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Oxalic acid

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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

Cp,gas (J/mol*K) Temperature (K) Reference Comment
38.4050.Dorofeeva O.V., 1997p=1 bar.
45.04100.
54.32150.
65.10200.
85. ± 5.298.15
85.52300.
102.17400.
115.25500.
125.47600.
133.54700.
140.04800.
145.36900.
149.791000.
153.531100.
156.711200.
159.441300.
161.801400.
163.841500.

Condensed 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 as indicated in comments:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DH - Eugene S. Domalski and Elizabeth D. Hearing

Quantity Value Units Method Reference Comment
Deltafsolid-828.93 ± 0.46kJ/molCmBrown, 1969ALS
Deltafsolid-829.94 ± 0.96kJ/molCcbWilhoit and Shiao, 1964ALS
Quantity Value Units Method Reference Comment
Deltacsolid-242.9 ± 0.92kJ/molCcbWilhoit and Shiao, 1964Corresponding «DELTA»fsolid = -829.94 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS
Deltacsolid-253.5 ± 0.46kJ/molCcbVerkade, Hartman, et al., 1926Reanalyzed by Cox and Pilcher, 1970, Original value = -251. kJ/mol; See Verkade, Hartman, et al., 1924; Corresponding «DELTA»fsolid = -819.35 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS
Quantity Value Units Method Reference Comment
solid,1 bar115.6J/mol*KN/ALuff and Reed, 1982DH

Constant pressure heat capacity of solid

Cp,solid (J/mol*K) Temperature (K) Reference Comment
105.9298.15Luff and Reed, 1982T = 5 to 320 K.; DH
146.340.David, 1964T = 298 to 373 K. Mean value. T = uncertain.; DH
118.0323.Satoh and Sogabe, 1939T = 0 to 100°C. Mean value given.; DH
120.1298.1Parks, Kelley, et al., 1929Extrapolation below 90 K, 38.49 J/mol*K. Revision of previous data.; DH

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

Quantity Value Units Method Reference Comment
Tfus464.45KN/AWilhoit and Shiao, 1964, 2Uncertainty assigned by TRC = 1.5 K; TRC
Quantity Value Units Method Reference Comment
Deltasub97.906kJ/molVBradley and Cleasby, 1953ALS

Enthalpy of sublimation

DeltasubH (kJ/mol) Temperature (K) Method Reference Comment
61.8306.AGranovskaya, 1947Based on data from 292. - 320. K.; AC
90.6333. - 378.GSNoyes and Wobbe, 1926AC

Enthalpy of phase transition

DeltaHtrs (kJ/mol) Temperature (K) Initial Phase Final Phase Reference Comment
1.300393.2crystaline, IIcrystaline, IPetropavlov, Tsygankova, et al., 1988DH

Entropy of phase transition

DeltaStrs (J/mol*K) Temperature (K) Initial Phase Final Phase Reference Comment
3.3393.2crystaline, IIcrystaline, IPetropavlov, Tsygankova, et al., 1988DH

In addition to the Thermodynamics Research Center (TRC) data available from this site, much more physical and chemical property data is available from the following TRC products:


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

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.

Individual Reactions

C2HO4- + Hydrogen cation = Oxalic acid

By formula: C2HO4- + H+ = C2H2O4

Quantity Value Units Method Reference Comment
Deltar1356. ± 8.4kJ/molCIDCKumar, Prabhakar, et al., 2005gas phase; B
Quantity Value Units Method Reference Comment
Deltar1323. ± 8.4kJ/molCIDCKumar, Prabhakar, et al., 2005gas phase; B

Ethanedioic acid, dimethyl ester + 2Water = Oxalic acid + 2Methyl Alcohol

By formula: C4H6O4 + 2H2O = C2H2O4 + 2CH4O

Quantity Value Units Method Reference Comment
Deltar17.428 ± 0.065kJ/molCmAnthoney, Finch, et al., 1975solid phase; solvent: Water; Hydrolysis; ALS

Henry's Law 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: Rolf Sander

Henry's Law constant (water solution)

kH(T) = H exp(d(ln(kH))/d(1/T) ((1/T) - 1/(298.15 K)))
H = Henry's law constant for solubility in water at 298.15 K (mol/kg*bar)
d(ln(kH))/d(1/T) = Temperature dependence constant (K)

H (mol/kg*bar) d(ln(kH))/d(1/T) (K) Method Reference Comment
5.0×10+8 EN/AValue obtained by missing citation using the group contribution method.
7.0×10+6 XN/AValue given here as quoted by missing citation.

Gas phase ion energetics 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
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
LL - Sharon G. Lias and Joel F. Liebman

Ionization energy determinations

IE (eV) Method Reference Comment
11.20PEMcGlynn and Meeks, 1976Vertical value; LLK
11.20PEMeeks, Arnett, et al., 1975Vertical value; LLK
11.20PEArnett, Newkome, et al., 1974Vertical value; LLK

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
C2O2+17.4 ± 0.1H2O+OEIChen and Holmes, 1994LL

De-protonation reactions

C2HO4- + Hydrogen cation = Oxalic acid

By formula: C2HO4- + H+ = C2H2O4

Quantity Value Units Method Reference Comment
Deltar1356. ± 8.4kJ/molCIDCKumar, Prabhakar, et al., 2005gas phase; B
Quantity Value Units Method Reference Comment
Deltar1323. ± 8.4kJ/molCIDCKumar, Prabhakar, et al., 2005gas phase; B

Mass spectrum (electron ionization)

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Henry's Law data, Gas phase ion energetics data, UV/Visible spectrum, References, Notes

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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Mass spectrum
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Additional Data

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Owner NIST Mass Spectrometry Data Center
Collection (C) 2014 copyright by the U.S. Secretary of Commerce
on behalf of the United States of America. All rights reserved.
Origin Japan AIST/NIMC Database- Spectrum MS-NW-1856
NIST MS number 229396

All mass spectra in this site (plus many more) are available from the NIST/EPA/NIH Mass Spectral Library. Please see the following for information about the library and its accompanying search program.


UV/Visible spectrum

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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: Victor Talrose, Alexander N. Yermakov, Alexy A. Usov, Antonina A. Goncharova, Axlexander N. Leskin, Natalia A. Messineva, Natalia V. Trusova, Margarita V. Efimkina

Spectrum

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UVVis spectrum
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Additional Data

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Source Pestemer and Alslev-Klinker, 1949
Owner INEP CP RAS, NIST OSRD
Collection (C) 2007 copyright by the U.S. Secretary of Commerce
on behalf of the United States of America. All rights reserved.
Origin INSTITUTE OF ENERGY PROBLEMS OF CHEMICAL PHYSICS, RAS
Source reference RAS UV No. 9249
Instrument Quartz spectrograph
Melting point 189.5 dec
Boiling point sub 157

References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Henry's Law data, Gas phase ion energetics data, Mass spectrum (electron ionization), UV/Visible spectrum, 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]

Brown, 1969
Brown, M.A.H., The heats of formation of selected cyanide and oxalate compounds, Diss. Abstr., 1969, 29, 3696. [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, 595-599. [all data]

Verkade, Hartman, et al., 1926
Verkade, P.E.; Hartman, H.; Coops, J., Calorimetric researches. X. Heats of combustion of successive terms of homologous series: dicarboxylic acids of the oxalic acid series, Rec. Trav. Chim. Pays/Bas, 1926, 45, 373-393. [all data]

Cox and Pilcher, 1970
Cox, J.D.; Pilcher, G., Thermochemistry of Organic and Organometallic Compounds, Academic Press, New York, 1970, 1-636. [all data]

Verkade, Hartman, et al., 1924
Verkade, P.E.; Hartman, H.; Coops, J., Jr., Chemistry - The molecular heat of combustion of successive terms of homologous series, Kom. Med. Akad. Ueknschap. Proc., 1924, 27, 859-866. [all data]

Luff and Reed, 1982
Luff, B.B.; Reed, R.B., Low-temperature heat capacity and entropy of oxalic acid and of biuret, J. Chem. Eng. Data, 1982, 27, 290-292. [all data]

David, 1964
David, D.J., Determination of specific heat and heat of fusion by differential thermal analysis. Study of theory and operating parameters, Anal. Chem., 1964, 36, 2162-2166. [all data]

Satoh and Sogabe, 1939
Satoh, S.; Sogabe, T., The specific heats of some solid aliphatic acids and their ammonium salts and the atomic heat of nitrogen, Sci. Pap. Inst. Phys. Chem. Res. (Tokyo), 1939, 36, 97-105. [all data]

Parks, Kelley, et al., 1929
Parks, G.S.; Kelley, K.K.; Huffman, H.M., Thermal data on organic compounds. V. A revision of the entropies and free energies of nineteen organic compounds, J. Am. Chem. Soc., 1929, 51, 1969-1973. [all data]

Wilhoit and Shiao, 1964, 2
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]

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]

McGlynn and Meeks, 1976
McGlynn, S.P.; Meeks, J.L., Photoelectron spectra of carbonyls, carbonates, oxalates and esterification effects, J. Electron Spectrosc. Relat. Phenom., 1976, 8, 85. [all data]

Meeks, Arnett, et al., 1975
Meeks, J.L.; Arnett, J.F.; Larson, D.B.; McGlynn, S.P., Photoelectron spectroscopy of carbonyls. Urea, oxamide, oxalic acid and oxamic acid, J. Am. Chem. Soc., 1975, 97, 3905. [all data]

Arnett, Newkome, et al., 1974
Arnett, J.F.; Newkome, G.; Mattice, W.L.; McGlynn, S.P., Excited electronic states of the «alpha»-dicarbonyls, J. Am. Chem. Soc., 1974, 96, 4385. [all data]

Chen and Holmes, 1994
Chen, H.; Holmes, J.L., The generation of OC2O+ and OC2O and a study of ionized OC3O and C2O by tandem mass spectrometry, Int. J. Mass Spectrom. Ion Processes, 1994, 133, 111. [all data]

Pestemer and Alslev-Klinker, 1949
Pestemer, M.; Alslev-Klinker, A., Z. Elektrochem, 1949, 53, 387. [all data]


Notes

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Henry's Law data, Gas phase ion energetics data, Mass spectrum (electron ionization), UV/Visible spectrum, References