Octanoic acid

• Formula: C₈H₁₆O₂
• Molecular weight: 144.2114
• IUPAC Standard InChI: InChI=1S/C8H16O2/c1-2-3-4-5-6-7-8(9)10/h2-7H2,1H3,(H,9,10) Copy

  
• IUPAC Standard InChIKey: WWZKQHOCKIZLMA-UHFFFAOYSA-N Copy
• CAS Registry Number: 124-07-2
• 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: n-Caprylic acid; n-Octanoic acid; n-Octoic acid; n-Octylic acid; Neo-Fat 8; Caprylic acid; Enantic acid; Octylic acid; 1-Heptanecarboxylic acid; Heptane-1-carboxylic acid; Octic acid; Hexacid 898; C-8 Acid; Kyselina kaprylova; Lunac 8-95; Emery 657; Octoic acid; Prifac 2901; 1-Octanoic acid; NSC 5024; Prifrac 2901
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• Information on this page:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Phase change data
  • References
  • Notes
• Other data available:
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • Gas Chromatography
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Gas phase thermochemistry data

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

Data compiled by: Donald R. Burgess, Jr.

Condensed phase thermochemistry data

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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:
DRB - Donald R. Burgess, Jr.
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

Phase change data

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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:
BS - Robert L. Brown and Stephen E. Stein
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

Antoine Equation Parameters

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

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Enthalpy of fusion

Entropy of fusion

Enthalpy of phase transition

Entropy of phase transition

References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Notes

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

Adriaanse, Dekker, et al., 1965
Adriaanse, N.; Dekker, H.; Coops, J., Heats of combustion of normal saturated fatty acids and their methyl esters, Rec. Trav. Chim. Pays/Bas, 1965, 84, 393-407. [all data]

Baccanari, Novinski, et al., 1968
Baccanari, D.P.; Novinski, J.A.; Pan, Y.; Yevitz, M.M.; Swain, H.A., Jr., Heats of sublimation and vaporization at 25° of long chain fatty acids and methyl esters, Trans. Faraday Soc., 1968, 64, 1201. [all data]

Lebedeva, 1964
Lebedeva, N.D., Heats of combustion of monocarboxylic acids, Russ. J. Phys. Chem. (Engl. Transl.), 1964, 38, 1435-1437. [all data]

Schaake, van Miltenburg, et al., 1982
Schaake, R.C.F.; van Miltenburg, J.C.; De Kruif, C.G., Thermodynamic properties of the normal alkanoic acids. II. Molar heat capacities of seven even-numbered normal alkanoic acids, J. Chem. Thermodynam., 1982, 14, 771-778. [all data]

Garner and Randall, 1924
Garner, W.E.; Randall, F.C., Alternation in the heats of crystallization of the normal monobasic fatty acids. Part I., J. Chem. Soc., 1924, 125, 881-896. [all data]

Schaake, van Miltenburg, et al., 1982, 2
Schaake, R.C.F.; van Miltenburg, J.C.; De Kruif, C.G., Thermodynamic properties of the normal alkanoic acids. II. Molar heat capacities of seven even-numbered normal alkanoic acids., J. Chem. Thermodyn., 1982, 14, 771-8. [all data]

Andereya and Chase, 1990
Andereya, E.; Chase, J.D., Chem. Eng. Technol., 1990, 13, 304-12. [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]

D'Souza and Teja, 1987
D'Souza, R.; Teja, A.S., The prediction of the vapor pressures of carboxylic acids, Chem. Eng. Commun., 1987, 61, 13. [all data]

Verevkin, 2000
Verevkin, S.P., Measurement and Prediction of the Monocarboxylic Acids Thermochemical Properties, J. Chem. Eng. Data, 2000, 45, 5, 953-960, https://doi.org/10.1021/je990282m . [all data]

Chickos, Hosseini, et al., 1995
Chickos, James S.; Hosseini, Sarah; Hesse, Donald G., Determination of vaporization enthalpies of simple organic molecules by correlations of changes in gas chromatographic net retention times, Thermochimica Acta, 1995, 249, 41-62, https://doi.org/10.1016/0040-6031(95)90670-3 . [all data]

Kruif and Oonk, 1979
Kruif, C.G.; Oonk, H.A.J., Enthalpies of vaporization and vapour pressures of seven aliphatic carboxylic acids, J. Chem. Thermodyn., 1979, 11, 287-290. [all data]

Cappa, Lovejoy, et al., 2008
Cappa, Christopher D.; Lovejoy, Edward R.; Ravishankara, A.R., Evaporation Rates and Vapor Pressures of the Even-Numbered C ₈ -C ₁₈ Monocarboxylic Acids, J. Phys. Chem. A, 2008, 112, 17, 3959-3964, https://doi.org/10.1021/jp710586m . [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]

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]

de Kruif, Schaake, et al., 1982
de Kruif, C.G.; Schaake, R.C.F.; van Miltenburg, J.C.; van der Klauw, K.; Blok, J.G., Thermodynamic properties of the normal alkanoic acids III. Enthalpies of vaporization and vapour pressures of 13 normal alkanoic acids, The Journal of Chemical Thermodynamics, 1982, 14, 8, 791-798, https://doi.org/10.1016/0021-9614(82)90176-8 . [all data]

Cramer, 1943
Cramer, K.S.N., Chem. Zentr. II, 1943, 2234. [all data]

Rose, Acciarri, et al., 1957
Rose, Arthur.; Acciarri, Jerry A.; Johnson, R. Curtis.; Sanders, W.W., Automatic Computation of Antoine Equation 31 Constants---Caproic and Caprylic Acids and Methyl Esters, Ind. Eng. Chem., 1957, 49, 1, 104-109, https://doi.org/10.1021/ie50565a036 . [all data]

Domalski and Hearing, 1996
Domalski, Eugene S.; Hearing, Elizabeth D., Heat Capacities and Entropies of Organic Compounds in the Condensed Phase. Volume III, J. Phys. Chem. Ref. Data, 1996, 25, 1, 1, https://doi.org/10.1063/1.555985 . [all data]

Notes

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• Symbols used in this document:
  

  Cp,liquid	Constant pressure heat capacity of liquid
  Pc	Critical pressure
  Tboil	Boiling point
  Tc	Critical temperature
  Tfus	Fusion (melting) point
  Ttriple	Triple point temperature
  ΔHtrs	Enthalpy of phase transition
  ΔStrs	Entropy of phase transition
  ΔcH°liquid	Enthalpy of combustion 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
  ΔfusH	Enthalpy of fusion
  ΔfusS	Entropy of fusion
  ΔsubH°	Enthalpy of sublimation at standard conditions
  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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