potassium cyanide

Also known as potassium salt of hydrocyanic acid, KCN

inorganic compound

OverviewAI-generated

Potassium cyanide is a chemical compound with the formula KCN. It has a molecular mass of 64.967 and a density of 1.55. The substance melts at 1173 and boils at 2957. Its solubility is 72, while its vapor pressure is 0. The median lethal dose is 11, and the immediately dangerous to life or health level is 25. Exposure limits are set at 5 for both time-weighted average and ceiling values.

The compound has a canonical SMILES notation of [C-]#N.[K+]. It possesses two hydrogen bond acceptors and no hydrogen bond donors, with a topological polar surface area of 23.8. The IUPAC name is potassium cyanide. It is referenced by 613 other encyclopedia articles and has 3988 associated PubMed entries.

Synthesized by Vinony from 26 facts across 4 sources: Wikidata, PubChem, PubMed, Vinony graph. Generated from structured data (not the Wikipedia text) and checked against those facts — may still contain errors.

Chemical data

Formula: CKN
Molecular weight: 65.116 g/mol
IUPAC name: potassium cyanide
SMILES: [C-]#N.[K+]
InChIKey: NNFCIKHAZHQZJG-UHFFFAOYSA-N
Polar surface area: 23.8 Å²
H-bond donors: 0
H-bond acceptors: 2
Formal charge: 0

via PubChem

Research

3,988 papers

Fatality from potassium gold cyanide poisoning.BMJ case reports · 2019Harmon E, Lebin J, Murphy D et al.DOI: 10.1136/bcr-2019-229947
Potassium cyanide poisoning.Indian pediatrics · 1992Prajapati NC, Puri RK, Sarangi MP et al.
Comparative multi-species analysis of potassium cyanide toxicity.Marine pollution bulletin · 2022Tez S, Oral R, Koçbaş F et al.DOI: 10.1016/j.marpolbul.2022.113965
The effects of potassium cyanide on tardigrade Paramacrobiotus experimentalis.Scientific reports · 2025Bartylak T, Kayastha P, Wieczorkiewicz F et al.DOI: 10.1038/s41598-025-05927-9
A fatal case of potassium gold cyanide poisoning.Journal of forensic sciences · 2025Seol I, Lee S, Kim H et al.DOI: 10.1111/1556-4029.15654
[Potassium cyanide poisoning].Ugeskrift for laeger · 1981Jensen PH, Nielsen SV
[Potassium cyanide poisoning treated with hydroxocobalamin].Annales francaises d'anesthesie et de reanimation · 1990Tassan H, Joyon D, Richard T et al.DOI: 10.1016/s0750-7658(05)80252-7
Potassium cyanide protects Escherichia coli from complement killing by the inhibition of C3 convertase activity.Immunological investigations · 1993Bloch EF, Rahbar M, Wright AK et al.DOI: 10.3109/08820139309063396

via PubMed

~6 min read

Encyclopedic overview

Potassium cyanide is a compound with the formula KCN. It is a colorless salt, similar in appearance to sugar, that is highly soluble in water. Most KCN is used in gold mining, organic synthesis, and electroplating. Smaller applications include chemical gilding and buffing of jewelry. Potassium cyanide is highly toxic, and a dose of 200 to 300 milligrams will kill nearly any human.

The moist solid emits small amounts of hydrogen cyanide due to hydrolysis (reaction with water). Hydrogen cyanide is often described as having an odor resembling that of bitter almonds.

Excerpted from Wikipedia’s “potassium cyanide” article, available under the CC BY-SA 4.0 licence.