Formic acid

• Formula: CH₂O₂
• Molecular weight: 46.0254
• IUPAC Standard InChI: InChI=1S/CH2O2/c2-1-3/h1H,(H,2,3) Copy

  
• IUPAC Standard InChIKey: BDAGIHXWWSANSR-UHFFFAOYSA-N Copy
• CAS Registry Number: 64-18-6
• 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: Methanoic acid; Aminic acid; Bilorin; Collo-Bueglatt; Collo-Didax; Formisoton; Formylic acid; Hydrogen carboxylic acid; Myrmicyl; HCOOH; Acide formique; Acido formico; Ameisensaeure; Kwas metaniowy; Kyselina mravenci; Mierenzuur; Rcra waste number U123; UN 1779; Formira; Add-F; Amasil
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• Information on this page:
  • Phase change data
  • Gas phase ion energetics data
  • Mass spectrum (electron ionization)
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Reaction thermochemistry data
  • Henry's Law data
  • Ion clustering data
  • IR Spectrum
  • Vibrational and/or electronic energy levels
  • Gas Chromatography
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
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Phase change 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:
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
AC - William E. Acree, Jr., James S. Chickos
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DH - Eugene S. Domalski and Elizabeth D. Hearing

Enthalpy of vaporization

Enthalpy of vaporization

Δ_vapH = A exp(-αT_r) (1 − T_r)^β
    Δ_vapH = Enthalpy of vaporization (at saturation pressure) (kJ/mol)
    T_r = reduced temperature (T / T_c)

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Antoine Equation Parameters

log₁₀(P) = A − (B / (T + C))
    P = vapor pressure (bar)
    T = temperature (K)

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Enthalpy of sublimation

Enthalpy of fusion

Entropy of fusion

Gas phase ion energetics data

Go To: Top, Phase change 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
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
LL - Sharon G. Lias and Joel F. Liebman

Ionization energy determinations

Appearance energy determinations

De-protonation reactions

 +  =

By formula: CHO₂^- + H⁺ = CH₂O₂

Mass spectrum (electron ionization)

Go To: Top, Phase change 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, Phase change 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.

Wilhoit, Chao, et al., 1985
Wilhoit, R.C.; Chao, J.; Hall, K.R., Thermodynamic Properties of Key Organic Compounds in the Carbon Range C1 to C4. Part 1. Properties of Condensed Phases, J. Phys. Chem. Ref. Data, 1985, 14, 1. [all data]

Stout and Fisher, 1941
Stout, J.W.; Fisher, L.H., The entropy of formic acid. The heat capacity from 15 to 300 K. Heats of fusion and vaporization, J. Chem. Phys., 1941, 9, 163-8. [all data]

Taylor and Bruton, 1952
Taylor, M.D.; Bruton, J., The vapour phase dissociation of some carboxylic acids. II. Formic and propionic acids., J. Am. Chem. Soc., 1952, 74, 4151. [all data]

Anselme and Teja, 1990
Anselme, M.J.; Teja, A.S., The critical properties of rapidly reacting substances, AIChE Symp. Ser., 1990, 86, 279, 128-32. [all data]

Ambrose and Ghiassee, 1987
Ambrose, D.; Ghiassee, N.B., Vapor Pressures and Critical Temperatures and Critical Pressures of Some Alkanoic Acids: C1 to C10, J. Chem. Thermodyn., 1987, 19, 505. [all data]

Majer and Svoboda, 1985
Majer, V.; Svoboda, V., Enthalpies of Vaporization of Organic Compounds: A Critical Review and Data Compilation, Blackwell Scientific Publications, Oxford, 1985, 300. [all data]

Stephenson and Malanowski, 1987
Stephenson, Richard M.; Malanowski, Stanislaw, Handbook of the Thermodynamics of Organic Compounds, 1987, https://doi.org/10.1007/978-94-009-3173-2 . [all data]

Konicek and Wadso, 1970
Konicek, J.; Wadso, I., Enthalpies of vaporization of organic compounds. VII. Some carboxylic acids, Acta Chem. Scand., 1970, 24, 2612-26. [all data]

Konicek, Wadsö, et al., 1970
Konicek, Jiri; Wadsö, Ingemar; Munch-Petersen, J.; Ohlson, Ragnar; Shimizu, Akira, Enthalpies of Vaporization of Organic Compounds. VII. Some Carboxylic Acids., Acta Chem. Scand., 1970, 24, 2612-2616, https://doi.org/10.3891/acta.chem.scand.24-2612 . [all data]

Stout and Fisher, 1941, 2
Stout, J.W.; Fisher, Leon H., The Entropy of Formic Acid. The Heat Capacity from 15 to 300°K. Heats of Fusion and Vaporization, J. Chem. Phys., 1941, 9, 2, 163, https://doi.org/10.1063/1.1750869 . [all data]

Ambrose and Ghiassee, 1987, 2
Ambrose, D.; Ghiassee, N.B., Vapour pressures and critical temperatures and critical pressures of some alkanoic acids: C1 to C10, The Journal of Chemical Thermodynamics, 1987, 19, 5, 505-519, https://doi.org/10.1016/0021-9614(87)90147-9 . [all data]

Dreisbach and Shrader, 1949
Dreisbach, R.R.; Shrader, S.A., Vapor Pressure--Temperature Data on Some Organic Compounds, Ind. Eng. Chem., 1949, 41, 12, 2879-2880, https://doi.org/10.1021/ie50480a054 . [all data]

Dreisbach and Martin, 1949
Dreisbach, R.R.; Martin, R.A., Physical Data on Some Organic Compounds, Ind. Eng. Chem., 1949, 41, 12, 2875-2878, https://doi.org/10.1021/ie50480a053 . [all data]

Campbell and Campbell, 1934
Campbell, Alan Newton; Campbell, Alexandra Jean Robson, The thermodynamics of binary liquid mixtures : formic acid and water, Trans. Faraday Soc., 1934, 30, 1109, https://doi.org/10.1039/tf9343001109 . [all data]

Coolidge, 1930
Coolidge, Albert Sprague, THE VAPOR PRESSURE AND HEATS OF FUSION AND VAPORIZATION OF FORMIC ACID, J. Am. Chem. Soc., 1930, 52, 5, 1874-1887, https://doi.org/10.1021/ja01368a018 . [all data]

Kahlbaum, 1894
Kahlbaum, G.W.A., Z. Phys. Chem., Stoechiom. Verwandtschaftsl., 1894, 13, 14. [all data]

Kahlbaum, 1883
Kahlbaum, Georg W.A., Ueber die Abhängigkeit der Siedetemperatur vom Luftdruck, Ber. Dtsch. Chem. Ges., 1883, 16, 2, 2476-2484, https://doi.org/10.1002/cber.188301602178 . [all data]

Kahlbaum, 1894, 2
Kahlbaum, G.W.A., Studien uber Dampfspannkraftsmessungen, Z. Phys. Chem. (Leipzig), 1894, 13, 14-55. [all data]

Calis-Van Ginkel, Calis, et al., 1978
Calis-Van Ginkel, C.H.D.; Calis, G.H.M.; Timmermans, C.W.M.; de Kruif, C.G.; Oonk, H.A.J., Enthalpies of sublimation and dimerization in the vapour phase of formic, acetic, propanoic, and butanoic acids, The Journal of Chemical Thermodynamics, 1978, 10, 11, 1083-1088, https://doi.org/10.1016/0021-9614(78)90082-4 . [all data]

Stull, 1947
Stull, Daniel R., Vapor Pressure of Pure Substances. Organic and Inorganic Compounds, Ind. Eng. Chem., 1947, 39, 4, 517-540, https://doi.org/10.1021/ie50448a022 . [all data]

Jones, 1960
Jones, A.H., Sublimation Pressure Data for Organic Compounds., J. Chem. Eng. Data, 1960, 5, 2, 196-200, https://doi.org/10.1021/je60006a019 . [all data]

Stout and Fisher, 1941, 3
Stout, J.W.; Fisher, L.H., The entropy of formic acid. The heat capacity from 15 to 300K. Heats of fusion and vaporization, J. Chem. Phys., 1941, 9, 163-168. [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]

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]

Bell, Ng, et al., 1975
Bell, S.; Ng, T.L.; Walsh, A.D., Vacuum ultraviolet spectra of formic and acetic acids, J. Chem. Soc. Faraday Trans. 2, 1975, 71, 393. [all data]

Warneck, 1974
Warneck, P., Heat of formation of the HCO radical, Z. Naturforsch. A:, 1974, 29, 350. [all data]

Knowles and Nicholson, 1974
Knowles, D.J.; Nicholson, A.J.C., Ionization energies of formic and acetic acid monomers, J. Chem. Phys., 1974, 60, 1180. [all data]

Watanabe, Yokoyama, et al., 1973
Watanabe, I.; Yokoyama, Y.; Ikeda, S., Vibrational structures in the photoelectron spectrum of formic acid, Chem. Phys. Lett., 1973, 19, 406. [all data]

Watanabe, Yokoyama, et al., 1973, 2
Watanabe, I.; Yokoyama, Y.; Ikeda, S., Lone pair ionization potentials of carboxylic acids determined by He(I) photoelectron spectroscopy, Bull. Chem. Soc. Jpn., 1973, 46, 1959. [all data]

Thomas, 1972
Thomas, R.K., Photoelectron spectroscopy of hydrogen-bonded systems: spectra of monomers, dimers and mixed complexes of carboxylic acides, Proc. R. Soc. London A:, 1972, 331, 249. [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]

Brundle, Turner, et al., 1969
Brundle, C.R.; Turner, D.W.; Robin, M.B.; Basch, H., Photoelectron spectroscopy of simple amides and carboxylic acids, Chem. Phys. Lett., 1969, 3, 292. [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 and Evans, 1937
Price, W.C.; Evans, W.M., The absorption spectrum of formic acid in the vacuum ultra-violet, Proc. Roy. Soc. (London), 1937, A162, 110. [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]

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]

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]

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]

Stepanov, Perov, et al., 1988
Stepanov, A.N.; Perov, A.A.; Kabanov, S.P.; Simonov, A.P., Formation of long-lived, highly excited atoms during dissociative excitation of CH₃CN, CH₃CH₂OH, CH₃COOH, HCOOH, and C₄H₄S molecules on electron impact, Russ. J. Phys. Chem., 1988, 22, 81. [all data]

Golovin, Akopyan, et al., 1979
Golovin, A.V.; Akopyan, M.E.; Vilesov, F.I.; Sergeev, Y.L., Ion-electron coincidence study of the photoionization of formic and acetic acids, Khim. Vys. Energ., 1979, 13, 200. [all data]

Akopyan and Villem, 1976
Akopyan, M.E.; Villem, Ya.Ya., Ion-molecule reactions in the photoionization of formic and acetic acid vapors, High Energy Chem., 1976, 10, 24. [all data]

Kim, Bradforth, et al., 1995
Kim, E.H.; Bradforth, S.E.; Arnold, D.W.; Metz, R.B.; Neumark, D.M., Study of HCO2 and DCO2 by Negative Ion Photoelectron Spectroscopy, J. Chem. Phys., 1995, 103, 18, 7801, https://doi.org/10.1063/1.470196 . [all data]

Caldwell, Renneboog, et al., 1989
Caldwell, G.; Renneboog, R.; Kebarle, P., Gas Phase Acidities of Aliphatic Carboxylic Acids, Based on Measurements of Proton Transfer Equilibria, Can. J. Chem., 1989, 67, 4, 661, https://doi.org/10.1139/v89-092 . [all data]

Fujio, McIver, et al., 1981
Fujio, M.; McIver, R.T., Jr.; Taft, R.W., Effects on the acidities of phenols from specific substituent-solvent interactions. Inherent substituent parameters from gas phase acidities, J. Am. Chem. Soc., 1981, 103, 4017. [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]

Muftakhov, Vasil'ev, et al., 1999
Muftakhov, M.V.; Vasil'ev, Y.V.; Mazunov, V.A., Determination of electron affinity of carbonyl radicals by means of negative ion mass spectrometry, Rapid Commun. Mass Spectrom., 1999, 13, 12, 1104-1108, https://doi.org/10.1002/(SICI)1097-0231(19990630)13:12<1104::AID-RCM619>3.0.CO;2-C . [all data]

Notes

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

• Symbols used in this document:
  

  AE	Appearance energy
  IE (evaluated)	Recommended ionization energy
  Ptriple	Triple point pressure
  Tboil	Boiling point
  Tc	Critical temperature
  Tfus	Fusion (melting) point
  Ttriple	Triple point temperature
  ΔfusH	Enthalpy of fusion
  ΔfusS	Entropy of fusion
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions
  ΔsubH	Enthalpy of sublimation
  ΔvapH	Enthalpy of vaporization
  ΔvapH°	Enthalpy of vaporization at standard conditions

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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