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isocyanic acid

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isocyanic acid

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Also known as cyanic acid, hydrogen cyanate, oxidoazanediidocarbon, HNCO, [C(NH)O], HN=C=O, hydrogen isocyanate, carbimide

chemical compound of structural formula HNCO

Chemical data

Formula
CHNO
Molecular weight
43.025 g/mol
IUPAC name
isocyanic acid
SMILES
C(=N)=O
InChIKey
OWIKHYCFFJSOEH-UHFFFAOYSA-N
XLogP
1
Polar surface area
40.9 Ų
H-bond donors
1
H-bond acceptors
2
Formal charge
0

via PubChem

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Encyclopedic overview

Isocyanic acid is a chemical compound with the structural formula HNCO, which is often written as H−N=C=O. It is a colourless, volatile and poisonous gas, condensing at 23.5 °C. It is the predominant tautomer and an isomer of cyanic acid (aka. cyanol) (H−O−C≡N), and the monomer of cyanuric acid.

The derived anion of isocyanic acid is the same as the derived anion of cyanic acid, and that anion is [N=C=O], which is called cyanate. The related functional group −N=C=O is isocyanate; it is distinct from cyanate (−O−C≡N), fulminate (−O−N≡C), and nitrile oxide (−C≡N−O).

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