Hydrogen cyanide

CAS Registry Number®

74-90-8

CAS Name

Hydrogen cyanide

Molecular Formula

CHN

Molecular Mass

27.03

Cite this Page

Hydrogen cyanide.   CAS Common Chemistry.   CAS, a division of the American Chemical Society, n.d.   http://commonchemistry.cas.org/ChemicalDetail.aspx?ref=74-90-8 (retrieved 2025-07-18) (CAS RN: 74-90-8).  Licensed under the Attribution-Noncommercial 4.0 International License (CC BY-NC 4.0).

Compound Properties

  • Boiling Point (1)

    25.6 °C

  • Melting Point (1)

    -13.4 °C

  • Density (1)

    0.687 g/cm³

Source(s)

  • (1) Hazardous Substances Data Bank data were obtained from the National Library of Medicine (US)

Other Names and Identifiers

InChI

InChI=1S/CHN/c1-2/h1H

InChIKey

InChIKey=LELOWRISYMNNSU-UHFFFAOYSA-N

SMILES

C#N

Canonical SMILES

N#C

Other Names for this Substance

  • Hydrocyanic acid
  • Formic anammonide
  • Formonitrile
  • Hydrogen cyanide
  • Prussic acid

View All

Deleted or Replaced CAS Registry Numbers

191234-22-7, 341972-31-4, 2622237-35-6