2-Butynedioic acid
- Formula: C4H2O4
- Molecular weight: 114.0563
- IUPAC Standard InChI: InChI=1S/C4H2O4/c5-3(6)1-2-4(7)8/h(H,5,6)(H,7,8)
- IUPAC Standard InChIKey: YTIVTFGABIZHHX-UHFFFAOYSA-N
- CAS Registry Number: 142-45-0
- Chemical structure:
This structure is also available as a 2d Mol file or as a computed 3d SD file
View 3d structure (requires JavaScript / HTML 5) - Other names: Acetylenedicarboxylic acid; Butynedioic acid
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Phase change 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 by: Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| Tfus | 439.65 | K | N/A | Smith and Carlson, 1939 | Uncertainty assigned by TRC = 2.5 K |
Reaction 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 by: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
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Individual Reactions
2 +
=
By formula: 2H2 + C4H2O4 = C4H6O4
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | -363.2 ± 4.6 | kJ/mol | Chyd | Flitcroft and Skinner, 1958 | solid phase |
References
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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Smith and Carlson, 1939
Smith, L.I.; Carlson, E.J.,
Prehnitic Acid (Benzene-1,2,3,4-tetracroxylic Acid),
J. Am. Chem. Soc., 1939, 61, 288. [all data]
Flitcroft and Skinner, 1958
Flitcroft, T.L.; Skinner, H.A.,
Heats of hydrogenation Part 2.-Acetylene derivatives,
Trans. Faraday Soc., 1958, 54, 47-53. [all data]
Notes
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- Symbols used in this document:
Tfus Fusion (melting) point ΔrH° Enthalpy of reaction at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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