Acetic acid

• Formula: C₂H₄O₂
• Molecular weight: 60.0520
• IUPAC Standard InChI: InChI=1S/C2H4O2/c1-2(3)4/h1H3,(H,3,4) Copy

  
• IUPAC Standard InChIKey: QTBSBXVTEAMEQO-UHFFFAOYSA-N Copy
• CAS Registry Number: 64-19-7
• 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.
• Isotopologues:
  • Acetic acid-d4
• Other names: Ethanoic acid; Ethylic acid; Glacial acetic acid; Methanecarboxylic acid; Vinegar acid; CH3COOH; Acetasol; Acide acetique; Acido acetico; Azijnzuur; Essigsaeure; Octowy kwas; Acetic acid, glacial; Kyselina octova; UN 2789; Aci-jel; Shotgun; Ethanoic acid monomer; NSC 132953
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Condensed phase thermochemistry data
  • Phase change data
  • Gas phase ion energetics data
  • Mass spectrum (electron ionization)
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Reaction thermochemistry data: reactions 1 to 50, reactions 51 to 79
  • Henry's Law data
  • Ion clustering data
  • IR Spectrum
  • UV/Visible spectrum
  • Vibrational and/or electronic energy levels
  • Gas Chromatography
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
  • X-ray Photoelectron Spectroscopy Database, version 5.0
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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

Constant pressure heat capacity of liquid

Phase change data

Go To: Top, Condensed phase thermochemistry data, Gas phase ion energetics data, Mass spectrum (electron ionization), References, Notes

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
AC - William E. Acree, Jr., James S. Chickos
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DH - Eugene S. Domalski and Elizabeth D. Hearing

Enthalpy of vaporization

Enthalpy of vaporization

Δ_vapH = A exp(-αT_r) (1 − T_r)^β
    Δ_vapH = Enthalpy of vaporization (at saturation pressure) (kJ/mol)
    T_r = reduced temperature (T / T_c)

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Antoine Equation Parameters

log₁₀(P) = A − (B / (T + C))
    P = vapor pressure (bar)
    T = temperature (K)

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Enthalpy of sublimation

Enthalpy of fusion

Entropy of fusion

Enthalpy of phase transition

Entropy of phase transition

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 evaluated as indicated in comments:
HL - Edward P. Hunter and Sharon G. Lias
L - Sharon G. Lias

Data compiled as indicated in comments:
B - John E. Bartmess
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron
LL - Sharon G. Lias and Joel F. Liebman

View reactions leading to C₂H₄O₂⁺ (ion structure unspecified)

Ionization energy determinations

Appearance energy determinations

De-protonation reactions

 +  =

By formula: C₂H₃O₂^- + H⁺ = C₂H₄O₂

C₂H₃O₂^- +  =

By formula: C₂H₃O₂^- + H⁺ = C₂H₄O₂

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, Condensed phase thermochemistry data, Phase change data, Gas phase ion energetics 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.

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Lebedeva, N.D., Heats of combustion of monocarboxylic acids, Russ. J. Phys. Chem. (Engl. Transl.), 1964, 38, 1435-1437. [all data]

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Carson, A.S.; Skinner, H.A., 201. Carbon-halogen bond energies in the acetyl halides, J. Chem. Soc., 1949, 936-939. [all data]

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Martin, J.F.; Andon, R.J.L., Thermodynamic properties of organic oxygen compounds. Part LII. Molar heat capacity of ethanoic, propanoic, and butanoic acids, J. Chem. Thermodynam., 1982, 14, 679-688. [all data]

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Pickering, S.U., A comparison of some properties of acetic acid and its chloro- and bromo-derivatives, J. Chem. Soc., 1895, 67, 664-684. [all data]

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von Reis, M.A., Die specifische Wärme flüssiger organischer Verbindungen und ihre Beziehung zu deren Moleculargewicht, Ann. Physik [3], 1881, 13, 447-464. [all data]

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Martin and Andon, 1982, 2
Martin, J.F.; Andon, R.J.L., Thermodynamic properties of organic oxygen compounds. Part LII. Molar heat capacity of ethanoic, propanoic, and butanoic acids., J. Chem. Thermodyn., 1982, 14, 679-88. [all data]

Parks and Kelley, 1925, 2
Parks, G.S.; Kelley, K.K., Thermal Data on Organic Compounds II. The Heat Capacities of Five Organic Compounds. The Entropies and Free Energies of Some Homologous Series of Aliphatic Compounds, J. Am. Chem. Soc., 1925, 47, 2089-97. [all data]

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Ambrose, Ellender, et al., 1977
Ambrose, D.; Ellender, J.H.; Sprake, C.H.S.; Townsend, R., Thermo. Prop. of Org. Oxygen Compounds XLV. The Vapor Pressure of Acetic Acid, J. Chem. Thermodyn., 1977, 9, 735. [all data]

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Vandana and Teja, 1995
Vandana, V.; Teja, A.S., The critical temperatures and densities of acetic acid-water mixtures, Fluid Phase Equilib., 1995, 103, 113-18. [all data]

Verevkin, 2000
Verevkin, S.P., Measurement and Prediction of the Monocarboxylic Acids Thermochemical Properties, J. Chem. Eng. Data, 2000, 45, 5, 953-960, https://doi.org/10.1021/je990282m . [all data]

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Konicek and Wadso, 1970
Konicek, J.; Wadso, I., Enthalpies of vaporization of organic compounds. VII. Some carboxylic acids, Acta Chem. Scand., 1970, 24, 2612-26. [all data]

Konicek, Wadsö, et al., 1970
Konicek, Jiri; Wadsö, Ingemar; Munch-Petersen, J.; Ohlson, Ragnar; Shimizu, Akira, Enthalpies of Vaporization of Organic Compounds. VII. Some Carboxylic Acids., Acta Chem. Scand., 1970, 24, 2612-2616, https://doi.org/10.3891/acta.chem.scand.24-2612 . [all data]

Muñoz and Krähenbühl, 2001
Muñoz, Laura A.L.; Krähenbühl, M. Alvina, Isobaric Vapor Liquid Equilibrium (VLE) Data of the Systems n -Butanol + Butyric Acid and n -Butanol + Acetic Acid, J. Chem. Eng. Data, 2001, 46, 1, 120-124, https://doi.org/10.1021/je000033u . [all data]

Vercher, Vázquez, et al., 2001
Vercher, Ernesto; Vázquez, M. Isabel; Martínez-Andreu, Antoni, Isobaric Vapor-Liquid Equilibria for Water + Acetic Acid + Lithium Acetate, J. Chem. Eng. Data, 2001, 46, 6, 1584-1588, https://doi.org/10.1021/je010106p . [all data]

Stephenson and Malanowski, 1987
Stephenson, Richard M.; Malanowski, Stanislaw, Handbook of the Thermodynamics of Organic Compounds, 1987, https://doi.org/10.1007/978-94-009-3173-2 . [all data]

Dykyj, 1970
Dykyj, J., Petrochemica, 1970, 10, 2, 51. [all data]

Tamir, Dragoescu, et al., 1983
Tamir, Abraham; Dragoescu, Claudia; Apelblat, Alexander; Wisniak, Jaime, Heats of vaporization and vapor-liquid equilibria in associated solutions containing formic acid, acetic acid, propionic acid and carbon tetrachloride, Fluid Phase Equilibria, 1983, 10, 1, 9-42, https://doi.org/10.1016/0378-3812(83)80002-8 . [all data]

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McDonald, R.A.; Shrader, S.A.; Stull, D.R., Vapor Pressures and Freezing Points of Thirty Pure Organic Compounds., J. Chem. Eng. Data, 1959, 4, 4, 311-313, https://doi.org/10.1021/je60004a009 . [all data]

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Potter, Andrew E.; Ritter, H.L., The Vapor Pressure of Acetic Acid and Acetic-d ₃ Acid-d. The Liquid Density of Acetic-d ₃ Acid-d, J. Phys. Chem., 1954, 58, 11, 1040-1042, https://doi.org/10.1021/j150521a025 . [all data]

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Calis-Van Ginkel, C.H.D.; Calis, G.H.M.; Timmermans, C.W.M.; de Kruif, C.G.; Oonk, H.A.J., Enthalpies of sublimation and dimerization in the vapour phase of formic, acetic, propanoic, and butanoic acids, The Journal of Chemical Thermodynamics, 1978, 10, 11, 1083-1088, https://doi.org/10.1016/0021-9614(78)90082-4 . [all data]

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Domalski, Eugene S.; Hearing, Elizabeth D., Heat Capacities and Entropies of Organic Compounds in the Condensed Phase. Volume III, J. Phys. Chem. Ref. Data, 1996, 25, 1, 1, https://doi.org/10.1063/1.555985 . [all data]

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Meyer, J., Z. Phys. Chem., Stoechiom. Verwandtschaftsl., 1910, 72, 225. [all data]

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Hunter, E.P.; Lias, S.G., Evaluated Gas Phase Basicities and Proton Affinities of Molecules: An Update, J. Phys. Chem. Ref. Data, 1998, 27, 3, 413-656, https://doi.org/10.1063/1.556018 . [all data]

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Holmes, Fingas, et al., 1981
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Holmes, J.L.; Lossing, F.P., Thermochemistry and unimolecular reactions of ionized acetic acid and its enol in the gas phase., J. Am. Chem. Soc., 1980, 102, 3732. [all data]

Holmes and Lossing, 1980, 2
Holmes, J.L.; Lossing, F.P., Gas-phase heats of formation of keto and enol ions of carbonyl compounds., J. Am. Chem. Soc., 1980, 102, 1591. [all data]

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Vilesov, F.I., The photoionization of vapors of compounds whose molecules contain carbonyl groups, Dokl. Phys. Chem., 1960, 132, 521, In original 1332. [all data]

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Angel and Ervin, 2006
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Grabowski, J.J.; Cheng, X., Gas-Phase Formation of the Enolate Monoanion of Acetic Acid by Proton Abstraction, J. Am. Chem. Soc., 1989, 111, 8, 3106, https://doi.org/10.1021/ja00190a078 . [all data]

Notes

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

• Symbols used in this document:
  

  AE	Appearance energy
  Cp,liquid	Constant pressure heat capacity of liquid
  IE (evaluated)	Recommended ionization energy
  Pc	Critical pressure
  S°liquid	Entropy of liquid at standard conditions
  Tboil	Boiling point
  Tc	Critical temperature
  Tfus	Fusion (melting) point
  Ttriple	Triple point temperature
  ΔHtrs	Enthalpy of phase transition
  ΔStrs	Entropy of phase transition
  ΔcH°liquid	Enthalpy of combustion of liquid at standard conditions
  ΔfH°liquid	Enthalpy of formation of liquid at standard conditions
  ΔfusH	Enthalpy of fusion
  ΔfusS	Entropy of fusion
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions
  ΔsubH	Enthalpy of sublimation
  ΔvapH	Enthalpy of vaporization
  ΔvapH°	Enthalpy of vaporization at standard conditions
  ρc	Critical density

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