Eicosanoic acid

• Formula: C₂₀H₄₀O₂
• Molecular weight: 312.5304
• IUPAC Standard InChI: InChI=1S/C20H40O2/c1-2-3-4-5-6-7-8-9-10-11-12-13-14-15-16-17-18-19-20(21)22/h2-19H2,1H3,(H,21,22) Copy

  
• IUPAC Standard InChIKey: VKOBVWXKNCXXDE-UHFFFAOYSA-N Copy
• CAS Registry Number: 506-30-9
• 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: Arachic acid; Arachidic acid; Icosanoic acid; n-Eicosanoic acid; Arachidic acid (synthetic)
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• Information on this page:
  • Condensed phase thermochemistry data
  • Phase change data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • References
  • Notes
• Other data available:
  • Gas Chromatography
• Data at other public NIST sites:
  • X-ray Photoelectron Spectroscopy Database, version 5.0
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Condensed phase thermochemistry data

Go To: Top, Phase change data, IR Spectrum, 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:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DH - Eugene S. Domalski and Elizabeth D. Hearing

Constant pressure heat capacity of solid

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:
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 sublimation

Enthalpy of fusion

Enthalpy of phase transition

Entropy of phase transition

IR Spectrum

Go To: Top, Condensed phase thermochemistry data, Phase change data, Mass spectrum (electron ionization), References, Notes

Data compiled by: Coblentz Society, Inc.

• SOLID (MINERAL OIL MULL); Not specified, most likely a prism, grating, or hybrid spectrometer.; DIGITIZED BY NIST FROM HARD COPY; 4 cm^-1 resolution

Data compiled by: NIST Mass Spectrometry Data Center, William E. Wallace, director

• gas

Mass spectrum (electron ionization)

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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: NIST Mass Spectrometry Data Center, William E. Wallace, director

Spectrum

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Additional Data

References

Go To: Top, Condensed phase thermochemistry data, Phase change data, IR Spectrum, 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.

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]

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]

Adriaanse, Dekker, et al., 1964
Adriaanse, N.; Dekker, H.; Coops, J., Some Physical Constants of Normal, Saturated Fatty Acids and Their Methyl Esters, Recl. Trav. Chim. Pays-Bas, 1964, 83, 557. [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]

Spizzichino, 1956
Spizzichino, C., Contribution a l'etude des tensions de vapeur et des chaleurs de vaporisation des acides gras, esters methyliques et alcools gras a des pressions inferieures a 1 mm de mercure, J. des Recherches du C.N.R.S., 1956, 34, 1-24. [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]

Chattopadhyay and Ziemann, 2005
Chattopadhyay, Sulekha; Ziemann, Paul J., Vapor Pressures of Substituted and Unsubstituted Monocarboxylic and Dicarboxylic Acids Measured Using an Improved Thermal Desorption Particle Beam Mass Spectrometry Method, Aerosol Science and Technology, 2005, 39, 11, 1085-1100, https://doi.org/10.1080/02786820500421547 . [all data]

Davies and Malpass, 1961
Davies, Mansel; Malpass, V.E., 212. Heats of sublimation of straight-chain monocarboxylic acids, J. Chem. Soc., 1961, 1048, https://doi.org/10.1039/jr9610001048 . [all data]

Cox and Pilcher, 1970
Cox, J.D.; Pilcher, G., Thermochemistry of Organic and Organometallic Compounds, Academic Press Inc., London, 1970, 643. [all data]

Davies and Malpass, 1961, 2
Davies, M.; Malpass, V.E., Heats of sublimation of straight-chain monocarboxylic acids, J. Chem. Soc., 1961, 1048-10. [all data]

Moreno, Cordobilla, et al., 2007
Moreno, Evelyn; Cordobilla, Raquel; Calvet, Teresa; Cuevas-Diarte, M.A.; Gbabode, Gabin; Negrier, Philippe; Mondieig, Denise; Oonk, Harry A.J., Polymorphism of even saturated carboxylic acids from n-decanoic to n-eicosanoic acid, New J. Chem., 2007, 31, 6, 947, https://doi.org/10.1039/b700551b . [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,solid	Constant pressure heat capacity of solid
  Ptriple	Triple point pressure
  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
  ΔfusH	Enthalpy of fusion
  ΔsubH	Enthalpy of sublimation
  ΔvapH	Enthalpy of vaporization

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