potassium cyanide

[pə′tas·ē·əm ′sī·ə‚nīd]

(inorganic chemistry)

KCN Poisonous, white, deliquescent crystals with bitter almond taste; soluble in water, alcohol, and glycerol; used for metal extraction, for electroplating, for heat-treating steel, and as an analytical reagent and insecticide.

The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Potassium Cyanide

KCN, a colorless, hygroscopic, crystalline compound.

Potassium cyanide has a melting point of 635°C and a density of 1.56 g/cm³ at 25°C and is readily soluble in water (41.7 percent soluble at 25°C and 55 percent soluble at 103.3°C). In aqueous solution it undergoes hydrolysis, forming hydrocyanic acid, HCN. The hydrolysis constant of KCN is 2.54 × 10^–5 at 25°C. Potassium cyanide has a great tendency to form complexes, such as potassium ferrocyanide, K₄[Fe(CN)₆] · 3H₂O.

In industry potassium cyanide is produced mainly by neutralizing HCN with potassium hydroxide, KOH. Information on the uses of potassium cyanide can be found in CYANIDE.Potassium cyanide is highly toxic. Its effect on the body and safety rules for its use are discussed in HYDROCYANIC ACID.

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References in periodicals archive

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The lethal dose in adults is 200300 mg of potassium cyanide 4,5).

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TOKYO, Jan 29 (Reuters) -- Envelopes containing threatening letters and a powder believed to be potassium cyanide have been sent to over a dozen Japanese companies including newspapers and drug makers over the past several days, local media reported on Tuesday.

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You will find it contains a pure grade of potassium cyanide so please do not consider this letter a mere threat.

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They met at a McDonald's in Waltham, and Camuti allegedly bought two iced coffees, adding two teaspoons of potassium cyanide to one and giving it to Rakes, who drank it.

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In this process, a previously made article was suspended in a solution of silver dissolved in potassium cyanide and water.

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Despite the fact that Stalin had suffered minor strokes before, Pirjavec claims the then 74-year-old had been poisoned with potassium cyanide.

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Cyanide has also been used for judicial execution in some parts of the United States, where cyanide was generated by reaction between potassium cyanide dropped into a compartment containing sulphuric acid, directly below the chair in the gas chamber.

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