Ketene
- Formula: C2H2O
- Molecular weight: 42.0367
- IUPAC Standard InChIKey: CCGKOQOJPYTBIH-UHFFFAOYSA-N
- 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:
- Other data available:
- Data at other public NIST sites:
- Options:
Data at NIST subscription sites:
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.
Reaction thermochemistry data
Go To: Top, 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
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 181. ± 16. | kJ/mol | N/A | Marks, Brauman, et al., 1988 | gas phase; B |
ΔrH° | 187. ± 16. | kJ/mol | Ther | Farid and McMahon, 1980 | gas phase; Between MeCOCH2F, cyclopentadiene; value altered from reference due to change in acidity scale; B |
ΔrH° | 186. ± 16. | kJ/mol | N/A | Wenthold and Squires, 1995 | gas phase; Re-evaluation of literature thermo cycle; B |
ΔrH° | 148. ± 8.4 | kJ/mol | IMRE | Larson and McMahon, 1983 | gas phase; These relative affinities are ca. 10 kcal/mol weaker than threshold values (see Wenthold and Squires, 1995) for donors greater than ca. 27 kcal/mol in free energy. This discrepancy has not yet been resolved, though the stronger value appears preferable.; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 115. ± 8.4 | kJ/mol | IMRE | Larson and McMahon, 1983 | gas phase; These relative affinities are ca. 10 kcal/mol weaker than threshold values (see Wenthold and Squires, 1995) for donors greater than ca. 27 kcal/mol in free energy. This discrepancy has not yet been resolved, though the stronger value appears preferable.; B |
By formula: F- + C2H2O = (F- • C2H2O)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 148. | kJ/mol | ICR | Larson and McMahon, 1983 | gas phase; switching reaction(F-)H2O, Entropy change calculated or estimated; Arshadi, Yamdagni, et al., 1970; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 111. | J/mol*K | N/A | Larson and McMahon, 1983 | gas phase; switching reaction(F-)H2O, Entropy change calculated or estimated; Arshadi, Yamdagni, et al., 1970; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 115. | kJ/mol | ICR | Larson and McMahon, 1983 | gas phase; switching reaction(F-)H2O, Entropy change calculated or estimated; Arshadi, Yamdagni, et al., 1970; M |
C2HO- + =
By formula: C2HO- + H+ = C2H2O
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 1526. ± 8.8 | kJ/mol | G+TS | Oakes, Jones, et al., 1983 | gas phase; Acid: ketene; value altered from reference due to change in acidity scale; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 1497. ± 8.4 | kJ/mol | IMRB | Oakes, Jones, et al., 1983 | gas phase; Acid: ketene; value altered from reference due to change in acidity scale; B |
(C2H3O- • 4294967295) +
= C2H3O-
By formula: (C2H3O- • 4294967295C2H2O) + C2H2O = C2H3O-
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 257. ± 9.6 | kJ/mol | N/A | Bartmess, Scott, et al., 1979 | gas phase; Acid: ethanal. The enol is 9.6 kcal/mol more acidic: Holmes and Lossing, 1982; value altered from reference due to change in acidity scale; B |
(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
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 143. ± 4.6 | kJ/mol | N/A | Nimlos, Soderquist, et al., 1989 | gas phase; B |
ΔrH° | 6.7 ± 9.2 | kJ/mol | Ther | DePuy, Bierbaum, et al., 1985 | gas phase; B |
By formula: HNaO + C2H2O = C2H3NaO2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -208.2 ± 1.6 | kJ/mol | Cm | Nuttall, Laufer, et al., 1971 | gas phase; ALS |
ΔrH° | -197.3 | kJ/mol | Cm | Rice and Greenberg, 1934 | gas phase; ALS |
(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
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 203. ± 9.6 | kJ/mol | N/A | Bartmess, Scott, et al., 1979 | gas phase; value altered from reference due to change in acidity scale; B |
(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
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 122. ± 12. | kJ/mol | N/A | Taft, 1987 | gas phase; value altered from reference due to change in acidity scale; B |
By formula: C4H6O2S = C2H2O + C2H4OS
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 94.7 | kJ/mol | Eqk | Blake and Speis, 1974 | gas phase; Heat of formation derived by 77PED/RYL; ALS |
(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
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 231. ± 13. | kJ/mol | N/A | Grabowski and Cheng, 1989 | gas phase; B |
By formula: C2H2O + C2H4O2 = C4H6O3
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -87.5 ± 2.2 | kJ/mol | Eqk | Blake, Davies, et al., 1971 | gas phase; ALS |
By formula: C2H2O + C4H10O = C6H12O2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -146.9 | kJ/mol | Cm | Rice and Greenberg, 1934 | liquid phase; ALS |
By formula: C2H2O + C4H10O = C6H12O2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -143.8 | kJ/mol | Cm | Rice and Greenberg, 1934 | liquid phase; ALS |
By formula: C2H2O + C4H10O = C6H12O2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -144.5 | kJ/mol | Cm | Rice and Greenberg, 1934 | liquid phase; ALS |
By formula: C2H2O + C4H10O = C6H12O2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -98.28 | kJ/mol | Cm | Rice and Greenberg, 1934 | liquid phase; ALS |
By formula: C2H2O + C3H8O = C5H10O2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -150.2 | kJ/mol | Cm | Rice and Greenberg, 1934 | liquid phase; ALS |
By formula: C2H2O + C2H4OS = C4H6O2S
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -94.7 | kJ/mol | Eqk | Blake and Speis, 1974 | gas phase; ALS |
By formula: C2H2O + C2H6O = C4H8O2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -152.5 | kJ/mol | Cm | Rice and Greenberg, 1934 | gas phase; ALS |
By formula: C2H2O + C3H8O = C5H10O2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -147.8 | kJ/mol | Cm | Rice and Greenberg, 1934 | gas phase; ALS |
By formula: C2H2O + CH4O = C3H6O2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -154.5 | kJ/mol | Cm | Rice and Greenberg, 1934 | gas phase; ALS |
References
Go To: Top, Reaction thermochemistry data, 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]
Notes
Go To: Top, Reaction thermochemistry data, References
- Symbols used in this document:
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.