- Sodium cyanide
Sodium cyanide Identifiers CAS number PubChem ChemSpider UN number 1689 ChEMBL RTECS number VZ7525000 Jmol-3D images Image 1 Properties Molecular formula NaCN Molar mass 49.0072 g/mol Appearance white solid Density 1.595 g/cm3 Melting point
Solubility in water 58 g/100 ml (20 °C) (hydrate solubility), 82 g/100 ml (34.7 °C) Refractive index (nD) 1.45 Hazards MSDS ICSC 1118 EU Index 006-007-00-5 EU classification Very toxic (T+)
Dangerous for the environment (N)Corrosive (C) 
R-phrases , , S-phrases , , , , , , NFPA 704 Flash point Non-flammable LD50 5.8–15 mg/kg (oral in rats, mice) Related compounds Other cations Potassium cyanide Related compounds Hydrogen cyanide (what is: /?)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Sodium cyanide is an inorganic compound with the formula NaCN. This highly toxic colorless salt is used mainly in gold mining but has other niche applications. It is an inorganic salt derived from neutralization reactions involving the weak acid hydrogen cyanide.
Production and chemical properties
- HCN + NaOH → NaCN + H2O
Worldwide production was estimated at 500,000 tons in the year 2006. In former times, it was prepared by the Castner-Kellner process involving the reaction of sodium amide with carbon at elevated temperatures.
- NaNH2 + C → NaCN + H2
The structure of solid NaCN is related to that of sodium chloride. The anions and cations are each six-coordinate (potassium chloride (KCN) has a similar structure). Each Na+ forms pi-bonds to two CN- groups as well as two "bent" Na---CN and two "bent" Na---NC links.
Because the salt is derived from a weak acid, NaCN readily reverts back to HCN by hydrolysis: the moist solid emits small amounts of hydrogen cyanide, which smells like bitter almonds (not everyone can smell it—the ability thereof is due to a genetic trait). Sodium cyanide reacts rapidly with strong acids to release hydrogen cyanide. This dangerous process represents a significant risk associated with cyanide salts. It is detoxified most efficiently with hydrogen peroxide (H2O2) to produce sodium cyanate (NaOCN) and water:
- NaCN + H2O2 → NaOCN + H2O
Sodium gold cyanide
Sodium cyanide is mainly used to extract gold and other precious metals in mining. This application exploits the high affinity of gold(I) for cyanide, which induces gold metal to oxidize and dissolve in the presence of air and water, producing the salt sodium gold cyanide (or gold sodium cyanide) and sodium hydroxide:
- 4 Au + 8 NaCN + O2 + 2 H2O → 4 Na[Au(CN)2] + 4 NaOH
A similar process uses potassium cyanide (KCN, a close relative of sodium cyanide) to produce potassium gold cyanide (KAu(CN2)).
Few other methods exist for this extraction process.
Several commercially significant chemical compounds are derived from cyanide, including cyanuric chloride, cyanogen chloride, and many nitriles. In organic synthesis, cyanide, which is classified as a strong nucleophile, is used to prepare nitriles, which occur widely in many specialty chemicals, including pharmaceuticals.
Being highly toxic, sodium cyanide is used to kill or stun rapidly such as in illegal cyanide fishing and in collecting jars used by entomologists.
Cyanide salts are among the most rapidly acting of all known poisons. Cyanide is a potent inhibitor of respiration, acting on mitochondrial cytochrome oxidase and hence blocking electron transport. This results in decreased oxidative metabolism and oxygen utilization. Lactic acidosis then occurs as a consequence of anaerobic metabolism.
- ^ Oxford MSDS
- ^ Martel, B.; Cassidy, K. (2004). Chemical Risk Analysis: A Practical Handbook. Butterworth–Heinemann. pp. 361. ISBN 1903996651.
- ^ a b Andreas Rubo, Raf Kellens, Jay Reddy, Norbert Steier, Wolfgang Hasenpusch "Alkali Metal Cyanides" in Ullmann's Encyclopedia of Industrial Chemistry 2006 Wiley-VCH, Weinheim, Germany. doi:10.1002/14356007.i01_i01
- ^ Wells, A.F. (1984) Structural Inorganic Chemistry, Oxford: Clarendon Press. ISBN 0-19-855370-6.
- ^ H. T. Stokes, D. L. Decker, H. M. Nelson, J. D. Jorgensen (1993). "Structure of potassium cyanide at low temperature and high pressure determined by neutron diffraction". Phys. Rev. B 47 (17): 11082–11092. doi:10.1103/PhysRevB.47.11082.
- ^ Online 'Mendelian Inheritance in Man' (OMIM) 304300
- Institut national de recherche et de sécurité (1997). "Cyanure de sodium. Cyanure de potassium". Fiche toxicologique n° 111, Paris:INRS, 6pp. (PDF file, in French)
- International Chemical Safety Card 1118
- Hydrogen cyanide and cyanides (CICAD 61)
- National Pollutant Inventory - Cyanide compounds fact sheet
- NIOSH Pocket Guide to Chemical Hazards
- EINECS number 205-599-4
- CID 8929 from PubChem
- CSST (Canada)
- Sodium cyanide hazards to fish and other wildlife from gold
NaAlO2 · NaBH3(CN) · NaBH4 · NaBr · NaBrO3 · NaCH3COO · NaCN · NaC6H5CO2 · NaC6H4(OH)CO2 · NaCl · NaClO · NaClO2 · NaClO3 · NaClO4 · NaF · NaH · NaHCO3 · NaHSO3 · NaHSO4 · NaI · NaIO3 · NaIO4 · NaMnO4 · NaNH2 · NaNO2 · NaNO3 · NaN3 · NaOH · NaO2 · NaPO2H2 · NaReO4 · NaSCN · NaSH · NaTcO4 · NaVO3 · Na2CO3 · Na2C2O4 · Na2CrO4 · Na2Cr2O7 · Na2MnO4 · Na2MoO4 · Na2O · Na2O2 · Na2O(UO3)2 · Na2S · Na2SO3 · Na2SO4 · Na2S2O3 · Na2S2O4 · Na2S2O5 · Na2S2O6 · Na2S2O7 · Na2S2O8 · Na2Se · Na2SeO3 · Na2SeO4 · Na2SiO3 · Na2Te · Na2TeO3 · Na2Ti3O7 · Na2U2O7 · NaWO4 · Na2Zn(OH)4 · Na3N · Na3P · Na3VO4 · Na4Fe(CN)6 · Na5P3O10 · NaBiO3
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Look at other dictionaries:
sodium cyanide — n. a white, highly poisonous salt, NaCN, used in electroplating, as an insecticide, etc … English World dictionary
sodium cyanide — natrio cianidas statusas T sritis chemija formulė NaCN atitikmenys: angl. sodium cyanide rus. натрий цианистый; натрия цианид … Chemijos terminų aiškinamasis žodynas
sodium cyanide — an extremely poisonous compound, NaCN, used for various industrial processes and to fumigate fruit trees. See also cyanide poisoning, under poisoning … Medical dictionary
sodium cyanide — noun a white poisonous salt (NaCN) used in electroplating • Hypernyms: ↑cyanide … Useful english dictionary
sodium cyanide — Chem. a white, crystalline, deliquescent, water soluble, poisonous powder, NaCN, prepared by heating sodium amide with charcoal: used chiefly in casehardening alloys, in the leaching and flotation of ore, and in electroplating. [1880 85] * * * … Universalium
sodium cyanide — noun Date: 1885 a white deliquescent poisonous salt NaCN used especially in electroplating, in fumigating, and in treating steel … New Collegiate Dictionary
sodium cyanide — so′dium cy′anide n. chem. a white, crystalline, water soluble, poisonous powder, NaCN, used chiefly in casehardening alloys, in the leaching and flotation of ore, and in electroplating • Etymology: 1880–85 … From formal English to slang
Cyanide poisoning — Classification and external resources Cyanide ion ICD 10 T … Wikipedia
Sodium nitroprusside — Sodium nitroprusside … Wikipedia
Cyanide fishing — is a method of collecting live fish mainly for use in aquariums, which involves spraying a sodium cyanide mixture into the desired fish s habitat in order to stun the fish. The practice hurts not only the target population, but also many other… … Wikipedia