- Formula: C2H
- Molecular weight: 25.0293
- IUPAC Standard InChI:
- Download the identifier in a file.
- IUPAC Standard InChIKey: XEHVFKKSDRMODV-UHFFFAOYSA-N
- CAS Registry Number: 2122-48-7
- Chemical structure:
This structure is also available as a 2d Mol file or as a computed 3d SD file
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Gas phase thermochemistry data
Go To: Top, Reaction thermochemistry data, References, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
|fH°gas||476.98||kJ/mol||Review||Chase, 1998||Data last reviewed in March, 1967|
|fH°gas||556. ± 8.||kJ/mol||N/A||Tsang, 1996|
|S°gas,1 bar||207.44||J/mol*K||Review||Chase, 1998||Data last reviewed in March, 1967|
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 (J/mol*K)
H° = standard enthalpy (kJ/mol)
S° = standard entropy (J/mol*K)
t = temperature (K) / 1000.
|Temperature (K)||298. - 1200.||1200. - 6000.|
|Reference||Chase, 1998||Chase, 1998|
|Comment||Data last reviewed in March, 1967||Data last reviewed in March, 1967|
Reaction thermochemistry data
Go To: Top, Gas phase thermochemistry data, References, Notes
Data compiled by: John E. Bartmess
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.
(C2H2- 4294967295) + = C2H2-
By formula: (C2H2- 4294967295C2H) + C2H = C2H2-
|rH°||328. ± 15.||kJ/mol||N/A||Ervin, Gronert, et al., 1990||gas phase; Vinylidene neutral: «DELTA»Hf<=99±2 kcal, Kiefer, Sidhu, et al., 1989|
|rH°||187. ± 14.||kJ/mol||Ther||Guo and Grabowski, 1990||gas phase; Between PhF, Me3P|
Go To: Top, Gas phase thermochemistry data, Reaction 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]
Tsang, W., Heats of Formation of Organic Free Radicals by Kinetic Methods in Energetics of Organic Free Radicals, Martinho Simoes, J.A.; Greenberg, A.; Liebman, J.F., eds., Blackie Academic and Professional, London, 1996, 22-58. [all data]
Ervin, Gronert, et al., 1990
Ervin, K.M.; Gronert, S.; Barlow, S.E.; Gilles, M.K.; Harrison, A.G.; Bierbaum, V.M.; DePuy, C.H.; Lin, W.C., Bonds Strengths of Ethylene and Acetylene, J. Am. Chem. Soc., 1990, 112, 15, 5750, https://doi.org/10.1021/ja00171a013 . [all data]
Kiefer, Sidhu, et al., 1989
Kiefer, J.H.; Sidhu, S.S.; Kumaran, S.S.; Irdan, E.A., RRKM Model of C2H4 Dissociation: Heat of Formation of Vinylidene, Chem. Phys. Lett., 1989, 159, 1, 32, https://doi.org/10.1016/S0009-2614(89)87448-2 . [all data]
Guo and Grabowski, 1990
Guo, Y.; Grabowski, J.J., Gas Phase Ion Chemistry of the Vinylidene Radical Anion and the Acidity of the Vinyl Radical, Int. J. Mass Spectrom. Ion Proc., 1990, 97, 3, 253, https://doi.org/10.1016/0168-1176(90)85003-K . [all data]
Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, References
- Symbols used in this document:
S°gas,1 bar Entropy of gas at standard conditions (1 bar) fH°gas Enthalpy of formation of gas at standard conditions rH° Enthalpy of reaction at standard conditions
- Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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