2-Butanone

• Formula: C₄H₈O
• Molecular weight: 72.1057
• IUPAC Standard InChI: InChI=1S/C4H8O/c1-3-4(2)5/h3H2,1-2H3 Copy

  
• IUPAC Standard InChIKey: ZWEHNKRNPOVVGH-UHFFFAOYSA-N Copy
• CAS Registry Number: 78-93-3
• 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: Butan-2-one; Butanone; Ethyl methyl ketone; Ketone, methyl ethyl; Methyl ethyl ketone; MEK; C2H5COCH3; Acetone, methyl-; Aethylmethylketon; 3-Butanone; Butanone 2; Ethyl methyl cetone; Ethylmethylketon; Ketone, ethyl methyl; Meetco; Methyl acetone; Metiletilchetone; Metyloetyloketon; Rcra waste number U159; UN 1193; 2-Oxobutane; 2-Butanal; 2-butanone (MEK; methyl ethyl ketone); 2-butanone (MEK)
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Gas phase thermochemistry data
  • Gas phase ion energetics data
  • Ion clustering data
  • Mass spectrum (electron ionization)
  • Vibrational and/or electronic energy levels
  • References
  • Notes
• Other data available:
  • Condensed phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data
  • Henry's Law data
  • IR Spectrum
  • Gas Chromatography
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
• Options:
  • Switch to calorie-based units

Data at NIST subscription sites:

• NIST / TRC Web Thermo Tables, "lite" edition (thermophysical and thermochemical data)
• NIST / TRC Web Thermo Tables, professional edition (thermophysical and thermochemical data)

NIST subscription sites provide data under the NIST Standard Reference Data Program, but require an annual fee to access. The purpose of the fee is to recover costs associated with the development of data collections included in such sites. Your institution may already be a subscriber. Follow the links above to find out more about the data in these sites and their terms of usage.

Gas phase thermochemistry data

Go To: Top, Gas phase ion energetics data, Ion clustering data, Mass spectrum (electron ionization), Vibrational and/or electronic energy levels, 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:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
GT - Glushko Thermocenter, Russian Academy of Sciences, Moscow

Constant pressure heat capacity of gas

Constant pressure heat capacity of gas

Gas phase ion energetics data

Go To: Top, Gas phase thermochemistry data, Ion clustering data, Mass spectrum (electron ionization), Vibrational and/or electronic energy levels, References, Notes

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

View reactions leading to C₄H₈O⁺ (ion structure unspecified)

Electron affinity determinations

Ionization energy determinations

Appearance energy determinations

De-protonation reactions

C₄H₇O^- +  =

By formula: C₄H₇O^- + H⁺ = C₄H₈O

C₄H₇O^- +  =

By formula: C₄H₇O^- + H⁺ = C₄H₈O

C₄H₇O^- +  =

By formula: C₄H₇O^- + H⁺ = C₄H₈O

Ion clustering data

Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, Mass spectrum (electron ionization), Vibrational and/or electronic energy levels, 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:
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
B - John E. Bartmess
RCD - Robert C. Dunbar

Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. Searches may be limited to ion clustering reactions. A general reaction search form is also available.

Clustering reactions

CH₆N⁺ +  = (CH₆N⁺ • )

By formula: CH₆N⁺ + C₄H₈O = (CH₆N⁺ • C₄H₈O)

Bond type: Hydrogen bonds of the type NH+-O between organics

Free energy of reaction

C₃H₉Sn⁺ +  = (C₃H₉Sn⁺ • )

By formula: C₃H₉Sn⁺ + C₄H₈O = (C₃H₉Sn⁺ • C₄H₈O)

Free energy of reaction

C₄H₉O⁺ +  = (C₄H₉O⁺ • )

By formula: C₄H₉O⁺ + C₄H₈O = (C₄H₉O⁺ • C₄H₈O)

Bond type: Hydrogen bonds of the type OH-O between organics

C₅H₁₁O⁺ +  = (C₅H₁₁O⁺ • )

By formula: C₅H₁₁O⁺ + C₄H₈O = (C₅H₁₁O⁺ • C₄H₈O)

Bond type: Hydrogen bonds of the type OH-O between organics

 +  = ( • )

By formula: Cl^- + C₄H₈O = (Cl^- • C₄H₈O)

 +  = ( • )

By formula: Mg⁺ + C₄H₈O = (Mg⁺ • C₄H₈O)

 +  = ( • )

By formula: NO^- + C₄H₈O = (NO^- • C₄H₈O)

 +  = ( • )

By formula: Na⁺ + C₄H₈O = (Na⁺ • C₄H₈O)

Mass spectrum (electron ionization)

Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, Ion clustering data, Vibrational and/or electronic energy levels, 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

Notice: This spectrum may be better viewed with a Javascript and HTML 5 enabled browser.

For Zoom

1.) Enter the desired X axis range (e.g., 100, 200)

2.) Check here for automatic Y scaling

3.) Press here to zoom

Additional Data

Vibrational and/or electronic energy levels

Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, Ion clustering 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 by: Takehiko Shimanouchi

Trans form     Symmetry:   C_s     Symmetry Number σ = 1

Source: Shimanouchi, 1972

Notes

References

Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, Ion clustering data, Mass spectrum (electron ionization), Vibrational and/or electronic energy levels, Notes

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

Chao and Zwolinski, 1976
Chao, J.; Zwolinski, B.J., Ideal gas thermodynamic properties of propanone and 2-butanone, J. Phys. Chem. Ref. Data, 1976, 5, 319-328. [all data]

Buckley and Herington, 1965
Buckley, E.; Herington, E.F.G., Equilibria in some secondary alcohol + hydrogen + ketone systems, Trans. Faraday Soc., 1965, 61, 1618-1625. [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]

Sinke and Oetting, 1964
Sinke, G.C.; Oetting, F.L., The chemical thermodynamic properties of methyl ethyl ketone, J. Phys. Chem., 1964, 68, 1354-1358. [all data]

Chao J., 1986
Chao J., Thermodynamic properties of key organic oxygen compounds in the carbon range C1 to C4. Part 2. Ideal gas properties, J. Phys. Chem. Ref. Data, 1986, 15, 1369-1436. [all data]

Sinke G.C., 1964
Sinke G.C., The chemical thermodynamic properties of methyl ethyl ketone, J. Phys. Chem., 1964, 68, 1354-1358. [all data]

Chao J., 1976
Chao J., Ideal gas thermodynamic properties of propanone and 2-butanone, J. Phys. Chem. Ref. Data, 1976, 5, 319-328. [all data]

Nickerson J.K., 1961
Nickerson J.K., The thermodynamic properties of the methyl ketone series, J. Phys. Chem., 1961, 65, 1037-1043. [all data]

von Geiseler G., 1973
von Geiseler G., The heat capacity and the heat of vaporization of isomeric butylmethylketones and propylacetates, Z. Phys. Chem. (Leipzig), 1973, 252, 170-176. [all data]

Vilcu R., 1975
Vilcu R., Determination of heat capacities of some alcohols and ketones in vapor phase, Rev. Roum. Chim., 1975, 20, 603-609. [all data]

Kabo G.J., 1995
Kabo G.J., Thermodynamic properties, conformation, and phase transitions of cyclopentanol, J. Chem. Thermodyn., 1995, 27, 953-967. [all data]

Bennewitz K., 1938
Bennewitz K., Molar heats of vapor organic compounds, Z. Phys. Chem. (Leipzig), 1938, B39, 126-144. [all data]

Hunter and Lias, 1998
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]

Desfrancois, Abdoul-Carime, et al., 1994
Desfrancois, C.; Abdoul-Carime, H.; Khelifa, N.; Schermann, J.P., Fork 1/r to 1/r2 Potentials: Electron Exchange between Rydberg Atoms and Polar Molecules, Phys. Rev. Lett., 1994, 73, 18, 2436, https://doi.org/10.1103/PhysRevLett.73.2436 . [all data]

Traeger, 1985
Traeger, J.C., Heat of formation for the propanoyl cation by photoionization mass spectrometry, Org. Mass Spectrom., 1985, 20, 223. [all data]

McAdoo and Hudson, 1983
McAdoo, D.J.; Hudson, C.E., The decompositions of metastable [C₄H₈O]⁺ ions and the [C₄H₈O]⁺ potential surface, Org. Mass Spectrom., 1983, 18, 466. [all data]

Traeger, McLouglin, et al., 1982
Traeger, J.C.; McLouglin, R.G.; Nicholson, A.J.C., Heat of formation for acetyl cation in the gas phase, J. Am. Chem. Soc., 1982, 104, 5318. [all data]

Hernandez, Masclet, et al., 1977
Hernandez, R.; Masclet, P.; Mouvier, G., Spectroscopie de photoelectrons d'aldehydes et de cetones aliphatiques, J. Electron Spectrosc. Relat. Phenom., 1977, 10, 333. [all data]

Mouvier and Hernandez, 1975
Mouvier, G.; Hernandez, R., Ionisation and appearance potentials of alkylketones, Org. Mass Spectrom., 1975, 10, 958. [all data]

Tam, Yee, et al., 1974
Tam, W.-C.; Yee, D.; Brion, C.E., Photoelectron spectra of some aldehydes and ketones, J. Electron Spectrosc. Relat. Phenom., 1974, 4, 77. [all data]

Potapov and Sorokin, 1972
Potapov, V.K.; Sorokin, V.V., Kinetic energies of products of dissociative photoionization of molecules. I. Aliphatic ketones and alcohols, Khim. Vys. Energ., 1972, 6, 387. [all data]

Cocksey, Eland, et al., 1971
Cocksey, B.J.; Eland, J.H.D.; Danby, C.J., The effect of alkyl substitution on ionisation potential, J. Chem. Soc., 1971, (B), 790. [all data]

Dewar and Worley, 1969
Dewar, M.J.S.; Worley, S.D., Photoelectron spectra of molecules. I. Ionization potentials of some organic molecules and their interpretation, J. Chem. Phys., 1969, 50, 654. [all data]

Murad and Inghram, 1964
Murad, E.; Inghram, M.G., Photoionization of aliphatic ketones, J. Chem. Phys., 1964, 40, 3263. [all data]

Watanabe, Nakayama, et al., 1962
Watanabe, K.; Nakayama, T.; Mottl, J., Ionization potentials of some molecules, J. Quant. Spectry. Radiative Transfer, 1962, 2, 369. [all data]

Vilesov, 1960
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]

Hurzeler, Inghram, et al., 1958
Hurzeler, H.; Inghram, M.G.; Morrison, J.D., Photon impact studies of molecules using a mass spectrometer, J. Chem. Phys., 1958, 28, 76. [all data]

Vilesov and Terenin, 1957
Vilesov, F.I.; Terenin, A.N., The photoionization of the vapors of certain organic compounds, Dokl. Akad. Nauk SSSR, 1957, 115, 744, In original 539. [all data]

Olivato, Guerrero, et al., 1984
Olivato, P.R.; Guerrero, S.A.; Modelli, A.; Granozzi, G.; Jones, D.; Distefano, G., Electronic interaction in heterosubstituted acetones studied by means of ultraviolet photoelectron and electron transmission spectroscopy, J. Chem. Soc. Perkin Trans. 2, 1984, 1505. [all data]

Benoit and Harrison, 1977
Benoit, F.M.; Harrison, A.G., Predictive value of proton affinity. Ionization energy correlations involving oxygenated molecules, J. Am. Chem. Soc., 1977, 99, 3980. [all data]

Kimura, Katsumata, et al., 1975
Kimura, K.; Katsumata, S.; Yamazaki, T.; Wakabayashi, H., UV photoelectron spectra and sum rule consideration; out-of-plane orbitals of unsaturated compounds with planar-skeleton structure, J. Electron Spectrosc. Relat. Phenom., 1975, 6, 41. [all data]

Potzinger and Bunau, 1969
Potzinger, P.; Bunau, G.v., Empirische Beruksichtigung von Uberschussenergien bei der Auftrittspotentialbestimmung, Ber. Bunsen-Ges. Phys. Chem., 1969, 73, 466. [all data]

Murad and Inghram, 1964, 2
Murad, E.; Inghram, M.G., Thermodynamic properties of the acetyl radical and bond dissociation energies in aliphatic carbonyl compounds, J. Chem. Phys., 1964, 41, 404. [all data]

Chyall, Brickhouse, et al., 1994
Chyall, L.J.; Brickhouse, M.D.; Schnute, M.E.; Squires, R.R., Kinetic versus thermodynamic control in the deprotonation of unsymmetrical ketones in the gas phase, J. Am. Chem. Soc., 1994, 116, 19, 8681, https://doi.org/10.1021/ja00098a031 . [all data]

Zimmerman, Reed, et al., 1977
Zimmerman, A.H.; Reed, K.J.; Brauman, J.I., Photodetachment of electrons from enolate anions. Gas phase electron affinities of enolate radicals, J. Am. Chem. Soc., 1977, 99, 7203. [all data]

Graul and Squires, 1990
Graul, S.T.; Squires, R.R., Gas-Phase Acidities Derived from Threshold Energies for Activated Reactions, J. Am. Chem. Soc., 1990, 112, 7, 2517, https://doi.org/10.1021/ja00163a007 . [all data]

Graul and Squires, 1988
Graul, S.T.; Squires, R.R., On the Existence of Alkyl Carbanions in the Gas Phase, J. Am. Chem. Soc., 1988, 110, 2, 607, https://doi.org/10.1021/ja00210a054 . [all data]

Cumming and Kebarle, 1978
Cumming, J.B.; Kebarle, P., Summary of gas phase measurements involving acids AH. Entropy changes in proton transfer reactions involving negative ions. Bond dissociation energies D(A-H) and electron affinities EA(A), Can. J. Chem., 1978, 56, 1. [all data]

Meot-Ner, 1984
Meot-Ner, (Mautner)M., The Ionic Hydrogen Bond and Ion Solvation. 1. -NH+ O-, -NH+ N- and -OH+ O- Bonds. Correlations with Proton Affinity. Deviations Due to Structural Effects, J. Am. Chem. Soc., 1984, 106, 5, 1257, https://doi.org/10.1021/ja00317a015 . [all data]

Stone and Splinter, 1984
Stone, J.A.; Splinter, D.E., A high-pressure mass spectrometric study of the binding of (CH₃)₃Sn⁺ to lewis bases in the gas phase, Int. J. Mass Spectrom. Ion Processes, 1984, 59, 169. [all data]

Larson and McMahon, 1982
Larson, J.W.; McMahon, T.B., Formation, Thermochemistry, and Relative Stabilities of Proton - Bound dimers of Oxygen n - Donor Bases from Ion Cyclotron Resonance Solvent - Exchange Equilibria Measurements, J. Am. Chem. Soc., 1982, 104, 23, 6255, https://doi.org/10.1021/ja00387a016 . [all data]

Grimsrud and Kebarle, 1973
Grimsrud, E.P.; Kebarle, P., Gas Phase Ion Equilibria Studies of the Solvation of the Hydrogen Ion by Methanol, Dimethyl Ether and Water. Effect of Hydrogen Bonding, J. Am. Chem. Soc., 1973, 95, 24, 7939, https://doi.org/10.1021/ja00805a002 . [all data]

Lias, Liebman, et al., 1984
Lias, S.G.; Liebman, J.F.; Levin, R.D., Evaluated gas phase basicities and proton affinities of molecules heats of formation of protonated molecules, J. Phys. Chem. Ref. Data, 1984, 13, 695. [all data]

Keesee and Castleman, 1986
Keesee, R.G.; Castleman, A.W., Jr., Thermochemical data on Ggs-phase ion-molecule association and clustering reactions, J. Phys. Chem. Ref. Data, 1986, 15, 1011. [all data]

Larson and McMahon, 1984
Larson, J.W.; McMahon, T.B., Hydrogen bonding in gas phase anions. An experimental investigation of the interaction between chloride ion and bronsted acids from ICR chloride exchange equilibria, J. Am. Chem. Soc., 1984, 106, 517. [all data]

Larson and McMahon, 1984, 2
Larson, J.W.; McMahon, T.B., Gas phase negative ion chemistry of alkylchloroformates, Can. J. Chem., 1984, 62, 675. [all data]

Operti, Tews, et al., 1988
Operti, L.; Tews, E.C.; Freiser, B.S., Determination of Gas-Phase Ligand Binding Energies to Mg+ by FTMS Techniques, J. Am. Chem. Soc., 1988, 110, 12, 3847, https://doi.org/10.1021/ja00220a020 . [all data]

Reents and Freiser, 1981
Reents, W.D.; Freiser, B.S., Gas-Phase Binding Energies and Spectroscopic Properties of NO+ Charge-Transfer Complexes, J. Am. Chem. Soc., 1981, 103, 2791. [all data]

Farid and McMahon, 1978
Farid, R.; McMahon, T.B., Gas-Phase Ion-Molecule Reactions of Alkyl Nitrites by Ion Cyclotron Resonance Spectroscopy, Int. J. Mass Spectrom. Ion Phys., 1978, 27, 2, 163, https://doi.org/10.1016/0020-7381(78)80037-0 . [all data]

Moision and Armentrout, 2002
Moision, R.M.; Armentrout, P.B., Experimental and Theoretical Dissection of Sodium Cation/Glycine Interactions, J. Phys. Chem A, 2002, 106, 43, 10350, https://doi.org/10.1021/jp0216373 . [all data]

Shimanouchi, 1972
Shimanouchi, T., Tables of Molecular Vibrational Frequencies Consolidated Volume I, National Bureau of Standards, 1972, 1-160. [all data]

Notes

Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, Ion clustering data, Mass spectrum (electron ionization), Vibrational and/or electronic energy levels, References

• Symbols used in this document:
  

  AE	Appearance energy
  Cp,gas	Constant pressure heat capacity of gas
  EA	Electron affinity
  IE (evaluated)	Recommended ionization energy
  T	Temperature
  ΔfH°gas	Enthalpy of formation of gas at standard conditions
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions
  ΔrS°	Entropy of reaction at standard conditions

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
• The National Institute of Standards and Technology (NIST) uses its best efforts to deliver a high quality copy of the Database and to verify that the data contained therein have been selected on the basis of sound scientific judgment. However, NIST makes no warranties to that effect, and NIST shall not be liable for any damage that may result from errors or omissions in the Database.
• Customer support for NIST Standard Reference Data products.