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) Copy

  
• IUPAC Standard InChIKey: MUBZPKHOEPUJKR-UHFFFAOYSA-N Copy
• CAS Registry Number: 144-62-7
• Chemical structure:
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• 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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• Information on this page:
  • Gas phase thermochemistry data
  • Phase change data
  • Mass spectrum (electron ionization)
  • References
  • Notes
• Other data available:
  • Condensed phase thermochemistry data
  • Reaction thermochemistry data
  • Henry's Law data
  • Gas phase ion energetics data
  • UV/Visible spectrum
  • Gas Chromatography
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Gas 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 by: Glushko Thermocenter, Russian Academy of Sciences, Moscow

Constant pressure heat capacity of gas

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 as indicated in comments:
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
AC - William E. Acree, Jr., James S. Chickos
DH - Eugene S. Domalski and Elizabeth D. Hearing

Enthalpy of sublimation

Enthalpy of phase transition

Entropy of phase transition

Mass spectrum (electron ionization)

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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: NIST Mass Spectrometry Data Center, William E. Wallace, director

Spectrum

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Additional Data

References

Go To: Top, Gas phase thermochemistry data, Phase change data, Mass spectrum (electron ionization), Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Dorofeeva O.V., 1997
Dorofeeva O.V., Unpublished results. Thermocenter of Russian Academy of Science, Moscow, 1997. [all data]

Wilhoit and Shiao, 1964
Wilhoit, R.C.; Shiao, D., Thermochemistry of Biologically Important Compounds. Heats of Combustion of Solid Organic Acids, J. Chem. Eng. Data, 1964, 9, 595. [all data]

Bradley and Cleasby, 1953
Bradley, R.S.; Cleasby, T.G., The vapour pressure and lattice energy of hydrogen-bonded crystals. Part I. Oxamide, oxamic acid, and rubeanie acid, J. Chem. Soc., 1953, 1681-16. [all data]

Granovskaya, 1947
Granovskaya, A., Russ. J. Phys. Chem., 1947, 21, 967. [all data]

Noyes and Wobbe, 1926
Noyes, W. Albert; Wobbe, Delbert E., THE VAPOR PRESSURE OF ANHYDROUS OXALIC ACID, J. Am. Chem. Soc., 1926, 48, 7, 1882-1887, https://doi.org/10.1021/ja01418a012 . [all data]

Petropavlov, Tsygankova, et al., 1988
Petropavlov, N.N.; Tsygankova, I.G.; Teslenko, L.A., Microcalorimetric investigation of polymorphic transitions in organic crystals, Sov. Phys. Crystallogr., 1988, 33(6), 853-855. [all data]

Notes

Go To: Top, Gas phase thermochemistry data, Phase change data, Mass spectrum (electron ionization), References

• Symbols used in this document:
  

  Cp,gas	Constant pressure heat capacity of gas
  Tfus	Fusion (melting) point
  ΔHtrs	Enthalpy of phase transition
  ΔStrs	Entropy of phase transition
  ΔsubH	Enthalpy of sublimation
  ΔsubH°	Enthalpy of sublimation at standard conditions

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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