Formaldehyde

• Formula: CH₂O
• Molecular weight: 30.0260
• IUPAC Standard InChI: InChI=1S/CH2O/c1-2/h1H2 Copy

  
• IUPAC Standard InChIKey: WSFSSNUMVMOOMR-UHFFFAOYSA-N Copy
• CAS Registry Number: 50-00-0
• 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.
• Isotopologues:
  • methanal-d
• Other names: Methanal; BFV; Fannoform; Formaldehyde, gas; Formalin; Formalith; Formic aldehyde; Formol; Fyde; Lysoform; Methyl aldehyde; Methylene oxide; Morbicid; Oxomethane; Oxymethylene; Paraform; Superlysoform; Karsan; Methaldehyde; Aldehyde formique; Aldeide formica; Formaldehyd; Formalin-loesungen; Formalina; Formaline; NCI-C02799; Oplossingen; Aldehyd mravenci; Formalin 40; Rcra waste number U122; UN 1198; UN 2209; H2CO; Durine; Hercules 37M6-8; CH2O; NSC 298885; Fordor
• 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
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Phase change data
  • Ion clustering data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • Vibrational and/or electronic energy levels
  • Gas Chromatography
• Data at other public NIST sites:
  • Electron-Impact Ionization Cross Sections (on physics web site)
  • Gas Phase Kinetics Database
  • X-ray Photoelectron Spectroscopy Database, version 5.0
• Options:
  • Switch to SI units

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

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Reaction thermochemistry data

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

 +  = ( • )

By formula: CH₃O⁺ + CH₂O = (CH₃O⁺ • CH₂O)

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

 +  = ( • )

By formula: Li⁺ + CH₂O = (Li⁺ • CH₂O)

(CH₃O^- • 4294967295) +  = CH₃O^-

By formula: (CH₃O^- • 4294967295CH₂O) + CH₂O = CH₃O^-

CHO^- +  =

By formula: CHO^- + H⁺ = CH₂O

CH₂N⁺ +  = (CH₂N⁺ • )

By formula: CH₂N⁺ + CH₂O = (CH₂N⁺ • CH₂O)

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

=  + 

By formula: C₃H₉NO = C₂H₇N + CH₂O

 +  =  + 2

By formula: C₃H₈O₂ + H₂O = CH₂O + 2CH₄O

 +  =

By formula: CH₂O + C₃H₈N₂O = C₄H₁₀N₂O₂

2 +  =  + 

By formula: 2C₂H₇N + CH₂O = C₅H₁₄N₂ + H₂O

( • 2) +  = ( • 3)

By formula: (Fe⁺ • 2CH₂O) + CH₂O = (Fe⁺ • 3CH₂O)

( • 3) +  = ( • 4)

By formula: (Fe⁺ • 3CH₂O) + CH₂O = (Fe⁺ • 4CH₂O)

( • ) +  = ( • 2)

By formula: (Fe⁺ • CH₂O) + CH₂O = (Fe⁺ • 2CH₂O)

 +  =

By formula: C₂H₇N + CH₂O = C₃H₉NO

 +  =

By formula: H₂ + CO = CH₂O

 +  = ( • )

By formula: Fe⁺ + CH₂O = (Fe⁺ • CH₂O)

 +  = ( • )

By formula: Al⁺ + CH₂O = (Al⁺ • CH₂O)

= 3

By formula: C₃H₆O₃ = 3CH₂O

3 =

By formula: 3CH₂O = C₃H₆O₃

Gas phase ion energetics data

Go To: Top, 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 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
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 CH₂O⁺ (ion structure unspecified)

Proton affinity at 298K

Gas basicity at 298K

Ionization energy determinations

Appearance energy determinations

De-protonation reactions

CHO^- +  =

By formula: CHO^- + H⁺ = CH₂O

References

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

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

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]

Cunningham, Payzant, et al., 1972
Cunningham, A.J.; Payzant, J.D.; Kebarle, P., A Kinetic Study of the Proton Hydrate H+(H2O)n Equilibria in the Gas Phase, J. Am. Chem. Soc., 1972, 94, 22, 7627, https://doi.org/10.1021/ja00777a003 . [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]

Fehsenfeld, Dotan, et al., 1978
Fehsenfeld, F.C.; Dotan, I.; Albritton, D.L.; Howard, C.J.; Ferguson, E.E., Stratospheric Positive Ion Chemistry of Formaldehyde and Methanol, J. Geophys. Res., 1978, 83, C3, 1333, https://doi.org/10.1029/JC083iC03p01333 . [all data]

Meot-Ner (Mautner), 1992
Meot-Ner (Mautner), M., Intermolecular Forces in Organic Clusters, J. Am. Chem. Soc., 1992, 114, 9, 3312, https://doi.org/10.1021/ja00035a024 . [all data]

Larson, Clair, et al., 1982
Larson, J.W.; Clair, R.L.; McMahon, T.B., Bimolecular Production of Proton Bound Dimers in the Gas Phase. A Low Pressure Ion Cyclotron Resonance Technique for Examination of Solvent Exchange Equilibria and Determination of Single Molecule Solvation Energetics, Can. J. Chem., 1982, 60, 4, 542, https://doi.org/10.1139/v82-079 . [all data]

Woodin and Beauchamp, 1978
Woodin, R.L.; Beauchamp, J.L., Bonding of Li+ to Lewis Bases in the Gas Phase. Reversals in Methyl Substituent Effects for Different Reference Acids, J. Am. Chem. Soc., 1978, 100, 2, 501, https://doi.org/10.1021/ja00470a024 . [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]

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]

Nee, Osterwalder, et al., 2006
Nee, M.J.; Osterwalder, A.; Zhou, J.; Neumark, D.M., Slow electron velocity-map imaging photoelectron spectra of the methoxide anion, J. Chem. Phys., 2006, 125, 1, 014306, https://doi.org/10.1063/1.2212411 . [all data]

Osborn, Leahy, et al., 1998
Osborn, D.L.; Leahy, D.J.; Kim, E.H.; deBeer, E.; Neumark, D.M., Photoelectron spectroscopy of CH3O- and CD3O-, Chem. Phys. Lett., 1998, 292, 4-6, 651-655, https://doi.org/10.1016/S0009-2614(98)00717-9 . [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]

Murray, Miller, et al., 1986
Murray, K.K.; Miller, T.M.; Leopold, D.G.; Lineberger, W.C., Laser photoelectron spectroscopy of the Formylf anion, J. Chem. Phys., 1986, 84, 2520. [all data]

Karpas and Klein, 1975
Karpas, Z.; Klein, F.S., Negative ion-molecule reactions in a mixture of ammonia-formaldehyde - an ICR mass spectrometry study, Int. J. Mass Spectrom. Ion Phys., 1975, 18, 65. [all data]

Tanaka, Mackay, et al., 1978
Tanaka, K.; Mackay, G.I.; Bohme, D.K., Rate and Equilibrium Constant Measurements for Gas-Phase Proton-Transfer Reactions Involving H2O, H2S, HCN, and H2CO, Can. J. Chem., 1978, 56, 2, 193, https://doi.org/10.1139/v78-031 . [all data]

Meot-Ner (Mautner), 1978
Meot-Ner (Mautner), M., Solvation of the Proton by HCN and CH3CN. Condensation of HCN with Ions in the Gas Phase., J. Am. Chem. Soc., 1978, 100, 15, 4694, https://doi.org/10.1021/ja00483a012 . [all data]

Rogers and Rapiejko, 1974
Rogers, F.E.; Rapiejko, R.J., Thermochemistry of carbonyl addition reactions. II. Enthalpy of addition of dimethylamine to formaldehyde, J. Phys. Chem., 1974, 78, 599-603. [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]

Perepelkova, Igranova, et al., 1981
Perepelkova, T.I.; Igranova, E.G.; Moiseev, V.D.; Demchenko, L.Ya.; Zhuravleva, I.I., Calorimetric study of the methylolation of 1,1-dimethylurea, Khim. Promst. Ser. Proizvod. Pererab. Plastmass Sint. Smol, 1981, 15-18. [all data]

Rodgers and Armentrout, 2000
Rodgers, M.T.; Armentrout, P.B., Noncovalent Metal-Ligand Bond Energies as Studied by Threshold Collision-Induced Dissociation, Mass Spectrom. Rev., 2000, 19, 4, 215, https://doi.org/10.1002/1098-2787(200007)19:4<215::AID-MAS2>3.0.CO;2-X . [all data]

Newton and Dodge, 1933
Newton, R.H.; Dodge, B.F., The equilibrium between carbon monoxide, hydrogen, formaldehyde and methanol. I. The reactions CO + H₂ = HCOH and H₂ + HCOH = CH₃OH, J. Am. Chem. Soc., 1933, 55, 4747-4759. [all data]

Bouchard, Brenner, et al., 1997
Bouchard, F.; Brenner, V.; Carra, C.; Hepburn, J.W.; Koyanagi, G.K.; McMahon, T.B.; Ohanessian, G.; Peschke, M., Energetics and Structure of Complexes of Al+ with Small Organic Molecules in the Gas Phase, J. Phys. Chem. A, 1997, 101, 33, 5885, https://doi.org/10.1021/jp9703465 . [all data]

Busfield and Merigold, 1969
Busfield, W.K.; Merigold, D., The gas-phase equilibrium between trioxan and formaldehyde: The standard enthalpy and entropy of the trimerisation of formaldehyde, J. Chem. Soc. A, 1969, 19, 2975-2977. [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 Leblanc, 2000
Bouchoux, G.; Leblanc, D., Gas-phase basicity of formaldehyde by the thermokinetic method, European J. Mass Spectrom., 2000, 6, 443. [all data]

Ohno, Okamura, et al., 1995
Ohno, K.; Okamura, K.; Yamakado, H.; Hoshino, S.; Takami, T.; Yamauchi, M., Penning ionization of HCHO, CH₂CH₂, and CH₂CHCHO by collision with He*(2 3S) metastable atoms, J. Phys. Chem., 1995, 99, 14247. [all data]

Niu, Shirley, et al., 1993
Niu, B.; Shirley, D.A.; Bai, Y., High resolution photoelectron spectroscopy and femtosecond intramolecular dynamics of H₂CO⁺ and D₂CO⁺, J. Chem. Phys., 1993, 98, 4377. [all data]

Traeger, 1985
Traeger, J.C., Heat of formation for the formyl cation by photoionization mass spectrometry, Int. J. Mass Spectrom. Ion Processes, 1985, 66, 271. [all data]

Kimura, Katsumata, et al., 1981
Kimura, K.; Katsumata, S.; Achiba, Y.; Yamazaki, T.; Iwata, S., Ionization energies, Ab initio assignments, and valence electronic structure for 200 molecules in Handbook of HeI Photoelectron Spectra of Fundamental Organic Compounds, Japan Scientific Soc. Press, Tokyo, 1981. [all data]

Von Niessen, Bieri, et al., 1980
Von Niessen, W.; Bieri, G.; Asbrink, L., 30.4 nm He(II) photoelectron spectra of organic molecules. Part III. Oxo-compounds (C,H,O), J. Electron Spectrosc. Relat. Phenom., 1980, 21, 175. [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]

Drury-Lessard and Moule, 1977
Drury-Lessard, C.R.; Moule, D.C., The higher Rydberg states of formaldehyde, Chem. Phys. Lett., 1977, 47, 300. [all data]

Guyon, Chupka, et al., 1976
Guyon, P.M.; Chupka, W.A.; Berkowitz, J., Photoionization mass spectrometric study of formaldehyde H₂CO, HDCO, and D₂CO, J. Chem. Phys., 1976, 65, 1419. [all data]

Warneck, 1971
Warneck, P., Photoionisation von methanol und formaldehyd, Z. Naturforsch. A:, 1971, 26, 2047. [all data]

Mentall, Gentieu, et al., 1971
Mentall, J.E.; Gentieu, E.P.; Krauss, M.; Neumann, D., Photoionization and absorption spectrum of formaldehyde in the vacuum ultraviolet, J. Chem. Phys., 1971, 55, 5471. [all data]

Matthews and Warneck, 1969
Matthews, C.S.; Warneck, P., Heats of formation of CHO⁺ and C₃H₃⁺ by photoionization, J. Chem. Phys. 5, 1969, 1, 854. [all data]

Baker, Baker, et al., 1968
Baker, A.D.; Baker, C.; Brundle, C.R.; Turner, D.W., The electronic structures of methane, ethane, ethylene and formaldehyde studied by high-resolution molecular photoelectron spectroscopy, Intern. J. Mass Spectrom. Ion Phys., 1968, 1, 285. [all data]

Kanomata, 1961
Kanomata, I., Mass-spectrometric study on ionization and dissociation of formaldehyde, acetaldehyde, acetone and ethyl methyl ketone by electron impact, Bull. Chem. Soc. Japan, 1961, 34, 1864. [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]

Watanabe, 1957
Watanabe, K., Ionization potentials of some molecules, J. Chem. Phys., 1957, 26, 542. [all data]

Price, 1935
Price, W.C., The far ultraviolet absorption spectra of formaldehyde and the alkyl derivatives of H, O and H₂S, J. Chem. Phys., 1935, 3, 256. [all data]

Rao, 1975
Rao, C.N.R., Lone-pair ionization bands of chromophores in the photoelectron spectra of organic molecules, Indian J. Chem., 1975, 13, 950. [all data]

Wankenne, Caprace, et al., 1984
Wankenne, H.; Caprace, G.; Momigny, J., Unimolecular decay of metastable ions in formaldehyde, Int. J. Mass Spectrom. Ion Processes, 1984, 57, 149. [all data]

Brand and Reed, 1957
Brand, J.C.D.; Reed, R.I., The electronic spectrum of formaldehyde. Part II. Mechanisms of dissociation of formaldehyde and the formaldehyde molecular ion, J. Chem. Soc., 1957, 2386. [all data]

Notes

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