4-Aminobenzoic acid
- Formula: C7H7NO2
- Molecular weight: 137.1360
- IUPAC Standard InChIKey: ALYNCZNDIQEVRV-UHFFFAOYSA-N
- CAS Registry Number: 150-13-0
- 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: p-Aminobenzoic acid; Aminobenzoic Acid; Benzoic acid, 4-amino-; Benzoic acid, p-amino-; p-Carboxyaniline; p-Carboxyphenylamine; Amben; anti-Chromotrichia Factor; Anticanitic vitamin; Chromotrichia factor; Hachemina; Pabacyd; Pabafilm; Pabamine; Paraminol; Paranate; PAB; PABA; Trichochromogenic Factor; Vitamin BX; Vitamin H'; 4-Carboxyaniline; γ-Aminobenzoic acid; Aminobenzoic acid, para; Bacterial vitamin H1; Pabanol; Super Shade by Coppertone; 1-Amino-4-carboxybenzene; Kyselina p-aminobenzoova; Sunbrella; RVPaba Lipstick; para-Aminobenzoic acid; Romavit; Aniline-4-carboxylic acid; Anticantic vitamin; Pabagel; component of Presun; 8014-65-1; component of Presun (Salt/Mix)
- Permanent link for this species. Use this link for bookmarking this species for future reference.
- Information on this page:
- Other data available:
- Data at other public NIST sites:
- Options:
Data at NIST subscription sites:
NIST subscription sites provide data under the NIST Standard Reference Data Program, but require an annual fee to access. The purpose of the fee is to recover costs associated with the development of data collections included in such sites. Your institution may already be a subscriber. Follow the links above to find out more about the data in these sites and their terms of usage.
Gas phase thermochemistry data
Go To: Top, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), UV/Visible spectrum, 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
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔfH°gas | -70.24 ± 0.98 | kcal/mol | Ccr | Nabavian, Sabbah, et al., 1977 | Author was aware that data differs from previously reported values |
Condensed phase thermochemistry data
Go To: Top, Gas phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), UV/Visible spectrum, 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 | -97.99 ± 0.41 | kcal/mol | Ccr | Nabavian, Sabbah, et al., 1977 | Author was aware that data differs from previously reported values; ALS |
ΔfH°solid | -98.8 ± 0.1 | kcal/mol | Ccb | Lebedeva, Gutner, et al., 1971 | Hfusion=5.0±0.1, see Lebedeva, Rjadnenko, et al., 1969; ALS |
ΔfH°solid | -78.47 | kcal/mol | Ccb | Pushkareva and Kokoshko, 1946 | Author's hf298_condensed=-81.5 kcal/mol, used C as diamond; ALS |
Quantity | Value | Units | Method | Reference | Comment |
ΔcH°solid | -799.47 ± 0.35 | kcal/mol | Ccr | Nabavian, Sabbah, et al., 1977 | Author was aware that data differs from previously reported values; ALS |
ΔcH°solid | -798.7 ± 0.1 | kcal/mol | Ccb | Lebedeva, Gutner, et al., 1971 | Hfusion=5.0±0.1, see Lebedeva, Rjadnenko, et al., 1969; ALS |
ΔcH°solid | -819.0 | kcal/mol | Ccb | Pushkareva and Kokoshko, 1946 | Author's hf298_condensed=-81.5 kcal/mol, used C as diamond; ALS |
Constant pressure heat capacity of solid
Cp,solid (cal/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
44.79 | 323. | Satoh and Sogabe, 1941 | T = 0 to 100 C. Mean value.; DH |
42.50 | 298. | Andrews, Lynn, et al., 1926 | T = 22 to 190 C.; DH |
Phase change data
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), UV/Visible spectrum, 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:
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
AC - William E. Acree, Jr., James S. Chickos
DH - Eugene S. Domalski and Elizabeth D. Hearing
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
Tfus | 461.4 | K | N/A | Andrews, Lynn, et al., 1926, 2 | Uncertainty assigned by TRC = 0.6 K; with some decomposition; TRC |
Quantity | Value | Units | Method | Reference | Comment |
ΔsubH° | 27.75 ± 0.88 | kcal/mol | V | Nabavian, Sabbah, et al., 1977 | Author was aware that data differs from previously reported values; ALS |
ΔsubH° | 27.75 ± 0.88 | kcal/mol | V | Sabbah, Chastelet, et al., 1974 | ALS |
ΔsubH° | 27.7 ± 0.88 | kcal/mol | C | Sabbah, Chastel, et al., 1974 | See also Nabavian, Sabbah, et al., 1977, 2.; AC |
Enthalpy of sublimation
ΔsubH (kcal/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
26.8 ± 0.2 | 373. | TE | de Kruif, Voogd, et al., 1979 | AC |
27.2 ± 0.84 | 367. to 389. | C | Sabbah, Chastel, et al., 1974 | AC |
Enthalpy of fusion
ΔfusH (kcal/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
5.406 | 458.7 | DSC | Gracin and Rasmuson, 2004 | AC |
5.86 | 459.2 | N/A | Rotich, Glass, et al., 2001 | AC |
5.000 | 461.4 | N/A | Acree, 1991 | AC |
5.0000 | 461.4 | N/A | Andrews, Lynn, et al., 1926 | DH |
Entropy of fusion
ΔfusS (cal/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
10.8 | 461.4 | Andrews, Lynn, et al., 1926 | DH |
Reaction thermochemistry data
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), UV/Visible spectrum, 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: John E. Bartmess
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
C7H6NO2- + =
By formula: C7H6NO2- + H+ = C7H7NO2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 343.4 ± 2.1 | kcal/mol | G+TS | Kebarle and McMahon, 1977 | gas phase |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 336.4 ± 2.0 | kcal/mol | IMRE | Kebarle and McMahon, 1977 | gas phase |
Gas phase ion energetics data
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, IR Spectrum, Mass spectrum (electron ionization), UV/Visible spectrum, References, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Data evaluated as indicated in comments:
HL - Edward P. Hunter and Sharon G. Lias
Data compiled as indicated in comments:
B - John E. Bartmess
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
View reactions leading to C7H7NO2+ (ion structure unspecified)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
Proton affinity (review) | 206.7 | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
Quantity | Value | Units | Method | Reference | Comment |
Gas basicity | 198.9 | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
8.3 | EI | Tobita, Tajima, et al., 1984 | LBLHLM |
7.8 | PE | Meeks, Wahlborg, et al., 1981 | LLK |
8.4 ± 0.2 | EI | Benoit, 1973 | LLK |
8.4 | PE | Meeks, Wahlborg, et al., 1981 | Vertical value; LLK |
Appearance energy determinations
Ion | AE (eV) | Other Products | Method | Reference | Comment |
---|---|---|---|---|---|
C6H6N+ | 14.8 ± 0.2 | CO+OH | EI | Benoit, 1973 | LLK |
C7H6NO+ | 12.1 ± 0.2 | OH | EI | Benoit, 1973 | LLK |
De-protonation reactions
C7H6NO2- + =
By formula: C7H6NO2- + H+ = C7H7NO2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 343.4 ± 2.1 | kcal/mol | G+TS | Kebarle and McMahon, 1977 | gas phase; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 336.4 ± 2.0 | kcal/mol | IMRE | Kebarle and McMahon, 1977 | gas phase; B |
IR Spectrum
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, Mass spectrum (electron ionization), UV/Visible spectrum, References, Notes
Data compiled by: Coblentz Society, Inc.
Data compiled by: NIST Mass Spectrometry Data Center, William E. Wallace, director
Mass spectrum (electron ionization)
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, IR Spectrum, UV/Visible spectrum, 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: NIST Mass Spectrometry Data Center, William E. Wallace, director
Spectrum
Notice: This spectrum may be better viewed with a Javascript and HTML 5 enabled browser.
Additional Data
View image of digitized spectrum (can be printed in landscape orientation).
Due to licensing restrictions, this spectrum cannot be downloaded.
Owner | NIST Mass Spectrometry Data Center Collection (C) 2014 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved. |
---|---|
Origin | NIST Mass Spectrometry Data Center, 1990. |
NIST MS number | 118372 |
UV/Visible spectrum
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics 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 by: Victor Talrose, Eugeny B. Stern, Antonina A. Goncharova, Natalia A. Messineva, Natalia V. Trusova, Margarita V. Efimkina
Spectrum
Notice: This spectrum may be better viewed with a Javascript and HTML 5 enabled browser.
Additional Data
View image of digitized spectrum (can be printed in landscape orientation).
View spectrum image in SVG format.
Download spectrum in JCAMP-DX format.
Source | Grammaticakis, 1951 |
---|---|
Owner | INEP CP RAS, NIST OSRD Collection (C) 2007 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved. |
Origin | INSTITUTE OF ENERGY PROBLEMS OF CHEMICAL PHYSICS, RAS |
Source reference | RAS UV No. 409 |
Instrument | n.i.g. |
Melting point | 188.5 |
References
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), UV/Visible spectrum, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Nabavian, Sabbah, et al., 1977
Nabavian, P.M.; Sabbah, R.; Chastel, R.; Laffitte, M.,
Thermodynamique de composes azotes. II. Etude thermochimique des acides aminobenzoiques, de la pyrimidine, de l'uracile et de la thymine.,
J. Chim. Phys., 1977, 74, 115-126. [all data]
Lebedeva, Gutner, et al., 1971
Lebedeva, N.D.; Gutner, N.M.; Ryadnenko, V.L.,
Heats of combustion and formation of certain aromatic amino-derivatives,
Russ. J. Phys. Chem. (Engl. Transl.), 1971, 45, 561-562. [all data]
Lebedeva, Rjadnenko, et al., 1969
Lebedeva, N.D.; Rjadnenko, B.L.; Gutner, N.M.,
Heats of formation of some N-containing organic compounds,
Int. Conf. Calorim. Therm. (Warsaw, Poland), 1969, 1-8. [all data]
Pushkareva and Kokoshko, 1946
Pushkareva, Z.V.; Kokoshko, Z.U.,
On the question of the relation between the structure and bacteriostatic activity of sulphanilamide compounds. I. The resonance energy of some sulphanilamide compounds,
Zh. Obshch. Kim., 1946, 16, 1269-1278. [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. (2), Sci.,
Pap. Inst. Phys. Chem. Res. (Tokyo), 1941, 38, 231-237. [all data]
Andrews, Lynn, et al., 1926
Andrews, D.H.; Lynn, G.; Johnston, J.,
The heat capacities and heat of crystallization of some isomeric aromatic compounds,
J. Am. Chem. Soc., 1926, 48, 1274-1287. [all data]
Andrews, Lynn, et al., 1926, 2
Andrews, D.H.; Lynn, G.; Johnston, J.,
The Heat Capacities and Heat of Crystallization of Some Isomeric Aromatic Compounds,
J. Am. Chem. Soc., 1926, 48, 1274. [all data]
Sabbah, Chastelet, et al., 1974
Sabbah, R.; Chastelet, R.; Laffitte, M.,
Thermodynamic de composès azotes. I. Etude calorimètrique des enthalpies de sublimation des trios acides aminobenzoïques,
Can. J. Chem., 1974, 52, 2201. [all data]
Sabbah, Chastel, et al., 1974
Sabbah, Raphaël; Chastel, Raymond; Laffitte, Marc,
Thermodynamique de composés azotés. I. Etude calorimétrique des enthalpies de sublimation des trois acides aminobenzoïques,
Can. J. Chem., 1974, 52, 12, 2201-2205, https://doi.org/10.1139/v74-319
. [all data]
Nabavian, Sabbah, et al., 1977, 2
Nabavian, M.; Sabbah, R.; Chastel, R.; Laffitte, M.,
J. Chim. Phys.Phys.-Chim. Biol., 1977, 74, 115. [all data]
de Kruif, Voogd, et al., 1979
de Kruif, C.G.; Voogd, J.; Offringa, J.C.A.,
Enthalpies of sublimation and vapour pressures of 14 amino acids and peptides,
The Journal of Chemical Thermodynamics, 1979, 11, 7, 651-656, https://doi.org/10.1016/0021-9614(79)90030-2
. [all data]
Gracin and Rasmuson, 2004
Gracin, Sandra; Rasmuson, Åke C.,
Polymorphism and Crystallization of p -Aminobenzoic Acid,
Crystal Growth & Design, 2004, 4, 5, 1013-1023, https://doi.org/10.1021/cg049954h
. [all data]
Rotich, Glass, et al., 2001
Rotich, M.K.; Glass, B.D.; Brown, M.E.,
Journal of Thermal Analysis and Calorimetry, 2001, 64, 2, 681-688, https://doi.org/10.1023/A:1011584125859
. [all data]
Acree, 1991
Acree, William E.,
Thermodynamic properties of organic compounds: enthalpy of fusion and melting point temperature compilation,
Thermochimica Acta, 1991, 189, 1, 37-56, https://doi.org/10.1016/0040-6031(91)87098-H
. [all data]
Kebarle and McMahon, 1977
Kebarle, P.; McMahon, T.B.,
Intrinsic Acidities of Substituted Phenols and Benzoic Acids Determined by Gas Phase Proton Transfer Equilibria,
J. Am. Chem. Soc., 1977, 99, 7, 2222, https://doi.org/10.1021/ja00449a032
. [all data]
Hunter and Lias, 1998
Hunter, E.P.; Lias, S.G.,
Evaluated Gas Phase Basicities and Proton Affinities of Molecules: An Update,
J. Phys. Chem. Ref. Data, 1998, 27, 3, 413-656, https://doi.org/10.1063/1.556018
. [all data]
Tobita, Tajima, et al., 1984
Tobita, S.; Tajima, S.; Tsuchiya, T.,
The substituent effect on the single and double hydrogen atom transfer reactions in para-substituted benzoic acid isobutyl esters,
Org. Mass Spectrom., 1984, 19, 326. [all data]
Meeks, Wahlborg, et al., 1981
Meeks, J.; Wahlborg, A.; McGlynn, S.P.,
Photoelectron spectroscopy of carbonyls: Benzoic acid and its derivatives,
J. Electron Spectrosc. Relat. Phenom., 1981, 22, 43. [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]
Grammaticakis, 1951
Grammaticakis, P.,
Contribution a l'etude de l'absorption dans l'ultraviolet moyen et le visible des arylamines isomeres et de leurs derives N substitues (Premier memoire),
Bull. Soc. Chim. Fr., 1951, 18, 220-226. [all data]
Notes
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), UV/Visible spectrum, References
- Symbols used in this document:
AE Appearance energy Cp,solid Constant pressure heat capacity of solid Tfus Fusion (melting) point ΔcH°solid Enthalpy of combustion of solid at standard conditions ΔfH°gas Enthalpy of formation of gas at standard conditions ΔfH°solid Enthalpy of formation of solid at standard conditions ΔfusH Enthalpy of fusion ΔfusS Entropy of fusion ΔrG° Free energy of reaction at standard conditions ΔrH° Enthalpy of reaction at standard conditions ΔsubH Enthalpy of sublimation ΔsubH° Enthalpy of sublimation at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
- The National Institute of Standards and Technology (NIST) uses its best efforts to deliver a high quality copy of the Database and to verify that the data contained therein have been selected on the basis of sound scientific judgment. However, NIST makes no warranties to that effect, and NIST shall not be liable for any damage that may result from errors or omissions in the Database.
- Customer support for NIST Standard Reference Data products.