Search results
Results From The WOW.Com Content Network
Sodium cyanide is a compound with the formula Na C N and the structure Na + − C≡N. It is a white, water-soluble solid. Cyanide has a high affinity for metals, which leads to the high toxicity of this salt. Its main application, in gold mining, also exploits its high reactivity toward metals. It is a moderately strong base.
Among the most toxic cyanides are hydrogen cyanide (HCN), sodium cyanide (NaCN), potassium cyanide (KCN), and calcium cyanide (Ca(CN) 2). The cyanide anion is an inhibitor of the enzyme cytochrome c oxidase (also known as aa 3), the fourth complex of the electron transport chain found in the inner membrane of the mitochondria of eukaryotic ...
The following chart shows the solubility of various ionic compounds in water at 1 atm pressure and room temperature (approx. 25 °C, 298.15 K). "Soluble" means the ionic compound doesn't precipitate, while "slightly soluble" and "insoluble" mean that a solid will precipitate; "slightly soluble" compounds like calcium sulfate may require heat to precipitate.
In gold mining, KCN forms the water-soluble salt potassium gold cyanide (or gold potassium cyanide) and potassium hydroxide from gold metal in the presence of oxygen (usually from the surrounding air) and water: 4 Au + 8 KCN + O 2 + 2 H 2 O → 4 K[Au(CN) 2] + 4 KOH. A similar process uses NaCN to produce sodium gold cyanide (NaAu(CN 2)).
Cyanogen is typically generated from cyanide compounds. One laboratory method entails thermal decomposition of mercuric cyanide: . 2 Hg(CN) 2 → (CN) 2 + Hg 2 (CN) 2 Or, one can combine solutions of copper(II) salts (such as copper(II) sulfate) with cyanides; an unstable copper(II) cyanide is formed which rapidly decomposes into copper(I) cyanide and cyanogen.
The compound is linear and polar, but it does not spontaneously ionize in water. It dissolves in both water and polar organic solvents. Cyanogen bromide can be prepared by oxidation of sodium cyanide with bromine, which proceeds in two steps via the intermediate cyanogen ((CN) 2): 2 NaCN + Br 2 → (CN) 2 + 2 NaBr (CN) 2 + Br 2 → 2 (CN)Br
In contact with water, it hydrolyses into hydrogen cyanamide which decomposes and liberates ammonia: [5] CaCN 2 + 3 H 2 O → 2 NH 3 + CaCO 3. It was used to produce sodium cyanide by fusing with sodium carbonate: CaCN 2 + Na 2 CO 3 + 2 C → 2 NaCN + CaO + 2 CO. Sodium cyanide is used in cyanide process in gold mining.
Sodium cyanate is isostructural with sodium fulminate, confirming the linear structure of the cyanate ion. [3] It is made industrially by heating a mixture of sodium carbonate and urea. [4] Na 2 CO 3 + 2 OC(NH 2) 2 → 2 NaNCO + CO 2 + 2 NH 3 + H 2 O. A similar reaction is used to make potassium cyanate. Cyanates are produced when cyanides are ...