- Formula: C2H2
- Molecular weight: 26.0373
- IUPAC Standard InChI:
- Download the identifier in a file.
- IUPAC Standard InChIKey: HSFWRNGVRCDJHI-UHFFFAOYSA-N
- CAS Registry Number: 74-86-2
- Chemical structure:
This structure is also available as a 2d Mol file or as a computed 3d SD file
- Other names: Ethyne; Ethine; Narcylen; C2H2; Acetylen; UN 1001; Vinylene
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Gas phase thermochemistry data
Go To: Top, References, Notes
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:
DRB - Donald R. Burgess, Jr.
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
GT - Glushko Thermocenter, Russian Academy of Sciences, Moscow
|fH°gas||54.190||kcal/mol||Review||Chase, 1998||Data last reviewed in March, 1961|
|fH°gas||54.3 ± 0.2||kcal/mol||Review||Manion, 2002||adopted recommendation of Gurvich, Veyts, et al., 1991; DRB|
|fH°gas||54.19 ± 0.19||kcal/mol||Ccb||Wagman, Kilpatrick, et al., 1945||Unpublished work of E. J. Prosen; ALS|
|S°gas,1 bar||48.023||cal/mol*K||Review||Chase, 1998||Data last reviewed in March, 1961|
Constant pressure heat capacity of gas
|Cp,gas (cal/mol*K)||Temperature (K)||Reference||Comment|
|7.015||100.||Gurvich, Veyts, et al., 1989||p=1 bar.; GT|
Gas Phase Heat Capacity (Shomate Equation)
Cp° = A + B*t + C*t2 + D*t3 +
H° − H°298.15= A*t + B*t2/2 + C*t3/3 + D*t4/4 − E/t + F − H
S° = A*ln(t) + B*t + C*t2/2 + D*t3/3 − E/(2*t2) + G
Cp = heat capacity (cal/mol*K)
H° = standard enthalpy (kcal/mol)
S° = standard entropy (cal/mol*K)
t = temperature (K) / 1000.
|Temperature (K)||298. - 1100.||1100. - 6000.|
|Reference||Chase, 1998||Chase, 1998|
|Comment||Data last reviewed in March, 1961||Data last reviewed in March, 1961|
Go To: Top, Gas phase thermochemistry data, Notes
Chase, M.W., Jr., NIST-JANAF Themochemical Tables, Fourth Edition, J. Phys. Chem. Ref. Data, Monograph 9, 1998, 1-1951. [all data]
Manion, J.A., Evaluated Enthalpies of Formation of the Stable Closed Shell C1 and C2 Chlorinated Hydrocarbons, J. Phys. Chem. Ref. Data, 2002, 31, 1, 123-172, https://doi.org/10.1063/1.1420703 . [all data]
Gurvich, Veyts, et al., 1991
Thermodynamic Properties of Individual Substances, 4th edition, Volume 2, Gurvich, L.V.; Veyts, I.V.; Alcock, C.B.;, ed(s)., Hemisphere, New York, 1991. [all data]
Wagman, Kilpatrick, et al., 1945
Wagman, D.D.; Kilpatrick, J.E.; Pitzer, K.S.; Rossini, F.D., Heats, equilibrium constants, and free energies of formation of the acetylene hydrocarbons through the pentynes, to 1,500° K, J. Res. NBS, 1945, 35, 467-496. [all data]
Gurvich, Veyts, et al., 1989
Gurvich, L.V.; Veyts, I.V.; Alcock, C.B., Thermodynamic Properties of Individual Substances, 4th ed.; Vols. 1 and 2, Hemisphere, New York, 1989. [all data]
Go To: Top, Gas phase thermochemistry data, References
- Symbols used in this document:
Cp,gas Constant pressure heat capacity of gas S°gas,1 bar Entropy of gas at standard conditions (1 bar) fH°gas Enthalpy of formation of gas at standard conditions
- Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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