Ethylene oxide

Ethylene oxide, called oxirane by IUPAC, is an organic compound with the chemical formula C2H4O.[5]

Ethylene oxide
Ethylene oxide.svg
Ethylene-oxide-from-xtal-3D-balls.png
Other names Ethylene oxide
Dimethylene oxide
1,2-Epoxyethane
[3]-crown-1
Epoxide
Identifiers
Abbreviations EO, EtO
CAS number 75-21-8
PubChem 6354
EC number 200-849-9
KEGG D03474
MeSH Ethylene+Oxide
ChEBI CHEBI:27561
RTECS number KX2450000
SMILES C1CO1
Properties
Molecular formula C2H4O
Molar mass 44.052 g·mol−1[1]
Appearance Colorless gas
Odor Ether-like
Density 0.8821 g·cm−3[1]
Melting point

−112.46 °C, 161 K, -170 °F

Boiling point
Solubility in water Miscible
Vapor pressure 1.46 atm (20 °C)[2]
−30.5·10−6 cm3/mol[3]
Refractive index (nD) 1.3597 (589 nm)[1]
Dipole moment 1.94 D
Thermochemistry
Std enthalpy of
formation
ΔfHo298
−52.6 kJ·mol−1[4]
Standard molar
entropy
So298
242.5 J·mol−1·K−1[4]
Specific heat capacity, C 47.9 J·mol−1·K−1[4]
Hazards
EU classification Flammable F+ Toxic T
Carc. Cat. 1
Main hazards Carcinogen
Extremely flammable
NFPA 704

NFPA 704.svg

4
3
3
 
R-phrases Template:R45, Template:R46, R12, R23, R36/37/38
S-phrases S53, S45
Explosive limits 3 to 100%
U.S. Permissible
exposure limit (PEL)
TWA 1 ppm 5 ppm [15-minute excursion][2]
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)

Ethylene Oxide Media

References

  1. 1.0 1.1 1.2 Haynes, p. 3.430
  2. 2.0 2.1 NIOSH Pocket Guide to Chemical Hazards. "#0275". National Institute for Occupational Safety and Health (NIOSH).
  3. Haynes, p. 3.576
  4. 4.0 4.1 4.2 Haynes, p. 5.22
  5. Rebsdat, Siegfried and Mayer, Dieter (2005) "Ethylene Oxide" in Ullmann's Encyclopedia of Industrial Chemistry. Wiley-VCH, Weinheim. doi:10.1002/14356007.a10_117.