Ethylene oxide
- Formula: C2H4O
- Molecular weight: 44.0526
- IUPAC Standard InChI: InChI=1S/C2H4O/c1-2-3-1/h1-2H2
- IUPAC Standard InChIKey: IAYPIBMASNFSPL-UHFFFAOYSA-N
- CAS Registry Number: 75-21-8
- Chemical structure:
This structure is also available as a 2d Mol file or as a computed 3d SD file
The 3d structure may be viewed using Java or Javascript. - Other names: Oxirane; Dihydrooxirene; Dimethylene oxide; Epoxyethane; Ethene oxide; ETO; Oxacyclopropane; Oxane; Oxidoethane; Oxirene, dihydro-; Oxyfume; Oxyfume 12; T-Gas; 1,2-Epoxyethane; Aethylenoxid; Amprolene; Anprolene; Anproline; ENT-26263; E.O.; 1,2-Epoxyaethan; Ethyleenoxide; Etylenu tlenek; FEMA No. 2433; Merpol; NCI-C50088; α,β-Oxidoethane; Oxiraan; Oxiran; Rcra waste number U115; Sterilizing gas ethylene oxide 100%; UN 1040; Qazi-ketcham
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Condensed phase thermochemistry data
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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Data compiled as indicated in comments:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DH - Eugene S. Domalski and Elizabeth D. Hearing
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔfH°liquid | -22.88 ± 0.30 | kcal/mol | Ccb | Moureu and Dode, 1937 | Reanalyzed by Cox and Pilcher, 1970, Original value = -22.8 kcal/mol; ALS |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔcH°liquid | -301.85 ± 0.30 | kcal/mol | Ccb | Moureu and Dode, 1937 | Reanalyzed by Cox and Pilcher, 1970, Original value = -302.0 kcal/mol; Corresponding ΔfHºliquid = -22.88 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS |
| Quantity | Value | Units | Method | Reference | Comment |
| S°liquid | 35.719 | cal/mol*K | N/A | Giauque and Gordon, 1949 | DH |
Constant pressure heat capacity of liquid
| Cp,liquid (cal/mol*K) | Temperature (K) | Reference | Comment |
|---|---|---|---|
| 20.77 | 285. | Giauque and Gordon, 1949 | T = 15 to 283 K.; DH |
Reaction thermochemistry data
Go To: Top, Condensed phase thermochemistry data, References, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Data compiled by: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. A general reaction search form is also available. Future versions of this site may rely on reaction search pages in place of the enumerated reaction displays seen below.
Individual Reactions
=
+ 2
By formula: C16H35NO2 = C12H27N + 2C2H4O
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | -240.0 ± 6.5 | kcal/mol | Eqk | Balcerowiak, Jerzykiewicz, et al., 1984 | solid phase |
=
+
By formula: C14H31NO = C12H27N + C2H4O
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | -28.7 ± 1.1 | kcal/mol | Eqk | Balcerowiak, Jerzykiewicz, et al., 1984 | liquid phase |
References
Go To: Top, Condensed phase thermochemistry data, Reaction thermochemistry data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Moureu and Dode, 1937
Moureu, H.; Dode, M.,
Chaleurs de formation de l'oxyde d'ethylene, de l'ethanediol et de quelques homologues,
Bull. Soc. Chim. France, 1937, 4, 637-647. [all data]
Cox and Pilcher, 1970
Cox, J.D.; Pilcher, G.,
Thermochemistry of Organic and Organometallic Compounds, Academic Press, New York, 1970, 1-636. [all data]
Giauque and Gordon, 1949
Giauque, W.F.; Gordon, J.,
The entropy of ethylene oxide. Heat capacity from 14 to 285K. Vapor pressure. Heats of fusion and vaporization,
J. Am. Chem. Soc., 1949, 71, 2176-2181. [all data]
Balcerowiak, Jerzykiewicz, et al., 1984
Balcerowiak, W.; Jerzykiewicz, W.; Szewczyk, H.,
Differential thermal analysis using closed pans. The ethoxylation of n-dodecylamine,
Tenside Deterg., 1984, 21, 10-11. [all data]
Notes
Go To: Top, Condensed phase thermochemistry data, Reaction thermochemistry data, References
- Symbols used in this document:
Cp,liquid Constant pressure heat capacity of liquid S°liquid Entropy of liquid at standard conditions ΔcH°liquid Enthalpy of combustion of liquid at standard conditions ΔfH°liquid Enthalpy of formation of liquid at standard conditions ΔrH° Enthalpy of reaction at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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