hydrocyanic acid

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Related to hydrocyanic acid: prussic acid


 (H) [hi´dro-jen]
a chemical element, atomic number 1, atomic weight 1.00797. (See Appendix 6.) It exists as the mass 1 isotope (protium, or light or ordinary hydrogen), mass 2 isotope (deuterium, heavy hydrogen), and mass 3 isotope (tritium).
hydrogen cyanide an extremely poisonous colorless liquid or gas, HCN, a decomposition product of various naturally occurring glycosides and a common cause of cyanide poisoning. Inhalation of the gas can cause death within a minute. Called also hydrocyanic acid.
heavy hydrogen deuterium.
hydrogen ion concentration the degree of concentration of hydrogen ions (the acid element) in a solution. Its symbol is pH, and it expresses the degree to which a solution is acidic or alkaline. The pH range extends from 0 to 14, pH 7 being neutral, a pH of less than 7 indicating acidity, and one above 7 indicating alkalinity. See also acid-base balance.
hydrogen peroxide H2O2, an antiseptic with a mildly antibacterial action. A 3 per cent solution foams on touching skin or mucous membrane and appears to have a mechanical cleansing action.
hydrogen sulfide H2S, a poisonous gas with an offensive smell, released from decaying organic material, natural gas, petroleum, and sulfur deposits, and sometimes used as a chemical reagent.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

hy·dro·cy·an·ic ac·id (HCN),

(hī'drō-sī-an'ik as'id),
HCN; A colorless, toxic liquid, with the odor of bitter almonds, present in bitter almonds (amygdalin), the stones of peaches, plums, and other drupes, and laurel leaves; inhalation of 300 ppm causes death.
Farlex Partner Medical Dictionary © Farlex 2012
References in periodicals archive ?
Some components, such as acetone and hydrocyanic acid, do not present a symmetric emission with temperature because they have a different origin.
Sorghum is considered to be a good feed in ordinary conditions but when it's normal growth is constrained by drought (Fjell et al., 1991), or imbalanced soil nutrients, hydrocyanic acid (HCN) content may develop to such an extent that the toxic level may reach lethal level when fed to animals (Singh et al., 1983).
[1] Nonstandard abbreviations: HCN, hydrocyanic acid; ID GC/MS, isotope-dilution gas chromatography/mass spectrometry; and SIM, selected-ion monitoring.
HYDROCYANIC ACID: HCN is converted into a gas cloud which kills in seconds.
The 44 people who died from a fire in a building in Tokyo's Shinjuku Ward at the weekend are believed to have died in one to two minutes after inhaling carbon monoxide or hydrocyanic acid gas, investigators said Tuesday.
Furthermore, its discharge of hydrocyanic acid and other toxic gases when on fire has become a problem.
Hydrocyanic acid potentials in leaf blade tissue of eleven grain sorghum hybrids.
(It had also been used to execute prisoners in the United States since the 1920s.) When exposed, it releases hydrocyanic acid (or HCN, prussic acid) into the air.
It said no deaths from mechanical injuries were visible and all symptoms were characteristic of a chemical weapons attack, particularly choking agents and organophosphorus agents or hydrocyanic acid.
For estimation of hydrocyanic acid (HCN) production by Pseudomonas sp., a color change in the sodium picrate containing filter paper strip was observed from yellow to orange brown to dark brown (Bakker and Schippers 1987).
The lethal dose of hydrocyanic acid [HCN] taken by mouth is 0.5-3.3 mg/kg body weight [3, 4].