Title: Hydrogen Cyanide
CAS Registry Number: 74-90-8
CAS Name: Hydrocyanic acid
Additional Names: prussic acid
Molecular Formula: CHN
Molecular Weight: 27.03
Percent Composition: C 44.43%, H 3.73%, N 51.82%
Line Formula: HCN
Literature References: Prepd on a large scale by the catalytic oxidation of ammonia-methane mixtures (Andrussow Process): see Andrussow, Angew. Chem. 48, 593 (1935); Maffezzoni, Chim. Ind. (Milan) 34, 460 (1952); Faith, Keyes & Clark's Industrial Chemicals, F. A. Lowenheim, M. K. Moran, Ed. (Wiley-Interscience, New York, 4th ed., 1975) pp 482-486. Prepd in the lab by acidifying NaCN or K4[Fe(CN)6]: Glemser in Handbook of Preparative Inorganic Chemistry vol. 1, G. Brauer, Ed. (Academic Press, New York, 2nd ed., 1963) pp 658-660. Review of toxicology and human exposure: Toxicological Profile for Cyanide (PB98-101207, 1997) 291 pp.
Properties: Colorless gas or liquid; characteristic odor. Burns in air with a blue flame. Flammable. Intensely poisonous even when mixed with air. Must be handled by specially trained experts. mp -13.4°. bp 25.6°. d(gas) 0.941 (air = 1); d(liq) 0.687. Very weakly acid (does not redden litmus). Miscible with water, alc; slightly sol in ether. LC50 in rats, mice, dogs: 544 ppm (5 min), 169 ppm (30 min), 300 ppm (3 min) by inhalation, K. C. Back et al., Reclassification of Materials Listed as Transportation Health Hazards (TSA-20-72-3; PB214-270, 1972).
Melting point: mp -13.4°
Boiling point: bp 25.6°
Density: d(gas) 0.941 (air = 1); d(liq) 0.687
Toxicity data: LC50 in rats, mice, dogs: 544 ppm (5 min), 169 ppm (30 min), 300 ppm (3 min) by inhalation, K. C. Back et al., Reclassification of Materials Listed as Transportation Health Hazards (TSA-20-72-3; PB214-270, 1972)
CAUTION: Potential symptoms of acute overexposure are asphyxia; lassitude, headache, confusion; nausea, vomiting; increased rate and depth of respiration, or slow and gasping respiration. See NIOSH Pocket Guide to Chemical Hazards (PB2003-100121, 2003) p 168; Patty's Industrial Hygiene and Toxicology vol. 2D, G. D. Clayton, F. E. Clayton, Eds. (Wiley-Interscience, NewYork, 4th ed., 1994) pp 3119-3127.
Use: Compressed gas as rodenticide, and insect fumigant. |