1,2-Benzenedicarboxylic acid

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

  
• IUPAC Standard InChIKey: XNGIFLGASWRNHJ-UHFFFAOYSA-N Copy
• CAS Registry Number: 88-99-3
• Chemical structure:
  This structure is also available as a 2d Mol file
• Other names: Phthalic acid; o-Benzenedicarboxylic acid; o-Dicarboxybenzene; Benzene-1,2-dicarboxylic acid; o-Phthalic acid; Acide phtalique; Kyselina ftalova; Sunftal 20; Orthophthalic acid
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• Information on this page:
  • Condensed phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
  • 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

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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 as indicated in comments:
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
AC - William E. Acree, Jr., James S. Chickos

Enthalpy of fusion

Reaction 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: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. A general reaction search form is also available. Future versions of this site may rely on reaction search pages in place of the enumerated reaction displays seen below.

Individual Reactions

=  + 

By formula: C₈H₆O₄ = H₂O + C₈H₄O₃

IR Spectrum

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Data compiled by: Coblentz Society, Inc.

• Not specified, most likely a prism, grating, or hybrid spectrometer.; (NO SPECTRUM, ONLY SCANNED IMAGE IS AVAILABLE)
• SOLID (MINERAL OIL MULL); Not specified, most likely a prism, grating, or hybrid spectrometer.; DIGITIZED BY NIST FROM HARD COPY; 4 cm^-1 resolution

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

UV/Visible spectrum

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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: Victor Talrose, Alexander N. Yermakov, Alexy A. Usov, Antonina A. Goncharova, Axlexander N. Leskin, Natalia A. Messineva, Natalia V. Trusova, Margarita V. Efimkina

Spectrum

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Additional Data

References

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

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

Parks, Mosley, et al., 1950
Parks, G.S.; Mosley, J.R.; Peterson, P.V., Jr., Heats of combustion and formation of some organic compounds containing oxygen, J. Chem. Phys., 1950, 18, 152. [all data]

Richardson and Parks, 1939
Richardson, J.W.; Parks, G.S., Thermal data on organic compounds. XIX. Modern combustion data for some non-volatile compounds containing carbon, hydrogen and oxygen, J. Am. Chem. Soc., 1939, 61, 3543-3546. [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]

Parks, Todd, et al., 1936
Parks, G.S.; Todd, S.S.; Moore, W.A., Thermal data on organic compounds. XVI. Some heat capacity, entropy and free energy data for typical benzene derivatives and heterocyclic compounds, J. Am. Chem. Soc., 1936, 58, 398-401. [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]

Parks, Todd, et al., 1936, 2
Parks, G.S.; Todd, S.S.; Shomate, C.H., Thermal data on organic compounds. XVII. Some heat capacity, entropy and free energy data for five higher olefins, J. Am. Chem. Soc., 1936, 58, 2505. [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]

Alekseev, Kizaev, et al., 1989
Alekseev, V.G.; Kizaev, V.D.; Fedyainov, N.V.; Bushinskii, V.I., Standard enthalpies of anhydridisation of phthalic and pyromellitic acids, Russ. J. Phys. Chem. (Engl. Transl.), 1989, 63, 1280-1282. [all data]

Lang (editor), 1971
Lang (editor), L., Absorption Spectra in the Ultraviolet and Visible Region, 1971, 15, 81. [all data]

Notes

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• Symbols used in this document:
  

  Cp,solid	Constant pressure heat capacity of solid
  S°solid,1 bar	Entropy of solid at standard conditions (1 bar)
  Tfus	Fusion (melting) point
  ΔcH°solid	Enthalpy of combustion of solid at standard conditions
  ΔfH°solid	Enthalpy of formation of solid at standard conditions
  ΔfusH	Enthalpy of fusion
  ΔrH°	Enthalpy of reaction at standard conditions
  ΔsubH°	Enthalpy of sublimation at standard conditions

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