Home > Name List By a > acetylene

CAS No 74-86-2 , acetylene

  • Name: acetylene
  • Synonyms: 74-86-2;Ethyne;acetylene; Ethine; Acetylen; HSDB 166; ACETYLENE; Narcylen; Vinylene; Ethenylene; CHEBI:27518;
  • CAS Registry Number:
  • Transport: UN 1001
  • Melting Point: -88 ºC
  • Flash Point: -18 ºC
  • Boiling Point: -28 ºC
  • Density: 0.91
  • Refractive index: 1.00051
  • Water Solubility: 0.106 G/100 ML
  • Safety Statements: Mildly toxic by inhalation. Human systemic effects by inhalation: headache and dyspnea. Narcotic in high concentration. In general industrial practice, acetylene does not constitute a serious toxic hazard. It is a very dangerous fire hazard when exposed to heat, flame, or oxidizers. Moderate explosion hazard when exposed to heat or flame or by spontaneous chemical reaction. At high pressures and moderate temperatures, and in the absence of air, acetylene has been known to decompose explosively. Reacts with copper to form the explosive copper acetylide. Incompatible with brass, copper salts, copper carbide, powdered Co, Hg, Hg salts, K, Ag and Ag salts, RbH, CsH, halogens, HNO3, NaH, oxidants. Acetylene + halide + UV can explode. Molten K ignites in C2H2 and then explodes. C2H2 reacts vigorously with trifluoromethyl hypofluorite. With O2, C2H2 can detonate very powerfully. See ACETYLIDES. When ignited, it burns with an intensely hot flame; can react vigorously with oxidizing materials.When mixed with O2 in proportions of 40% or more, acetylene acts as a narcotic and has been used in anesthesia. Acetylene acts as a simple asphyxiant by diluting the O2 in the air to a level that will not support life. However, the presence of impurities in commercial acetylene may result in the production of symptoms before an asphyxiant concentration is reached. Thus: 10% in air produces a slight intoxication, 20% produces a staggering gait, 30% produces general incoordination, 33% leads to unconsciousness in 7 minutes, up to 80% produces complete anesthesia, increased blood pressure, narcosis, and stimulated respiration.Dizziness, headache, mild gastric symptoms, and (in high concentration) semi-asphyxia and brief loss of consciousness have all been reported. See ARGON for a discussion of simple asphyxiants. To fight fire, use CO2, water spray, or dry chemical. Stop flow of gas.
  • Hazard Symbols: F+: Highly flammable;
  • Flash Point: -18 ºC
  • EINECS: 200-816-9
  • Molecular Weight: 26.03728
  • InChI: InChI=1S/C2H2/c1-2/h1-2H
  • Risk Statements: 5-6-12
  • Molecular Formula: C2H2
  • Molecular Structure:CAS No:74-86-2 acetylene
References of acetylene
Title: Acetylene
CAS Registry Number: 74-86-2
CAS Name: Ethyne
Synonyms: ethine
Molecular Formula: C2H2
Molecular Weight: 26.04
Percent Composition: C 92.25%, H 7.74%
Line Formula: HCoCH
Literature References: Manuf from calcium carbide and water: Eastman, US 3017259 (1962 to Texaco); from methane: Anderson, US 3051639 (1962 to Union Carbide). Toxicity data: Riggs, Proc. Soc. Exp. Biol. Med. 22, 269 (1925). Review of manuf processes: Faith, Keyes & Clark's Industrial Chemicals, F. A. Lowenheim, M. K. Moran, Eds. (Wiley-Interscience, New York, 4th ed., 1975) pp 26-35. Review: Nieuwland, Vogt, The Chemistry of Acetylene (Reinhold, New York, 1945) pp 1-219. Comprehensive monograph in 2 vols: S. A. Miller, Acetylene (Academic Press, New York, 1965); several authors in Kirk-Othmer Encyclopedia of Chemical Technology vol. 1 (Wiley-Interscience, New York, 3rd ed., 1978) pp 192-243.
Properties: Gas; odor not unpleasant when pure, but disagreeable when impure (due to phosphine). mp -81° (subl). At 0° liquifies at 21.5 atm; below 37° (crit temp) liquifies at 68 atm. One liter at 0° and 760 mm weighs 1.165 g; d gas (air = 1) 0.90. Burns brilliantly in air with very sooty flame. Heat of combustion 313 cal. Not explosive at ordinary atmospheric pressure, but at 2 atms or more it is explosive by spark or decomposition. Mixture with air containing more than 3% or less than 65% gas is explosive, max being 1 vol gas and 12.5 vol air. Forms insoluble explosive compounds with copper and silver; hence copper or brass containers must be avoided. One vol dissolves in 1 vol water, in 6 vols glacial acetic acid or alcohol; soluble in ether, benzene. Acetone dissolves 25 vols acetylene at 15° and 760 mm; but 300 vols at 12 atm. LC in rats: 900000 ppm (Riggs).
Density: d gas (air = 1) 0.90
Toxicity data: LC in rats: 900000 ppm (Riggs)
CAUTION: Potential symptoms of overexposure are headache, dizziness; asphyxia; direct contact with liquid may cause frostbite. See NIOSH Pocket Guide to Chemical Hazards (DHHS/NIOSH 97-140, 1997) p 4.
Use: Illuminant, oxyacetylene welding, cutting, and soldering metals, signalling; pptg metals, particularly Cu; manuf acetaldehyde, acetic acid; fuel for motor boats.