1,2-Benzenedicarboxylic acid
- Formula: C8H6O4
- Molecular weight: 166.1308
- IUPAC Standard InChIKey: XNGIFLGASWRNHJ-UHFFFAOYSA-N
- 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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Condensed phase thermochemistry data
Go To: Top, Phase change data, Reaction thermochemistry 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:
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 |
---|---|---|---|---|---|
ΔfH°solid | -186.93 | kcal/mol | Ccb | Schwabe and Wagner, 1961 | ALS |
ΔfH°solid | -186.88 | kcal/mol | Ccb | Parks, Mosley, et al., 1950 | see Richardson and Parks, 1939; ALS |
Quantity | Value | Units | Method | Reference | Comment |
ΔcH°solid | -770.44 ± 0.12 | kcal/mol | Ccb | Schwabe and Wagner, 1961 | Corresponding ΔfHºsolid = -186.91 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS |
ΔcH°solid | -770.49 | kcal/mol | Ccb | Parks, Mosley, et al., 1950 | see Richardson and Parks, 1939; Corresponding ΔfHºsolid = -186.86 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS |
ΔcH°solid | -771.979 | kcal/mol | Ccb | Verkade, 1926 | Corresponding ΔfHºsolid = -185.38 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS |
Quantity | Value | Units | Method | Reference | Comment |
S°solid,1 bar | 49.699 | cal/mol*K | N/A | Parks, Todd, et al., 1936 | Extrapolation below 90 K, 66.19 J/mol*K.; DH |
Constant pressure heat capacity of solid
Cp,solid (cal/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
48.21 | 323. | Satoh and Sogabe, 1941 | T = 0 to 100 C. Mean value.; DH |
48.21 | 323. | Satoh and Sogabe, 1939 | T = 0 to 100 C. Mean value.; DH |
44.959 | 298.1 | Parks, Todd, et al., 1936 | T = 90 to 300 K.; DH |
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
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
Tfus | 480. | K | N/A | Parks, Todd, et al., 1936, 2 | Uncertainty assigned by TRC = 3. K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
ΔsubH° | 31.0 ± 0.1 | kcal/mol | C | Sabbah and Perez, 1999 | AC |
Enthalpy of fusion
ΔfusH (kcal/mol) | Temperature (K) | Reference | Comment |
---|---|---|---|
8.72 | 463.5 | Sabbah and Perez, 1999 | AC |
Reaction thermochemistry data
Go To: Top, Condensed phase thermochemistry data, 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 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
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 7.631 ± 0.069 | kcal/mol | Cm | Alekseev, Kizaev, et al., 1989 | solid phase; solvent: Aqueous; Enthapy of anhydridisation |
References
Go To: Top, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Notes
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]
Notes
Go To: Top, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, References
- 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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