Definition

1. Noun:
   • A highly poisonous, colorless, volatile liquid: Hydrocyanic acid is a chemical compound consisting of hydrogen cyanide dissolved in water. It is extremely toxic and has a faint odor of bitter almonds.
   • A solution used in industry and pest control: In diluted forms, it is used for fumigation and as a chemical intermediate in the synthesis of various organic compounds.

Usage Examples

• Noun:
  • Hydrocyanic acid is a deadly poison that can cause rapid respiratory failure.
  • The laboratory uses a weak solution of hydrocyanic acid in the synthesis process.
  • Fumigation with hydrocyanic acid requires extreme safety precautions.

Advanced Usage

• Technical/Industrial Context: The term is used precisely in chemistry, toxicology, and industrial manufacturing.
  • The safety data sheet for hydrocyanic acid details strict handling protocols.
• Historical Context: It has been infamously used as a chemical weapon and in executions.
  • Hydrocyanic acid was the agent used in some gas chambers.

Variants and Related Words

• Hydrogen cyanide (HCN): The pure gaseous or liquid compound from which hydrocyanic acid is derived.
  • Hydrogen cyanide gas is even more volatile than its aqueous solution.
• Prussic acid: An older, synonymous name for hydrocyanic acid.
  • Prussic acid was a common term in early chemical texts.
• Cyanide: A related term referring to salts containing the CN⁻ ion, which share similar toxic properties.
  • The toxicity of sodium cyanide is related to its release of cyanide ions, similar to the mechanism of hydrocyanic acid.

Synonyms

• Prussic acid (historical/technical synonym)
• HCN(aq) (chemical notation for the aqueous solution)

Related Phrases / Compounds

• Hydrocyanic acid gas: Refers to hydrogen cyanide in its gaseous state.
  • The fumigation tent was filled with hydrocyanic acid gas.
• Weak hydrocyanic acid: Refers to diluted solutions used in controlled industrial applications.
  • Weak hydrocyanic acid is a precursor in some pharmaceutical syntheses.

Important Notes

• Extreme Toxicity: This is the primary characteristic associated with the term. It inhibits cellular respiration.
• Chemical Property: It is a weak acid in aqueous solution, but its toxicity is not related to its acidity.

Noun

1. a solution of hydrogen cyanide in water; weak solutions are used in fumigating and in the synthesis of organic compounds