Acetaldehyde

• Formula: C₂H₄O
• Molecular weight: 44.0526
• IUPAC Standard InChI: InChI=1S/C2H4O/c1-2-3/h2H,1H3 Copy

  
• IUPAC Standard InChIKey: IKHGUXGNUITLKF-UHFFFAOYSA-N Copy
• CAS Registry Number: 75-07-0
• 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: Acetic aldehyde; Ethanal; Ethyl aldehyde; CH3CHO; Acetaldehyd; Aldehyde acetique; Aldeide acetica; NCI-C56326; Octowy aldehyd; Acetylaldehyde; Rcra waste number U001; UN 1089; NSC 7594
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Reaction thermochemistry data
  • References
  • Notes
• Other data available:
  • Phase change data
  • 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
• 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, Condensed phase thermochemistry data, Reaction thermochemistry 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 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

Condensed phase thermochemistry data

Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry 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 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

Reaction thermochemistry data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry 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 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
RCD - Robert C. Dunbar

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

C₂H₃O^- +  =

By formula: C₂H₃O^- + H⁺ = C₂H₄O

C₂H₅O⁺ +  = (C₂H₅O⁺ • )

By formula: C₂H₅O⁺ + C₂H₄O = (C₂H₅O⁺ • C₂H₄O)

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

C₂H₇O⁺ +  = (C₂H₇O⁺ • )

By formula: C₂H₇O⁺ + C₂H₄O = (C₂H₇O⁺ • C₂H₄O)

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

C₂H₅O⁺ +  = (C₂H₅O⁺ • )

By formula: C₂H₅O⁺ + C₂H₄O = (C₂H₅O⁺ • C₂H₄O)

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

C₂H₃O^- +  =

By formula: C₂H₃O^- + H⁺ = C₂H₄O

 +  = ( • )

By formula: Cl^- + C₂H₄O = (Cl^- • C₂H₄O)

 +  = ( • )

By formula: C₂H₃O₂^- + C₂H₄O = (C₂H₃O₂^- • C₂H₄O)

Bond type: Hydrogen bonds of deprotonated acids to ketones/

 +  =

By formula: H₂ + C₂H₄O = C₂H₆O

(C₂H₅O^- • 4294967295) +  = C₂H₅O^-

By formula: (C₂H₅O^- • 4294967295C₂H₄O) + C₂H₄O = C₂H₅O^-

 +  = ( • )

By formula: NO^- + C₂H₄O = (NO^- • C₂H₄O)

 +  = ( • )

By formula: Li⁺ + C₂H₄O = (Li⁺ • C₂H₄O)

3 =

By formula: 3C₂H₄O = C₆H₁₂O₃

 +  = ( • )

By formula: Mg⁺ + C₂H₄O = (Mg⁺ • C₂H₄O)

 +  = 2 + 

By formula: C₄H₁₀O₂ + H₂O = 2CH₄O + C₂H₄O

 +  = 2 + 

By formula: C₄H₁₀O₂ + H₂O = 2CH₄O + C₂H₄O

 +  = 2 + 

By formula: C₄H₁₀O₂ + H₂O = 2CH₄O + C₂H₄O

2 +  =  + 

By formula: 2CH₄O + C₂H₄O = C₄H₁₀O₂ + H₂O

 +  =  + 

By formula: C₂H₄O + I₂ = HI + C₂H₃IO

 +  =  + 

By formula: H₂O + C₈H₁₀N₂ = C₆H₈N₂ + C₂H₄O

= 3

By formula: C₆H₁₂O₃ = 3C₂H₄O

 +  = ( • )

By formula: Na⁺ + C₂H₄O = (Na⁺ • C₂H₄O)

 +  = ( • )

By formula: Ag⁺ + C₂H₄O = (Ag⁺ • C₂H₄O)

References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Reaction thermochemistry data, Notes

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

Wiberg, Crocker, et al., 1991
Wiberg, K.B.; Crocker, L.S.; Morgan, K.M., Thermochemical studies of carbonyl compounds. 5. Enthalpies of reduction of carbonyl groups, J. Am. Chem. Soc., 1991, 113, 3447-3450. [all data]

Thermodynamics Research Center, 1997
Thermodynamics Research Center, Selected Values of Properties of Chemical Compounds., Thermodynamics Research Center, Texas A&M University, College Station, Texas, 1997. [all data]

Pitzer K.S., 1949
Pitzer K.S., Jr., Thermodynamics and vibrational spectrum of acetaldehyde, J. Am. Chem. Soc., 1949, 71, 2842-2844. [all data]

Della Vedova C.O., 1991
Della Vedova C.O., Raman and infrared spectra and photochemical behavior of acetaldehyde isolated in matrixes, J. Raman Spectrosc., 1991, 22, 505-507. [all data]

East A.L.L., 1997
East A.L.L., Ab initio statistical thermodynamical models for the computation of third-law entropies, J. Chem. Phys., 1997, 106, 6655-6674. [all data]

Chao J., 1980
Chao J., Perfect gas thermodynamic properties of methanal, ethanal and their deuterated species, Thermochim. Acta, 1980, 41, 41-54. [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]

Coleman C.F., 1949
Coleman C.F., The heat capacity of organic vapors. V. Acetaldehyde, J. Am. Chem. Soc., 1949, 71, 2839-2841. [all data]

Lebedev and Vasil'ev, 1988
Lebedev, B.V.; Vasil'ev, V.G., Thermodynamics of ethanal at 0-300 K, Zhur. Fiz. Khim., 1988, 62, 3099-3102. [all data]

Connor, Elving, et al., 1947
Connor, A.Z.; Elving, P.J.; Steingiser, S., Specific heat of acetaldehyde and acetaldehyde dibutyl acetal, J. Am. Chem. Soc., 1947, 69, 1532. [all data]

Mead, Lykke, et al., 1984
Mead, R.D.; Lykke, K.R.; Lineberger, W.C.; Marks, J.; Brauman, J.I., Spectroscopy and Dynamics of the Dipole-Bound State of Acetaldehyde Enolate., J. Chem. Phys., 1984, 81, 11, 4883., https://doi.org/10.1063/1.447515 . [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]

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]

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]

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]

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]

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]

Meot-ner, 1988
Meot-ner, M., Ionic Hydrogen Bond and Ion Solvation. ₆. Interaction Energies of the Acetate Ion with Organic Molecules. Comparison of CH₃COO^- with Cl^-, CN^-, and SH^-, J. Am. Chem. Soc., 1988, 110, 12, 3854, https://doi.org/10.1021/ja00220a022 . [all data]

Dolliver, Gresham, et al., 1938
Dolliver, M.A.; Gresham, T.L.; Kistiakowsky, G.B.; Smith, E.A.; Vaughan, W.E., Heats of organic reactions. VI. Heats of hydrogenation of some oxygen-containing compounds, J. Am. Chem. Soc., 1938, 60, 440-450. [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]

Ramond, Davico, et al., 2000
Ramond, T.M.; Davico, G.E.; Schwartz, R.L.; Lineberger, W.C., Vibronic structure of alkoxy radicals via photoelectron spectroscopy, J. Chem. Phys., 2000, 112, 3, 1158-1169, https://doi.org/10.1063/1.480767 . [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]

Staley and Beauchamp, 1975
Staley, R.H.; Beauchamp, J.L., Intrinsic Acid - Base Properties of Molecules. Binding Energies of Li+ to pi - and n - Donor Bases, J. Am. Chem. Soc., 1975, 97, 20, 5920, https://doi.org/10.1021/ja00853a050 . [all data]

Berman and Beauchamp, 1986
Berman, D.W.; Beauchamp, J.L., Quoted in Keesee and Castleman, 1986, 1986. [all data]

Dzidic and Kebarle, 1970
Dzidic, I.; Kebarle, P., Hydration of the Alkali Ions in the Gas Phase. Enthalpies and Entropies of Reactions M+(H2O)n-1 + H2O = M+(H2O)n, J. Phys. Chem., 1970, 74, 7, 1466, https://doi.org/10.1021/j100702a013 . [all data]

Krasnov, Ozherel'eva, et al., 1983
Krasnov, V.L.; Ozherel'eva, N.K.; Trub, E.P.; Tsvetkov, V.G.; Bodrikov, I.V., Trimerization of aldehydes under the action of sulfur dioxide, J. Gen. Chem. USSR, 1983, 53, 2135-2138. [all data]

Busfield, Lee, et al., 1973
Busfield, W.K.; Lee, R.M.; Merifold, D., Gas phase equilibrium between acetaldehyde and paraldehyde, thermodynamic values for the trimerisation of acetaldehyde and the polymerisability of paraldehyde, J. Chem. Soc. Faraday Trans. 1, 1973, 69, 936-940. [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]

Wiberg, 1980
Wiberg, K.B., Energies of organic compounds, Rept. DOE-E(11-1)4060 Prepared for US Dept. of Energy by Yale Univ., New Haven, CT. Avail. NTIS, 1980, 1-24. [all data]

Birley and Skinner, 1970
Birley, G.I.; Skinner, H.A., Enthalpies of hydrolysis of dimethoxymethane and 1,1-dimethoxyethane, Trans. Faraday Soc., 1970, 66, 791-793. [all data]

Wiberg, Morgan, et al., 1994
Wiberg, K.B.; Morgan, K.M.; Maltz, H., Thermochemistry of carbonyl reactions. 6. A study of hydration equilibria, J. Am. Chem. Soc., 1994, 116, 11067-11077. [all data]

Walsh and Benson, 1966
Walsh, R.; Benson, S.W., The heats of formation of acetyl iodide and the acetyl radical, J. Phys. Chem., 1966, 70, 3751-3753. [all data]

Landrieu, 1905
Landrieu, M.Ph., Thermochimie. - Thermochimie des hydrazones, Compt. Rend., 1905, 141, 358-361. [all data]

Armentrout and Rodgers, 2000
Armentrout, P.B.; Rodgers, M.T., An Absolute Sodium Cation Affinity Scale: Threshold Collision-Induced Dissociation Experiments and ab Initio Theory, J. Phys. Chem A, 2000, 104, 11, 2238, https://doi.org/10.1021/jp991716n . [all data]

Ho, Yang, et al., 1997
Ho, Y.-P.; Yang, Y.-C.; Klippenstein, S.J.; Dunbar, R.C., Binding Energies of Ag+ and Cd+ Complexes from Analysis of Radiative Association Kinetics, J. Phys. Chem. A, 1997, 101, 18, 3338, https://doi.org/10.1021/jp9637284 . [all data]

Notes

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Reaction thermochemistry data, References

• Symbols used in this document:
  

  Cp,gas	Constant pressure heat capacity of gas
  Cp,liquid	Constant pressure heat capacity of liquid
  S°liquid	Entropy of liquid at standard conditions
  ΔfH°gas	Enthalpy of formation of gas at standard conditions
  ΔfH°liquid	Enthalpy of formation of liquid 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.