materials in their standard state
(at 25 °C, 100 kPa)

Infobox disclaimer and 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.

[edit] Use in chemical synthesis

Aqueous KSCN reacts almost quantitatively with Pb(NO3)2 to give Pb(SCN)2. The lead compound has been used to convert acyl chlorides to the thiocyanates.[1]

KSCN converts ethylene carbonate to ethylenesulfide.[2] 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.[3]

C6H10O + KSCN → C6H10S + KOCN

Its the starting product for the synthesis of carbonyl sulfide.

[edit] 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 colourless solution. When in contact with ferric chloride solution, the product of the reaction is a blood red solution.

[edit] References

  1. ^ Smith, P. A. S.; Kan, R. O. (1973). "2a-Thiohomophthalimide". Org. Synth.; Coll. Vol. 5: 1051. 
  2. ^ Searles, S.; Lutz, E. F.; Hays, H. R.; Mortensen, H. E. (1973). "Ethylenesulfide". Org. Synth.; Coll. Vol. 5: 562. 
  3. ^ van Tamelen, E. E. (1963). "Cyclohexenesulfide". Org. Synth.; Coll. Vol. 4: 232.