Potassium cyanide is an inorganic compound with the formula KCN. This colorless crystalline compound, similar in appearance to sugar, is highly soluble in water. Most KCN is used in gold mining, organic synthesis, and electroplating. Smaller applications include jewelry for chemical gilding and buffing.
KCN is highly toxic. The moist solid emits small amounts of hydrogen cyanide due to hydrolysis, which smells like bitter almonds. Not everyone, however, can smell this odor: the ability to do so is a genetic trait.
It is used by entomologists as a killing agent in collecting jars, as most insects succumb within seconds, minimizing damage of even highly fragile specimens.
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