F Hydrogen cyanide

Ethylmagnesium bromide, Water, 0847 Formic acid, 4436 f Hydrogen cyanide, 0380... 

Hydrochloric acid, see Hydrogen chloride, 3987 Hydrogen bromide, 0247 f Hydrogen cyanide, 0379a... 

Ethylmagnesium bromide, Water, 0843 Formic acid, 0417 f Hydrogen cyanide, 0379... 

Hydrogen cyanide (with the historical common name of Prussic acid) is a chemical compound with chemical formula HCN. Hydrogen cyanide is a colorless, extremely poisonous liquid that boils slightly above room temperature at 26 °C (79 °F). Hydrogen cyanide is a linear molecule, with a triple bond between carbon and nitrogen. A minor tautomer of HCN is HNC, hydrogen isocyanide. 

Figure 5.1 Principal inertial axes of (a) hydrogen cyanide, (b) methyl iodide, (c) benzene, (d) methane, (e) sulphur hexafluoride, (f) formaldehyde, (g) s-lraws-acrolein and (h) pyrazine...

This is not the case in most fires where some oi the intermediate produces, formed when large, complex molecules are broken up, persist. Examples are hydrogen cyanide from wool and silk, acrolein from vegetable oils, acetic acid from timber or paper, and carbon or carbon monoxide from the incomplete combustion of carbonaceous materials. As the fire develops and becomes hotter, many of these intermediates, which are often toxic, are destroyed—for example, hydrogen cyanide is decomposed at about 538°C (1000°F). 

Hydrogen cyanide Calcium cyanide Potassium cyanide Sodium cyanide Hydrogen fluoride as F Hydrogen peroxide Hydrogen selenide as Se Hydrogen sulphide Hydroquinone... 

Anhydrous hydrogen cyanide is a colorless or pale yellow liquid witli a mild odor similar lo lhal of biller almonds. The liquid boils at 78.3°F and 1,0 atm and forms a colorless, flanuiiablc, toxic gas. Hydrogen cyanide is completely... 

The upper layer which contains, in addition to acrylonitrile, hydrogen cyanide, acrolein, acetonitrile, and small quantities of other impurities, passes to a second reactor (E) where, at a suitable pH, all the acrolein is converted to its cyanohydrin. (Cyanohydrins are sometimes known as cyanhydrins.) The product from the reactor (E) is fed to a cyanohydrin separation column (F), operating at reduced temperature and pressure, in which acrolein cyanohydrin is separated as the bottom product and returned to the ammox-idation reactor (A) where it is quantitatively converted to acrylonitrile and hydrogen cyanide. 

The top product from column (F) is fed to a stripping column (G) from which hydrogen cyanide is removed overhead. 

Hydrogen cyanide is highly endothermic and of low MW (AH°f (g) +130.5 kJ/mol, 4.83 kJ/g). A comprehensive guide to all aspects of industrial handling of anhydrous hydrogen cyanide and its aqueous solutions states that the anhydrous liquid is stable at or below room temperature if it is inhibited with acid (e.g. 0.1% sulphuric acid) [ ] Presence of alkali favours explosive polymerisation [2], In absence of inhibitor, exothermic polymerisation occurs, and if the temperature attains 184°C, explosively rapid polymerisation occurs [3], A 100 g sample of 95-96% material stored in a glass bottle shielded from sunlight exploded after 8 weeks [4], The explosive polymerisation of a 33 kg cylinder was attributed to lack of sufficient phosphoric acid... 

James, B. R. Addition of Hydrogen and Hydrogen Cyanide to Carbon—Carbon Double and Triple Bonds. In Wilkinson, G. Stone, F. B. A. Abel, E. W., Eds., Comprehensive Organometallic Chemistry, Vol. 8, Pergamon, Oxford, 1982, Chapter 51. 

Levin, B.C. Paabo, M. Gurman, J.L. Clark, H.M. Yoklavich, M.F. Further Studies of the Toxicological Effects of Different Time Exposures to the Individual and Combined Fire Gases-Carbon Monoxide, Hydrogen Cyanide, Carbon Dioxide and Reduced Oxygen, Polyurethane 88. Proceedings of the 31— SPI Conference. Philadelphia, PA, 1988, p. 249-252. 

F-S [Ferrous sulfate] A process for removing ammonia, hydrogen sulfide, and hydrogen cyanide from coke-oven gas by scrubbing with aqueous ferrous sulfate solution obtained from steel pickling. A complex series of reactions in various parts of the absorption tower yield ammonium sulfate crystals and hydrogen sulfide (for conversion to sulfur or sulfuric acid) as the end products. Developed in Germany by F. J. Collin A.G. 

Howard, J.W., and R.F.Hanzal. 1955. Chronic toxicity to rats of food treated with hydrogen cyanide. Agric. Food Chem. 3 325-329. 

Weedon, F.R, A.Hartzell, and C.Setterstrom. 1940. Toxicity of ammonia, chlorine, hydrogen cyanide, hydrogen sulfide and sulfur dioxide gases. V. Animals. Contrib. Boyce Thompson Inst. 11 365-385. 

Bd Wt = body weight Cardio = cardiovascular d = day(s) DC so = concentration that resulted in 50% decrease in average respiratory rate EEG = electroencephalogram Endocr = endocrine F = female Gastro = gastrointestinal HCN = hydrogen cyanide Hemato = hematological LCso = lethal concentration, 50% kill LOAEL = lowest-observed-adverse-effect level M = male min = minutes NaCN = sodium cyanide NOAEL = no-observed-adverse-effect level NS = not specified (occup) = occupational Resp = respiratory sec = second(s) yr = year(s) x time(s)... 

Hexaazido-2,4,6-triaza-1,3,5-triphosphorine, 4795 Hydrogen azide, 4441 f Hydrogen selenide, 4486 f Hydrogen telluride, 4488 Iodoform, 0376 Lead(II) azide, 4782 Lead(IV) azide, 4790 Mercury(II) cyanide, 0976 Mercury(II) fulminate, 0978... 

The pyrolysis of pyrrole produces a variety of products hydrogen cyanide, propyne, allene, acetylene, c/ -crotonitrile, and allyl cyanide, among them. Lifshitz et al. hypothesized that pyrrole undergoes 1,2-bond (N—C) cleavage, then an internal H-atom transfer, to yield a radical intermediate that can isomerize to either c/ -crotonitrile or allyl cyanide, or dissociate to HCN and propyne.Bacskay et al. completed quantum chemical comparisons of the isoelectronic pyrrolyl and cyclopentadienyl radicals they hypothesized that pyrrolyl radical is formed via C—H bond scission in the intermediate pyrrolenine (2/f-pyrrole) rather than directly via N—H bond cleavage (Fig. 14). Mackie et al. explained a similar finding, postulating that it was the formation of pyrrolenine that dictated the rate at which pyrrole pyrolysis occurred. 

Schneider, J., V. Burger, and F. Arnold, Methyl Cyanide and Hydrogen Cyanide Measurements in the Lower Stratosphere Implications for Methyl Cyanide Sources and Sinks, . /. Geophys. Res., 102, 25501-25506 (1997). 

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