Title: Isocyanic Acid
CAS Registry Number: 75-13-8
Synonyms: Carbimide
Molecular Formula: CHNO
Molecular Weight: 43.02
Percent Composition: C 27.92%, H 2.34%, N 32.56%, O 37.19%
Line Formula: HN=C=O
Literature References: Prepn: J. Liebig, F. W?hler,
Ann. 39, 29 (1846); Steyermark,
J. Org. Chem. 28, 586 (1963); R. Vorhoeve, L. E. Trimble,
Science 202, 525 (1978). Crystal structure: Von Dohlen, Carpenter,
Acta Crystallogr. 8, 646 (1955). Review of prepn and properties: D. J. Belson, A. N. Strachan,
Chem. Soc. Rev. 11, 41-56 (1982).
See also Cyanic Acid.
Properties: Store in dil solns of carbon tetrachloride or ether at -30° to slow polymerization. The free acid in the vapor phase or in ether soln gives no indication of being a mixture, and all the evidence supports the iso structure, HNCO, whereas in aq soln cyanic acid HOCN is present: N. V. Sidgwick,
The Chemical Elements and Their Compounds vol. I (Oxford, 1950) p 673.
CAUTION: Strongly acidic, will blister skin.
