Formic acid

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Phase change 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:
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

Quantity Value Units Method Reference Comment
Tboil373.9 ± 0.5KAVGN/AAverage of 25 out of 30 values; Individual data points
Quantity Value Units Method Reference Comment
Tfus281.5 ± 0.6KAVGN/AAverage of 9 values; Individual data points
Quantity Value Units Method Reference Comment
Ttriple281.45KN/AWilhoit, Chao, et al., 1985Uncertainty assigned by TRC = 0.1 K; TRC
Ttriple281.40KN/AStout and Fisher, 1941Uncertainty assigned by TRC = 0.06 K; TRC
Quantity Value Units Method Reference Comment
Ptriple0.0233atmN/ATaylor and Bruton, 1952Uncertainty assigned by TRC = 0.000066 atm; TRC
Quantity Value Units Method Reference Comment
Tc577.KN/AAnselme and Teja, 1990Uncertainty assigned by TRC = 30. K; Tc > 577 K, which was observed with decomposition; TRC
Tc588.KN/AAmbrose and Ghiassee, 1987Uncertainty assigned by TRC = 10. K; TRC
Tc580.KN/AMajer and Svoboda, 1985 
Quantity Value Units Method Reference Comment
Δvap11.1kcal/molN/AMajer and Svoboda, 1985 
Δvap8.60kcal/molAStephenson and Malanowski, 1987Based on data from 283. to 384. K.; AC
Δvap11.1 ± 0.1kcal/molCKonicek and Wadso, 1970ALS
Δvap11.1 ± 0.1kcal/molCKonicek, Wadsö, et al., 1970AC
Δvap4.76kcal/molN/AStout and Fisher, 1941, 2AC

Enthalpy of vaporization

ΔvapH (kcal/mol) Temperature (K) Method Reference Comment
5.423373.8N/AMajer and Svoboda, 1985 
8.41315.EBAmbrose and Ghiassee, 1987, 2Based on data from 300. to 392. K.; AC
8.41325.N/ADreisbach and Shrader, 1949Based on data from 310. to 374. K. See also Dreisbach and Martin, 1949.; AC
7.07303.N/ACampbell and Campbell, 1934AC
4.85315.N/ACoolidge, 1930Based on data from 273. to 373. K.; AC
5.00338.N/ACoolidge, 1930Based on data from 273. to 373. K.; AC
4.88315.CCoolidge, 1930AC
5.04338.CCoolidge, 1930AC
8.80288.N/AKahlbaum, 1894Based on data from 273. to 307. K.; AC
11.4374.N/AKahlbaum, 1883Based on data from 295. to 374. K.; AC

Enthalpy of vaporization

ΔvapH = A exp(-αTr) (1 − Tr)β
    ΔvapH = Enthalpy of vaporization (at saturation pressure) (kcal/mol)
    Tr = reduced temperature (T / Tc)

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Temperature (K) 298. to 374.
A (kcal/mol) 5.69
α 2.1043
β -1.2652
Tc (K) 580.
ReferenceMajer and Svoboda, 1985

Antoine Equation Parameters

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

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Temperature (K) A B C Reference Comment
273.7 to 307.41.99550515.-139.408Kahlbaum, 1894, 2Coefficents calculated by NIST from author's data.

Enthalpy of sublimation

ΔsubH (kcal/mol) Temperature (K) Method Reference Comment
14.5275.N/AStephenson and Malanowski, 1987Based on data from 268. to 281. K.; AC
14.8 ± 0.2213.TE,MECalis-Van Ginkel, Calis, et al., 1978Based on data from 203. to 218. K.; AC
14.4264.AStull, 1947Based on data from 253. to 275. K.; AC
14.5266.N/ACoolidge, 1930Based on data from 265. to 268. K. See also Jones, 1960.; AC

Enthalpy of fusion

ΔfusH (kcal/mol) Temperature (K) Reference Comment
3.0301281.40Stout and Fisher, 1941, 3DH

Entropy of fusion

ΔfusS (cal/mol*K) Temperature (K) Reference Comment
10.77281.40Stout and Fisher, 1941, 3DH

In addition to the Thermodynamics Research Center (TRC) data available from this site, much more physical and chemical property data is available from the following TRC products:


Gas phase ion energetics data

Go To: Top, Phase change 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
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

Quantity Value Units Method Reference Comment
IE (evaluated)11.33 ± 0.01eVN/AN/AL
Quantity Value Units Method Reference Comment
Proton affinity (review)177.3kcal/molN/AHunter and Lias, 1998HL
Quantity Value Units Method Reference Comment
Gas basicity169.8kcal/molN/AHunter and Lias, 1998HL

Ionization energy determinations

IE (eV) Method Reference Comment
11.31PITraeger, 1985LBLHLM
11.329 ± 0.002SBell, Ng, et al., 1975LLK
11.16 ± 0.03PIWarneck, 1974LLK
11.314 ± 0.002PIKnowles and Nicholson, 1974LLK
11.3PEWatanabe, Yokoyama, et al., 1973LLK
11.33PEWatanabe, Yokoyama, et al., 1973, 2LLK
11.35 ± 0.03PEThomas, 1972LLK
11.16 ± 0.03PIMatthews and Warneck, 1969RDSH
11.33PEBrundle, Turner, et al., 1969RDSH
11.05 ± 0.03PIVilesov, 1960RDSH
11.05 ± 0.01PIWatanabe, 1957RDSH
11.33SPrice and Evans, 1937RDSH
11.5PEVon Niessen, Bieri, et al., 1980Vertical value; LLK
11.34PEBenoit and Harrison, 1977Vertical value; LLK
10.7PERao, 1975Vertical value; LLK
11.51PEKimura, Katsumata, et al., 1975Vertical value; LLK

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
C+22.7 ± 0.5O+H2OEIStepanov, Perov, et al., 1988LL
CHO+12.76OHPITraeger, 1985LBLHLM
CHO+13.0 ± 0.1OHPIGolovin, Akopyan, et al., 1979LLK
CHO+12.79 ± 0.03OHPIWarneck, 1974LLK
CHO+12.79 ± 0.03OHPIMatthews and Warneck, 1969RDSH
CHO2+12.4 ± 0.1HPIGolovin, Akopyan, et al., 1979LLK
CHO2+12.26HPIAkopyan and Villem, 1976LLK
CHO2+12.29 ± 0.03HPIWarneck, 1974LLK
HO+17.97 ± 0.06HCOPIWarneck, 1974LLK
O+20.0 ± 0.5CO+H2EIStepanov, Perov, et al., 1988LL

De-protonation reactions

HCO2 anion + Hydrogen cation = Formic acid

By formula: CHO2- + H+ = CH2O2

Quantity Value Units Method Reference Comment
Δr346.2 ± 1.2kcal/molD-EAKim, Bradforth, et al., 1995gas phase; dHacid(0K) = 344.67±0.62 kcal/mol; B
Δr345.3 ± 2.2kcal/molG+TSCaldwell, Renneboog, et al., 1989gas phase; B
Δr345.4 ± 2.2kcal/molG+TSFujio, McIver, et al., 1981gas phase; value altered from reference due to change in acidity scale; B
Δr345.2 ± 2.9kcal/molG+TSCumming and Kebarle, 1978gas phase; B
Δr340.1 ± 4.6kcal/molEIAEMuftakhov, Vasil'ev, et al., 1999gas phase; B
Quantity Value Units Method Reference Comment
Δr339.2 ± 1.5kcal/molH-TSKim, Bradforth, et al., 1995gas phase; dHacid(0K) = 344.67±0.62 kcal/mol; B
Δr338.3 ± 2.0kcal/molIMRECaldwell, Renneboog, et al., 1989gas phase; B
Δr338.4 ± 2.0kcal/molIMREFujio, McIver, et al., 1981gas phase; value altered from reference due to change in acidity scale; B
Δr338.2 ± 2.0kcal/molIMRECumming and Kebarle, 1978gas phase; B

References

Go To: Top, Phase change 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.

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, References