Ketene

• Formula: C₂H₂O
• Molecular weight: 42.0367
• IUPAC Standard InChI: InChI=1S/C2H2O/c1-2-3/h1H2 Copy

  
• IUPAC Standard InChIKey: CCGKOQOJPYTBIH-UHFFFAOYSA-N Copy
• CAS Registry Number: 463-51-4
• 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: Ethenone; Carbomethene; CH2CO; Keto-ethylene
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Reaction thermochemistry data
  • Gas phase ion energetics data
  • Mass spectrum (electron ionization)
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Phase change data
  • Ion clustering data
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
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Reaction thermochemistry data

Go To: Top, 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:
B - John E. Bartmess
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
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

(CAS Reg. No. 77213-00-4 • 4294967295) +  = CAS Reg. No. 77213-00-4

By formula: (CAS Reg. No. 77213-00-4 • 4294967295C₂H₂O) + C₂H₂O = CAS Reg. No. 77213-00-4

 +  = ( • )

By formula: F^- + C₂H₂O = (F^- • C₂H₂O)

C₂HO^- +  =

By formula: C₂HO^- + H⁺ = C₂H₂O

(C₂H₃O^- • 4294967295) +  = C₂H₃O^-

By formula: (C₂H₃O^- • 4294967295C₂H₂O) + C₂H₂O = C₂H₃O^-

(CAS Reg. No. 78944-68-0 • 4294967295) +  = CAS Reg. No. 78944-68-0

By formula: (CAS Reg. No. 78944-68-0 • 4294967295C₂H₂O) + C₂H₂O = CAS Reg. No. 78944-68-0

 +  =

By formula: HNaO + C₂H₂O = C₂H₃NaO₂

(CAS Reg. No. 64723-96-2 • 4294967295) +  = CAS Reg. No. 64723-96-2

By formula: (CAS Reg. No. 64723-96-2 • 4294967295C₂H₂O) + C₂H₂O = CAS Reg. No. 64723-96-2

(CAS Reg. No. 211040-82-3 • 4294967295) +  = CAS Reg. No. 211040-82-3

By formula: (CAS Reg. No. 211040-82-3 • 4294967295C₂H₂O) + C₂H₂O = CAS Reg. No. 211040-82-3

=  + 

By formula: C₄H₆O₂S = C₂H₂O + C₂H₄OS

(CAS Reg. No. 84148-57-2 • 4294967295) +  = CAS Reg. No. 84148-57-2

By formula: (CAS Reg. No. 84148-57-2 • 4294967295C₂H₂O) + C₂H₂O = CAS Reg. No. 84148-57-2

 +  =

By formula: C₂H₂O + C₂H₄O₂ = C₄H₆O₃

 +  =

By formula: C₂H₂O + C₄H₁₀O = C₆H₁₂O₂

 +  =

By formula: C₂H₂O + C₄H₁₀O = C₆H₁₂O₂

 +  =

By formula: C₂H₂O + C₄H₁₀O = C₆H₁₂O₂

 +  =

By formula: C₂H₂O + C₄H₁₀O = C₆H₁₂O₂

 +  =

By formula: C₂H₂O + C₃H₈O = C₅H₁₀O₂

 +  =

By formula: C₂H₂O + C₂H₄OS = C₄H₆O₂S

 +  =

By formula: C₂H₂O + C₂H₆O = C₄H₈O₂

 +  =

By formula: C₂H₂O + C₃H₈O = C₅H₁₀O₂

 +  =

By formula: C₂H₂O + CH₄O = C₃H₆O₂

Gas phase ion energetics data

Go To: Top, Reaction thermochemistry 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 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
MM - Michael M. Meot-Ner (Mautner)
LL - Sharon G. Lias and Joel F. Liebman
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 C₂H₂O⁺ (ion structure unspecified)

Proton affinity at 298K

Gas basicity at 298K

Ionization energy determinations

Appearance energy determinations

De-protonation reactions

C₂HO^- +  =

By formula: C₂HO^- + H⁺ = C₂H₂O

Mass spectrum (electron ionization)

Go To: Top, Reaction thermochemistry data, Gas phase ion energetics data, 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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Additional Data

References

Go To: Top, Reaction thermochemistry 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.

Marks, Brauman, et al., 1988
Marks, J.; Brauman, J.I.; Mead, R.D.; Lykke, K.R.; Lineberger, W.C., Spectroscopy and Dynamics of the Dipole Supported State of Acetyl Fluoride Enolate Anion, J. Chem. Phys., 1988, 88, 11, 6785, https://doi.org/10.1063/1.454424 . [all data]

Farid and McMahon, 1980
Farid, R.; McMahon, T.B., The gas phase acidities of fluorinated acetones. An ICR investigation of the role of fluorine substituents in the stabilization of planar carbanions, Can. J. Chem., 1980, 58, 2307. [all data]

Wenthold and Squires, 1995
Wenthold, P.G.; Squires, R.R., Bond dissociation energies of F2(-) and HF2(-). A gas-phase experimental and G2 theoretical study, J. Phys. Chem., 1995, 99, 7, 2002, https://doi.org/10.1021/j100007a034 . [all data]

Larson and McMahon, 1983
Larson, J.W.; McMahon, T.B., Strong hydrogen bonding in gas-phase anions. An ion cyclotron resonance determination of fluoride binding energetics to bronsted acids from gas-phase fluoride exchange equilibria measurements, J. Am. Chem. Soc., 1983, 105, 2944. [all data]

Arshadi, Yamdagni, et al., 1970
Arshadi, M.; Yamdagni, R.; Kebarle, P., Hydration of Halide Negative Ions in the Gas Phase. II. Comparison of Hydration Energies for the Alkali Positive and Halide Negative Ions, J. Phys. Chem., 1970, 74, 7, 1475, https://doi.org/10.1021/j100702a014 . [all data]

Oakes, Jones, et al., 1983
Oakes, J.M.; Jones, M.E.; Bierbaum, V.M.; Ellison, G.B., Photoelectron spectroscopy of CCO^- and HCCO^-, J. Phys. Chem., 1983, 87, 4810. [all data]

Bartmess, Scott, et al., 1979
Bartmess, J.E.; Scott, J.A.; McIver, R.T., Jr., The gas phase acidity scale from methanol to phenol, J. Am. Chem. Soc., 1979, 101, 6047. [all data]

Holmes and Lossing, 1982
Holmes, J.L.; Lossing, F.P., Heats of formation of the ionic and neutral enols of acetaldehyde and acetone, J. Am. Chem. Soc., 1982, 104, 2648. [all data]

Nimlos, Soderquist, et al., 1989
Nimlos, M.R.; Soderquist, J.A.; Ellison, G.B., Spectroscopy of CH3CO- and CH3CO, J. Am. Chem. Soc., 1989, 111, 20, 7675, https://doi.org/10.1021/ja00202a001 . [all data]

DePuy, Bierbaum, et al., 1985
DePuy, C.H.; Bierbaum, V.M.; Damrauer, R.; Soderquist, J.A., Gas-phase reactions of the acetyl anion, J. Am. Chem. Soc., 1985, 107, 3385. [all data]

Nuttall, Laufer, et al., 1971
Nuttall, R.L.; Laufer, A.H.; Kilday, M.V., The enthalpy of formation of ketene, J. Chem. Thermodyn., 1971, 3, 167-174. [all data]

Rice and Greenberg, 1934
Rice, F.O.; Greenberg, J., Ketene. III. Heat of formation and heat of reaction with alcohols, J. Am. Chem. Soc., 1934, 38, 2268-2270. [all data]

Taft, 1987
Taft, R.W., The Nature and Analysis of Substitutent Electronic Effects, Personal communication. See also Prog. Phys. Org. Chem., 1987, 16, 1. [all data]

Blake and Speis, 1974
Blake, P.G.; Speis, A., Reactions of keten. Part IV. Kinetics and thermodynamics of the gas-phase reaction: Thioacetic acid + keten = acetic Thioanhydride, J. Chem. Soc. Perkin Trans. 2, 1974, 1879-1881. [all data]

Grabowski and Cheng, 1989
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]

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]

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]

Bouchoux and Salpin, 1999
Bouchoux, J.; Salpin, J.Y., Re-evaluated gas-phase basicity and proton affinity data from the thermokinetic method, Rapid Com. Mass Spectrom., 1999, 13, 932. [all data]

Niu, Bai, et al., 1993
Niu, B.; Bai, Y.; Shirley, D.A., High resolution photoelectron spectroscopy and femtosecond intramolecular dynamics of H₂CCO⁺ and D₂CCO⁺, J. Chem. Phys., 1993, 99, 2520. [all data]

Vogt, Williamson, et al., 1978
Vogt, J.; Williamson, A.D.; Beauchamp, J.L., Properties and reactions of ketene in the gas phase by ion cyclotron resonance spectroscopy and photoionization mass spectrometry. Proton affinity, site specificity of protonation, and heat of formation of ketene, J. Am. Chem. Soc., 1978, 100, 3478. [all data]

Hall, Maier, et al., 1977
Hall, D.; Maier, J.P.; Rosmus, P., Electronic states of ketene radical cation, Chem. Phys., 1977, 24, 373. [all data]

Baker and Turner, 1969
Baker, C.; Turner, D.W., Photoelectron spectra of allene and keten; Jahn-Teller distortion in the ionisation of allene, Chem. Commun., 1969, 480. [all data]

Price, Teegan, et al., 1951
Price, W.C.; Teegan, J.P.; Walsh, A.D., The absorption spectrum of ketene in the far ultra-violet, J. Chem. Soc., 1951, 920. [all data]

Bock, Hirabayashi, et al., 1981
Bock, H.; Hirabayashi, T.; Mohmand, S., Thermische erzeugung von alkyl- und halogenketenen, Chem. Ber., 1981, 114, 2595. [all data]

Bock, Hirabayashi, et al., 1977
Bock, H.; Hirabayashi, T.; Mohmand, S.; Solouki, B., Instabile Zwischenprodukte in der Gasphase: Der thermische Zerfall von Carbonsaurechloriden RCOCl, Angew. Chem., 1977, 89, 106. [all data]

Collin and Locht, 1970
Collin, J.E.; Locht, R., Positive and negative ion formation in ketene by electron impact, Intern. J. Mass Spectrom. Ion Phys., 1970, 3, 465. [all data]

McCulloh and Dibeler, 1976
McCulloh, K.E.; Dibeler, V.H., Enthalpy of formation of methyl and methylene radicals of photoionization studies of methane and ketene, J. Chem. Phys., 1976, 64, 4445. [all data]

Notes

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

• Symbols used in this document:
  

  AE	Appearance energy
  IE (evaluated)	Recommended ionization energy
  ΔfH(+) ion,0K	Enthalpy of formation of positive ion at 0K
  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
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