Oxalic acid
- Formula: C2H2O4
- Molecular weight: 90.0349
- IUPAC Standard InChI: InChI=1S/C2H2O4/c3-1(4)2(5)6/h(H,3,4)(H,5,6)
- IUPAC Standard InChIKey: MUBZPKHOEPUJKR-UHFFFAOYSA-N
- CAS Registry Number: 144-62-7
- 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: Ethanedioic acid; Aktisal; Aquisal; Oxiric acid; HOOCCOOH; Acide oxalique; Acido ossalico; Ethanedionic acid; Kyselina stavelova; NCI-C55209; Oxaalzuur; Oxalsaeure; Ethane-1,2-dioic acid; NSC 62774
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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 as indicated in comments:
B - John E. Bartmess
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
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Individual Reactions
C2HO4- + =
By formula: C2HO4- + H+ = C2H2O4
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 324.2 ± 2.0 | kcal/mol | CIDC | Kumar, Prabhakar, et al., 2005 | gas phase; B |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrG° | 316.3 ± 2.0 | kcal/mol | CIDC | Kumar, Prabhakar, et al., 2005 | gas phase; B |
+ 2
=
+ 2
By formula: C4H6O4 + 2H2O = C2H2O4 + 2CH4O
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 4.165 ± 0.016 | kcal/mol | Cm | Anthoney, Finch, et al., 1975 | solid phase; solvent: Water; Hydrolysis; ALS |
References
Go To: Top, Reaction thermochemistry data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Kumar, Prabhakar, et al., 2005
Kumar, M.R.; Prabhakar, S.; Nagaveni, V.; Vairamani, M.,
Estimation of gas-phase acidities of a series of dicarboxylic acids by the kinetic method,
Rapid Commun. Mass Spectrom., 2005, 19, 8, 1053-1057, https://doi.org/10.1002/rcm.1888
. [all data]
Anthoney, Finch, et al., 1975
Anthoney, M.E.; Finch, A.; Stephens, M.,
The solution of dimethyl oxalate and oxalic acid in water and alkali. Standard enthalpy of formation of dimethyl oxalate,
Thermochim. Acta, 1975, 12, 427-431. [all data]
Notes
Go To: Top, Reaction thermochemistry data, References
- Symbols used in this document:
ΔrG° Free energy of reaction at standard conditions ΔrH° Enthalpy of reaction at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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