Potassium thiocyanate
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Names | |
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Other names
potassium sulfocyanate
potassium isothiocyanate potassium thiocyanide | |
Identifiers | |
ECHA InfoCard | 100.005.792 |
PubChem CID
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RTECS number |
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CompTox Dashboard (EPA)
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Properties | |
KSCN | |
Molar mass | 97.181 g/mol |
Appearance | colorless crystals deliquescent |
Odor | odorless |
Density | 1.886 g/cm3 |
Melting point | 173.2 °C |
Boiling point | 500 °C (decomp) |
177 g/100 mL (0 °C) 217 g/100 mL (20 °C) | |
Solubility in other solvents | e.g. ethanol acetone:21.0 g/100 mL |
Hazards | |
NFPA 704 (fire diamond) | |
Lethal dose or concentration (LD, LC): | |
LD50 (median dose)
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854 mg/kg |
Related compounds | |
Other anions
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Potassium cyanate Potassium cyanide |
Other cations
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Sodium thiocyanate Ammonium thiocyanate |
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 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. 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.
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 (or Iron (III) Chloride), the product of the reaction is a blood red solution. Thus this chemical is often used to create the effect of 'stigmata'. Because both solutions are colourless, 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.
References
- ^ Smith, P. A. S.; Kan, R. O. (1973). "2a-Thiohomophthalimide". Organic Syntheses
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: CS1 maint: multiple names: authors list (link); Collected Volumes, vol. 5, p. 1051. - ^ 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. - ^ van Tamelen, E. E. (1963). "Cyclohexenesulfide". Organic Syntheses; Collected Volumes, vol. 4, p. 232.