Acetic acid

Formula: C₂H₄O₂
Molecular weight: 60.0520
IUPAC Standard InChI: InChI=1S/C2H4O2/c1-2(3)4/h1H3,(H,3,4)
IUPAC Standard InChIKey: QTBSBXVTEAMEQO-UHFFFAOYSA-N
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
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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
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Information on this page:
Other data available:
- Gas phase thermochemistry data
- Condensed phase thermochemistry data
- Phase change data
- Reaction thermochemistry data: reactions 1 to 50
- Henry's Law data
- Gas phase ion energetics data
- Ion clustering data
- IR Spectrum
- Mass spectrum (electron ionization)
- 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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Reaction thermochemistry data

Go To: Top, References, Notes

Data compiled as indicated in comments:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
B - John E. Bartmess

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.

Reactions 51 to 79

+ = Acetic acid +

By formula: H₂O + C₆H₁₂OS = C₂H₄O₂ + C₄H₁₀S

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-12.6 ± 0.3	kJ/mol	Cm	Wadso, 1957	liquid phase; Heat of hydrolysis; ALS

+ = + Acetic acid

By formula: C₄H₅N₃O + H₂O = C₂H₃N₃ + C₂H₄O₂

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-30.5 ± 0.3	kJ/mol	Cm	Wadso, 1960	solid phase; Heat of hydrolysis; ALS

+ = + Acetic acid

By formula: C₉H₈O₃S + H₂O = C₇H₆O₂S + C₂H₄O₂

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-24.5 ± 0.3	kJ/mol	Cm	Nelander, 1964	solid phase; Heat of hydrolysis; ALS

+ = + Acetic acid

By formula: C₈H₈O₂ + H₂O = C₆H₆O + C₂H₄O₂

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-28.7 ± 0.2	kJ/mol	Cm	Wadso, 1960, 2	liquid phase; Heat of hydrolysis; ALS

+ = + Acetic acid

By formula: H₂O + C₈H₈OS = C₆H₆S + C₂H₄O₂

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-12.4 ± 0.3	kJ/mol	Cm	Wadso, 1960, 2	liquid phase; Heat of hydrolysis; ALS

= 1-(1-methylethylidene)-1H-indene + Acetic acid

By formula: C₁₄H₁₆O₂ = 1-(1-methylethylidene)-1H-indene + C₂H₄O₂

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-50.7 ± 1.7	kJ/mol	Cm	Thibblin, 1983	liquid phase; solvent: Methanol; At 20°C; ALS

+ = Acetic acid +

By formula: C₉H₈O₄ + H₂O = C₂H₄O₂ + C₇H₆O₃

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-20.6 ± 0.3	kJ/mol	Cm	Nelander, 1964	solid phase; Heat of hydrolysis; ALS

+ = + Acetic acid

By formula: C₄H₈O₂ + H₂O = C₂H₆O + C₂H₄O₂

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	3.7 ± 0.2	kJ/mol	Cm	Wadso, 1958	liquid phase; Heat of hydrolysis; ALS

+ = Acetic acid +

By formula: C₆H₁₂O₂ + H₂O = C₂H₄O₂ + C₄H₁₀O

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	3.3 ± 0.2	kJ/mol	Cm	Wadso, 1958	liquid phase; Heat of hydrolysis; ALS

+ = Acetic acid +

By formula: C₅H₁₀O₂ + H₂O = C₂H₄O₂ + C₃H₈O

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	2.3 ± 0.2	kJ/mol	Cm	Wadso, 1958	liquid phase; Heat of Hydrolysis; ALS

+ = Acetic acid +

By formula: C₉H₈O₄ + H₂O = C₂H₄O₂ + C₇H₆O₃

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-27.2 ± 0.3	kJ/mol	Cm	Nelander, 1964	solid phase; Heat of hydrolysis; ALS

= 1-(1-methylethylidene)-1H-indene + Acetic acid

By formula: C₁₄H₁₆O₂ = 1-(1-methylethylidene)-1H-indene + C₂H₄O₂

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-42.7 ± 1.3	kJ/mol	Cm	Thibblin, 1983	liquid phase; solvent: Methanol; ALS

+ = Acetic acid +

By formula: H₂O + C₃H₆O₂ = C₂H₄O₂ + CH₄O

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	4.39	kJ/mol	Cm	Coon and Daniels, 1933	liquid phase; solvent: in HCl; ALS

+ Acetic acid = +

By formula: C₂H₆O + C₂H₄O₂ = C₄H₈O₂ + H₂O

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	16.6 ± 0.3	kJ/mol	Eqk	Halford and Brundage, 1942	gas phase; At 313 K; ALS

+ 2 = + 2 Acetic acid

By formula: C₄H₆O₃ + 2C₃H₆O₃ = C₆H₁₀O₅ + 2C₂H₄O₂

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	0.0	kJ/mol	Eqk	Utkin, Bogel'fer, et al., 1991	liquid phase; NMR; ALS

C₆H₁₁NO₃ + = + Acetic acid

By formula: C₆H₁₁NO₃ + H₂O = C₄H₉NO₂ + C₂H₄O₂

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-2.2 ± 0.3	kJ/mol	Cm	Wadso, 1962	liquid phase; ALS

C₃H₄O₅^- + + Acetic acid = C₃H₆O₆^-

By formula: C₃H₄O₅^- + H₂O + C₂H₄O₂ = C₃H₆O₆^-

Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	19.2 ± 0.84	kJ/mol	IMRE	Viidanoja, Reiner, et al., 2000	gas phase; B

C₂H₄NO₅^- + + Acetic acid = C₂H₆NO₆^-

By formula: C₂H₄NO₅^- + H₂O + C₂H₄O₂ = C₂H₆NO₆^-

Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	19.2 ± 0.84	kJ/mol	IMRE	Viidanoja, Reiner, et al., 2000	gas phase; B

+ = + Acetic acid

By formula: C₆H₁₁NO₂S + H₂O = C₄H₉NOS + C₂H₄O₂

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	7.3 ± 0.3	kJ/mol	Cm	Wadso, 1962	liquid phase; ALS

+ = + Acetic acid

By formula: C₆H₁₃NO + H₂O = C₄H₁₁N + C₂H₄O₂

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	55.2 ± 0.2	kJ/mol	Cm	Wadso, 1962, 2	liquid phase; ALS

2 Acetic acid = +

By formula: 2C₂H₄O₂ = C₄H₆O₃ + H₂O

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	63.7 ± 1.2	kJ/mol	Eqk	Knopp, Linnell, et al., 1962	liquid phase; ALS

+ = + Acetic acid

By formula: C₄H₆O₃ + C₆H₇N = C₈H₉NO + C₂H₄O₂

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-100.9 ± 0.3	kJ/mol	Cm	Wadso, 1962, 2	liquid phase; ALS

+ = + Acetic acid

By formula: C₇H₁₂O₃ + H₂O = C₅H₁₀O₂ + C₂H₄O₂

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	12.	kJ/mol	Eqk	Grigor'ev, Katsman, et al., 1981	liquid phase; ALS

+ Acetic acid = +

By formula: C₂H₃NO₄ + C₂H₄O₂ = C₄H₆O₃ + HNO₃

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	16.7	kJ/mol	Cm	Tsvetkov, Shmakov, et al., 1989	liquid phase; ALS

+ = + Acetic acid

By formula: C₄H₆O₃ + C₉H₁₃N₃O₅ = C₁₁H₁₅N₃O₆ + C₂H₄O₂

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-43.9	kJ/mol	Kin	Shatynski and Hanesian, 1993	solid phase; ALS

+ Acetic acid = C₂H₄NO₅^-

By formula: NO₃^- + C₂H₄O₂ = C₂H₄NO₅^-

Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	49.37 ± 0.84	kJ/mol	IMRE	Viidanoja, Reiner, et al., 1998	gas phase; B

+ Acetic acid = C₂H₄NO₄^-

By formula: NO₂^- + C₂H₄O₂ = C₂H₄NO₄^-

Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	51.04 ± 0.84	kJ/mol	IMRE	Viidanoja, Reiner, et al., 1998	gas phase; B

+ Acetic acid =

By formula: C₂H₂O + C₂H₄O₂ = C₄H₆O₃

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-87.5 ± 2.2	kJ/mol	Eqk	Blake, Davies, et al., 1971	gas phase; ALS

CO₃^- + Acetic acid = C₃H₄O₅^-

By formula: CO₃^- + C₂H₄O₂ = C₃H₄O₅^-

Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	47.28 ± 0.84	kJ/mol	IMRE	Viidanoja, Reiner, et al., 1998	gas phase; B

References

Go To: Top, Reaction thermochemistry data, Notes

Wadso, 1957
Wadso, I., The heats of hydrolysis of some alkyl thiolesters, Acta Chem. Scand., 1957, 11, 1745-1751. [all data]

Wadso, 1960
Wadso, I., Heats of hydrolysis of N-acetylated imidazole, 1,2,4-triazole and tetrazole, Acta Chem. Scand., 1960, 14, 903-908. [all data]

Nelander, 1964
Nelander, L., The heats of hydrolysis of aspirin, thioaspirin, and their p-analogues, Acta Chem. Scand., 1964, 18, 973-984. [all data]

Wadso, 1960, 2
Wadso, I., Heats of hydrolysis of phenyl acetate and phenyl thiolacetate, Acta Chem. Scand., 1960, 14, 561-565. [all data]

Thibblin, 1983
Thibblin, A., Microcalorimetry in kinetic studies of a complex reaction system, Chem. Scr., 1983, 22, 70-73. [all data]

Wadso, 1958
Wadso, I., The heats of hydrolysis of some alkyl acetates, Acta Chem. Scand., 1958, 12, 630-633. [all data]

Coon and Daniels, 1933
Coon, E.D.; Daniels, F., An isothermal calorimeter for slow reactions, J. Phys. Chem., 1933, 37, 1-12. [all data]

Halford and Brundage, 1942
Halford, J.O.; Brundage, D., The vapor phase esterification equilibrium, J. Am. Chem. Soc., 1942, 64, 36-40. [all data]

Utkin, Bogel'fer, et al., 1991
Utkin, A.Yu.; Bogel'fer, L.Ya.; Chimishkyan, A.L., Reversible reactions in the acidolysis of methyoxyacetic acid by acetic anhydride, Russ. J. Phys. Chem. (Engl. Transl.), 1991, 65, 1049-1059, In original 1974. [all data]

Wadso, 1962
Wadso, I., Heats of hydrolysis of acetates and thiolacetates in aqueous solution, Acta Chem. Scand., 1962, 16, 487-494. [all data]

Viidanoja, Reiner, et al., 2000
Viidanoja, J.; Reiner, T.; Kiendler, A.; Grimm, F.; Arnold, F., Laboratory investigations of negative ion molecule reactions of propionic, butyric, glyoxylic, pyruvic, and pinonic acids, Int. J. Mass Spectrom., 2000, 194, 1, 53-68, https://doi.org/10.1016/S1387-3806(99)00172-4 . [all data]

Wadso, 1962, 2
Wadso, I., Heats of aminolysis and hydrolysis of some N-acetyl compounds and of acetic anhydride, Acta Chem. Scand., 1962, 16, 471-478. [all data]

Knopp, Linnell, et al., 1962
Knopp, J.A.; Linnell, W.S.; Child, W.C., Jr., The thermodynamics of the thermal decomposition of acetic acid in the liquid phase, J. Phys. Chem., 1962, 66, 1513-1516. [all data]

Grigor'ev, Katsman, et al., 1981
Grigor'ev, A.A.; Katsman, E.A.; Bobrov, A.F.; Dan'ko, T.N.; Pinkhasik, E.V., Preparation of γ-acetopropyl alcohol, Sov. Chem. Ind. (Engl. Transl.), 1981, 967-972. [all data]

Tsvetkov, Shmakov, et al., 1989
Tsvetkov, V.G.; Shmakov, V.A.; Sopin, V.F.; Ivanov, A.V.; Ikonnikov, A.A.; Marchenko, G.N., Enthalpies of reaction of nitric acid with acetic and trifluoroacetic anhydrides, J. Gen. Chem. USSR, 1989, 59, 1220-1222. [all data]

Shatynski and Hanesian, 1993
Shatynski, J.J.; Hanesian, D., Adiabatic kinetic studies of the cytidine/acetic anhydride reaction by utilizing temperature versus time data, Ind. Eng. Chem. Res., 1993, 32, 594-599. [all data]

Viidanoja, Reiner, et al., 1998
Viidanoja, J.; Reiner, T.; Arnold, F., Laboratory Investigations of Negative Ion-Molecule Reactions of Formic and Acetic Acid., Int. J. Mass Spectrom., 1998, 181, 1-3, 31, https://doi.org/10.1016/S1387-3806(98)14151-9 . [all data]

Blake, Davies, et al., 1971
Blake, P.G.; Davies, H.H.; Speis, A., Reactions of keten. Part II. The thermodynamics of the gas-phase equilibrium: acetic acid + keten = acetic anhydride, J. Chem. Soc. B, 1971, 2050-2052. [all data]

Notes

Go To: Top, Reaction thermochemistry data, References

Symbols used in this document:

Δ_rG° Free energy of reaction at standard conditions

Δ_rH° Enthalpy of reaction at standard conditions
Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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Δ_rG°	Free energy of reaction at standard conditions
Δ_rH°	Enthalpy of reaction at standard conditions