Isophthalic acid

• Formula: C₈H₆O₄
• Molecular weight: 166.1308
• IUPAC Standard InChI: InChI=1S/C8H6O4/c9-7(10)5-2-1-3-6(4-5)8(11)12/h1-4H,(H,9,10)(H,11,12) Copy

  
• IUPAC Standard InChIKey: QQVIHTHCMHWDBS-UHFFFAOYSA-N Copy
• CAS Registry Number: 121-91-5
• 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: 1,3-Benzenedicarboxylic acid; m-Benzenedicarboxylic acid; m-Phthalic acid; Benzene,1,3-dicarboxylic acid; Acide isophtalique; Kyselina isoftalova; IPA; m-Dicarboxybenzene; NSC 15310
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• Information on this page:
  • Condensed phase thermochemistry data
  • Phase change data
  • Gas phase ion energetics data
  • Mass spectrum (electron ionization)
  • References
  • Notes
• Other data available:
  • IR Spectrum
  • UV/Visible spectrum
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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:
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 by: William E. Acree, Jr., James S. Chickos

Enthalpy of sublimation

Enthalpy of fusion

Gas phase ion energetics 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: Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi

Ionization energy determinations

Appearance energy determinations

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, 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.

Karyakin, Rabinovich, et al., 1978
Karyakin, N.V.; Rabinovich, I.B.; Sokolov, L.B., Thermodynamics of the synthesis of isomeric poly(phenylenephthalamides), Vysokomol. Soedin. Ser. B, 1978, 20, 662-666. [all data]

Karyakin, Rabinovich, et al., 1975
Karyakin, N.V.; Rabinovich, I.B.; Kamelova, G.P.; Mochalov, A.N.; Tseitlin, G.M.; Kulagin, V.N.; Korshak, V.V., Thermodynamics of the synthesis of poly-2,2'-(m-phenylene)-5-5'-dibenzoxazolomethane, Polym. Sci. USSR, 1975, 17, 1127-1133. [all data]

Karyakin, Kamelova, et al., 1973
Karyakin, N.V.; Kamelova, G.P.; Yurchenko, V.N.; Kiparisova, e.G.; Korshak, V.V.; Tseitlin, G.M.; Kulagin, V.N.; Rabinovich, I.B., Thermodynamics of the synthesis of poly[2,2'-(m-phenylene)-5,5'-dibenzoxazolemethane] from 3,3'-diamino-4,4'-dihydroxydiphenylmethane and isophthalic acid, Tr. Khim. Khim. Tekhnol., 1973, 71-72. [all data]

Schwabe and Wagner, 1961
Schwabe, K.; Wagner, W., Verbrennungs- und bildungswarmen der drei isomeren phthalsauren, Z. Electrochem., 1961, 65, 812-815. [all data]

Verkade, Coops, et al., 1928
Verkade, P.E.; Coops, J., Jr.; Maan, Chr.J., Calorimetrische Untersuchungen. XV. Thermochemische studien uber cycloparaffine und ihre derivate: 1. Experimentelle daten fur funf- und sechsgliedrige cyclische diole, Ann., 1928, 467, 217-239. [all data]

Verkade, 1926
Verkade, P.E., Verbrandingswarmten van plaatsings-isomere benzol-derivaten en de theorie der geinduceerde alterneeren de polatiteit, Verslag Akad. Wetenschappen Amsterdam, 1926, 35, 492-504. [all data]

Satoh and Sogabe, 1941
Satoh, S.; Sogabe, T., The heat capacities of some organic compounds containing nitrogen and the atomic heat of nitrogen. (4), Sci., Pap. Inst. Phys. Chem. Res. (Tokyo), 1941, 38, 246-251. [all data]

Satoh and Sogabe, 1939
Satoh, S.; Sogabe, T., The specific heats of some solid aromatic acids and their ammonium salts and the atomic heat of nitrogen, Sci. Pap. Inst. Phys. Chem. Res. (Tokyo), 1939, 36, 449-457. [all data]

Sabbah and Perez, 1999
Sabbah, Raphaël; Perez, Laurence, Étude thermodynamique des acides phtalique, isophtalique et téréphtalique, Revue canadienne de chimie, 1999, 77, 9, 1508-1513, https://doi.org/10.1139/cjc-77-9-1508 . [all data]

Kozyro, Maksimuk, et al., 2000
Kozyro, A.A.; Maksimuk, Yu.V.; Kabo, G.Ya., Thermodynamics of vaporization of phthalic acids and additivity of enthalpies and entropies of sublimation of benzocarboxylic acids, Zh. Prikl. Khim. (S.-Peterburg), 2000, 73, 2, 199. [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]

Kraus, Beranek, et al., 1962
Kraus, M.; Beranek, L.; Kochloeff, K.; Bazant, V., Chem. Prum., 1962, 12, 649. [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]

Benoit, 1973
Benoit, F., Substituent effects in mass spectrometry. III. Substituent effects in the dissociation of the molecular ions of para and meta subtituted benzoic acids, Org. Mass Spectrom., 1973, 7, 295. [all data]

Notes

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• Symbols used in this document:
  

  AE	Appearance energy
  Cp,solid	Constant pressure heat capacity of solid
  ΔcH°solid	Enthalpy of combustion of solid at standard conditions
  ΔfH°solid	Enthalpy of formation of solid at standard conditions
  ΔfusH	Enthalpy of fusion
  ΔsubH	Enthalpy of sublimation
  ΔsubH°	Enthalpy of sublimation at standard conditions

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