Cyanic acid HCNO

The reaction of diacetylene with cyanic acid (HCNO) proceeds at room temperature in the presence of sulfuric acid in aqueous methanol to give 3-formyl-5,5 -diisoxazol-3 -aldoxime (85) and 3,3 -diformyl-5,5 -diisoxazoldioxime (86), whose oxidation with potassium permanganate followed by esterification results in 3,3 -dicarbomethoxy-5,5 -diisoxazoles (87) (59G598). 

C17-0063. For a 2.75 X 10 M aqueous solution of cyanic acid, HCNO, do the following (a) Identify the major and minor species, (b) Compute concentrations of all species present, (c) Find the pH. (d) Draw a molecular picture illustrating the equilibrium reaction that determines the pH. 

Feeding experiments showed that this reaction did not occur biologically nor, in contrast to the Wohler experiment, was ammonium cyanate converted to urea in the liver. Indeed cyanic acid, (HCNO), was very toxic. 

Fulminic acid C = NOH is a gaseous, highly toxic substance with an odour resembling that of hydrogen cyanide. It is isomeric with other acids cf the same empirical formula HCNO. The chief of these is cyanic acid HCNO, which is obtainable only in the form of its salts free cyanic acid is unstable. The action of inorganic acids on cyanates leads to the evolution of cyanic acid which hydrolyses to form carbon dioxide and ammonia ... 

CYANIC ACID AND RELATED COMPOUNDS. Cyanic acid. HCNO or HOCN, is a colorless, odorless liquid soluble in water and in ether volatile wilh decomposition when heated passing al ordinary temperature... 

There are the three famous isomers fulminic acid, cyanic acid, and isocyanic acid. Fulminic acid, HONC, is used to make the explosives that share their name with the verb to fulminate, meaning to verbally rage. Cyanic acid has the formula HOCN and is used to make poisonous cyanates. Isocyanic acid, HCNO, is less familiar because it calmly goes about its business as a starting material for making organic compounds and doesn t explode or poison you outright. 

As may be recalled from our discussion of the law of definite proportion, isomers are molecules that have been built from the same number and type of atoms but arranged in a different order. We cited, as examples, fulminic acid, cyanic acid, and isocyanic acid HONC, HOCN, and HCNO, respectively. We saw that this simple rearrangement of elements made the first explosive, the second a poison, and the third a pacific participant in several, more constructive, organic syntheses. Isomers that differ only by being mirror images of each other are termed chiral isomers (pronounced kiral, with a hard c sound, the way chemist is pronounced kemisf). 

Calculate the hydrogen ion (H+) concentration in a 0.1-M HCNO solution. What is the degree of ionization of cyanic acid in this same solution The ionization constant, K, for the acid is 2 x lO. ... 

We are now in a position to collect, for example, all the three constitutional isomers with molecular formula HCNO that were already mentioned. Here are the chemical notations of fulminic acid, cyanic acid and isocyanic acid ... 

Figure 47.4 Metabolic pathway of cyanide. The cyanide in the cells can be rapidly detoxified by cyanide sulfurtransferase (known as rhodanese). The majority of cyanide in vivo is enz5miatically converted to SCN and excreted in the urine. The remaining cyanide is metabolized mainly via two other routes (i) production of 2-amino-4-thiazolmecarboxylic add from cystine and cyanide, and (ii) synthesis of cyanocobalamin via the combination of cyanide with some other of vitamin B12 analogue, such as hydroxycobala-min or methylcobalamin (Boxer and Richards 1952). CN cyanide Na2S203 sodium thiosulfate SCN thiocyanate CN-B12 cyanocobalamin HCN hydrocyanic acid HCNO cyanic acid HCOOH formic acid.

Cyanic, HCNO.—Unstable liquid smell similar to acetic acid. 

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