Benzoic acid
- Formula: C7H6O2
- Molecular weight: 122.1213
- IUPAC Standard InChIKey: WPYMKLBDIGXBTP-UHFFFAOYSA-N
- CAS Registry Number: 65-85-0
- 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: Benzenecarboxylic acid; Benzeneformic acid; Benzenemethanoic acid; Benzoesaeure GK; Benzoesaeure GV; Carboxybenzene; Dracylic acid; Phenylcarboxylic acid; Phenylformic acid; Retarder BA; Retardex; Salvo, liquid; Solvo, powder; Tenn-Plas; Acide benzoique; Benzoic acid, tech.; Kyselina benzoova; Benzoesaeure; Salvo powder; E 210; HA 1; HA 1 (acid); Phenylcarboxy; Benzenemethonic acid; Diacylic acid; Flowers of benjamin; Flowers of benzoin; Oracylic acid; Retarder BAX; NSC 149
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Gas phase thermochemistry data
Go To: Top, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering data, IR 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: Glushko Thermocenter, Russian Academy of Sciences, Moscow
Constant pressure heat capacity of gas
Cp,gas (J/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
103.47 | 298.15 | Stull D.R., 1969 | These values were calculated from preliminary assignment of vibrational frequencies. Statistical calculation [ Ali N., 1983] seems to be erroneous. |
104.01 | 300. | ||
138.36 | 400. | ||
170.54 | 500. | ||
196.73 | 600. | ||
217.82 | 700. | ||
234.89 | 800. | ||
248.95 | 900. | ||
260.66 | 1000. |
Reaction thermochemistry data
Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, Ion clustering data, IR 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:
B - John E. Bartmess
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
ALS - 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: C7H5O2- + H+ = C7H6O2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 1423. ± 9.2 | kJ/mol | G+TS | Fujio, McIver, et al., 1981 | gas phase; value altered from reference due to change in acidity scale; B |
ΔrH° | 1423. ± 12. | kJ/mol | G+TS | Cumming and Kebarle, 1978 | gas phase; Recalculated from data in paper; error in Table vs. ladder; B |
ΔrH° | 1423. ± 9.2 | kJ/mol | G+TS | Caldwell, Renneboog, et al., 1989 | gas phase; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 1393. ± 8.4 | kJ/mol | IMRE | Fujio, McIver, et al., 1981 | gas phase; value altered from reference due to change in acidity scale; B |
ΔrG° | 1393. ± 8.4 | kJ/mol | IMRE | Cumming and Kebarle, 1978 | gas phase; Recalculated from data in paper; error in Table vs. ladder; B |
ΔrG° | 1394. ± 8.4 | kJ/mol | IMRE | Caldwell, Renneboog, et al., 1989 | gas phase; B |
By formula: Br- + C7H6O2 = (Br- • C7H6O2)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 76.6 ± 7.5 | kJ/mol | IMRE | Paul and Kebarle, 1991 | gas phase; ΔGaff measured at 423 K, ΔSaff taken as that of PhNO2..Br-; B,M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 84. | J/mol*K | N/A | Paul and Kebarle, 1991 | gas phase; Entropy change calculated or estimated; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 41. ± 4.2 | kJ/mol | IMRE | Paul and Kebarle, 1991 | gas phase; ΔGaff measured at 423 K, ΔSaff taken as that of PhNO2..Br-; B |
Free energy of reaction
ΔrG° (kJ/mol) | T (K) | Method | Reference | Comment |
---|---|---|---|---|
41. | 423. | PHPMS | Paul and Kebarle, 1991 | gas phase; Entropy change calculated or estimated; M |
By formula: H2O + C7H5ClO = C7H6O2 + HCl
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -34.04 ± 0.21 | kJ/mol | Cm | Moselhy and Pritchard, 1975 | liquid phase; solvent: Diphenyl-ether; see Carson, Pritchard, et al., 1950 and Davies, Dunning, et al., 1972; ALS |
ΔrH° | -101.9 | kJ/mol | Cm | Carson, Pritchard, et al., 1950 | liquid phase; Heat of hydrolysis; ALS |
By formula: C7H6O + C7H6O3 = 2C7H6O2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -316. ± 13. | kJ/mol | Cm | Briner and Chastonay, 1954 | liquid phase; Reanalyzed by Cox and Pilcher, 1970, Original value = -317. ± 13. kJ/mol; ALS |
By formula: C7H5BrO + H2O = HBr + C7H6O2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -113.1 | kJ/mol | Cm | Carson, Pritchard, et al., 1950 | liquid phase; Heat of hydrolysis; ALS |
By formula: C7H5IO + H2O = HI + C7H6O2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -102.4 | kJ/mol | Cm | Carson, Pritchard, et al., 1950 | liquid phase; Heat of hydrolysis; ALS |
By formula: H2O + C8H8O2 = C7H6O2 + CH4O
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -73.0 ± 1.9 | kJ/mol | Eqk | Guthrie and Cullimore, 1980 | liquid phase; ALS |
Gas phase ion energetics data
Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Ion clustering data, IR 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
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
Proton affinity (review) | 821.1 | kJ/mol | N/A | Hunter and Lias, 1998 | HL |
Quantity | Value | Units | Method | Reference | Comment |
Gas basicity | 790.1 | kJ/mol | N/A | Hunter and Lias, 1998 | HL |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
9.3 | PE | Klasinc, Kovac, et al., 1983 | LBLHLM |
9.6 | PE | Meeks, Wahlborg, et al., 1981 | LLK |
9.8 ± 0.2 | EI | Benoit, 1973 | LLK |
9.75 | EI | Benoit, 1973, 2 | LLK |
9.73 ± 0.09 | EI | Foffani, Pignataro, et al., 1964 | RDSH |
9.47 | PE | Klasinc, Kovac, et al., 1983 | Vertical value; LBLHLM |
Appearance energy determinations
Ion | AE (eV) | Other Products | Method | Reference | Comment |
---|---|---|---|---|---|
C6H5+ | 14.3 ± 0.07 | ? | EI | Tajima, Azami, et al., 1977 | LLK |
C6H5+ | 15.1 ± 0.2 | CO+OH | EI | Benoit, 1973 | LLK |
C6H5+ | 15.08 | CO+OH | EI | Benoit, 1973, 2 | LLK |
C7H5O+ | 11.5 ± 0.07 | OH | EI | Tajima, Azami, et al., 1977 | LLK |
C7H5O+ | 12.1 ± 0.2 | OH | EI | Benoit, 1973 | LLK |
C7H5O+ | 12.11 | OH | EI | Benoit, 1973, 2 | LLK |
De-protonation reactions
By formula: C7H5O2- + H+ = C7H6O2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 1423. ± 9.2 | kJ/mol | G+TS | Fujio, McIver, et al., 1981 | gas phase; value altered from reference due to change in acidity scale; B |
ΔrH° | 1423. ± 12. | kJ/mol | G+TS | Cumming and Kebarle, 1978 | gas phase; Recalculated from data in paper; error in Table vs. ladder; B |
ΔrH° | 1423. ± 9.2 | kJ/mol | G+TS | Caldwell, Renneboog, et al., 1989 | gas phase; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 1393. ± 8.4 | kJ/mol | IMRE | Fujio, McIver, et al., 1981 | gas phase; value altered from reference due to change in acidity scale; B |
ΔrG° | 1393. ± 8.4 | kJ/mol | IMRE | Cumming and Kebarle, 1978 | gas phase; Recalculated from data in paper; error in Table vs. ladder; B |
ΔrG° | 1394. ± 8.4 | kJ/mol | IMRE | Caldwell, Renneboog, et al., 1989 | gas phase; B |
Ion clustering data
Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, IR 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:
B - John E. Bartmess
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. Searches may be limited to ion clustering reactions. A general reaction search form is also available.
Clustering reactions
By formula: Br- + C7H6O2 = (Br- • C7H6O2)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 76.6 ± 7.5 | kJ/mol | IMRE | Paul and Kebarle, 1991 | gas phase; ΔGaff measured at 423 K, ΔSaff taken as that of PhNO2..Br-; B,M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 84. | J/mol*K | N/A | Paul and Kebarle, 1991 | gas phase; Entropy change calculated or estimated; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 41. ± 4.2 | kJ/mol | IMRE | Paul and Kebarle, 1991 | gas phase; ΔGaff measured at 423 K, ΔSaff taken as that of PhNO2..Br-; B |
Free energy of reaction
ΔrG° (kJ/mol) | T (K) | Method | Reference | Comment |
---|---|---|---|---|
41. | 423. | PHPMS | Paul and Kebarle, 1991 | gas phase; Entropy change calculated or estimated; M |
IR Spectrum
Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering data, References, Notes
Data compiled by: Coblentz Society, Inc.
- SOLID (SPLIT MULL); DOW KBr FOREPRISM-GRATING; DIGITIZED BY COBLENTZ SOCIETY (BATCH I) FROM HARD COPY; 2 cm-1 resolution
- SOLID (VAPOR AT 160 C); DOW KBr FOREPRISM; DIGITIZED BY NIST FROM HARD COPY (FROM TWO SEGMENTS); 4 cm-1 resolution
- SOLUTION (2% CCl4 FOR 3800-1330, 2% CS2 FOR 1330-460 CM-1); DOW KBr FOREPRISM-GRATING; DIGITIZED BY COBLENTZ SOCIETY (BATCH I) FROM HARD COPY; 2 cm-1 resolution
- VAPOR AT 160 C; DOW KBr FOREPRISM-GRATING; DIGITIZED BY NIST FROM HARD COPY (FROM TWO SEGMENTS); 2 cm-1 resolution
Data compiled by: Timothy J. Johnson, Tanya L. Myers, Yin-Fong Su, Russell G. Tonkyn, Molly Rose K. Kelly-Gorham, and Tyler O. Danby
Data compiled by: NIST Mass Spectrometry Data Center, William E. Wallace, director
References
Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering data, IR Spectrum, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Stull D.R., 1969
Stull D.R., Jr.,
The Chemical Thermodynamics of Organic Compounds. Wiley, New York, 1969. [all data]
Ali N., 1983
Ali N.,
Thermodynamic functions of the benzoic acid, phthalic acid and salicylic acid,
Indian J. Phys., 1983, B57, 413-419. [all data]
Fujio, McIver, et al., 1981
Fujio, M.; McIver, R.T., Jr.; Taft, R.W.,
Effects on the acidities of phenols from specific substituent-solvent interactions. Inherent substituent parameters from gas phase acidities,
J. Am. Chem. Soc., 1981, 103, 4017. [all data]
Cumming and Kebarle, 1978
Cumming, J.B.; Kebarle, P.,
Summary of gas phase measurements involving acids AH. Entropy changes in proton transfer reactions involving negative ions. Bond dissociation energies D(A-H) and electron affinities EA(A),
Can. J. Chem., 1978, 56, 1. [all data]
Caldwell, Renneboog, et al., 1989
Caldwell, G.; Renneboog, R.; Kebarle, P.,
Gas Phase Acidities of Aliphatic Carboxylic Acids, Based on Measurements of Proton Transfer Equilibria,
Can. J. Chem., 1989, 67, 4, 661, https://doi.org/10.1139/v89-092
. [all data]
Paul and Kebarle, 1991
Paul, G.J.C.; Kebarle, P.,
Stabilities of Complexes of Br- with Substituted Benzenes (SB) Based on Determinations of the Gas-Phase Equilibria Br- + SB = (BrSB)-,
J. Am. Chem. Soc., 1991, 113, 4, 1148, https://doi.org/10.1021/ja00004a014
. [all data]
Moselhy and Pritchard, 1975
Moselhy, G.M.; Pritchard, H.O.,
The thermochemistry of the chloro-benzoyl chlorides,
J. Chem. Thermodyn., 1975, 7, 977-982. [all data]
Carson, Pritchard, et al., 1950
Carson, A.S.; Pritchard, H.O.; Skinner, H.A.,
The heats of hydrolysis of the benzoyl halides,
J. Chem. Soc., 1950, 656-659. [all data]
Davies, Dunning, et al., 1972
Davies, J.V.; Dunning, B.K.; Pritchard, H.O.,
The enthalpy of formation of benzoyl chloride,
J. Chem. Thermodyn., 1972, 4, 731-737. [all data]
Briner and Chastonay, 1954
Briner, E.; Chastonay, P.,
Etude thermochemique de l'autoxydation de Valdehyde benzoique,
Helv. Chim. Acta, 1954, 238, 539-541. [all data]
Cox and Pilcher, 1970
Cox, J.D.; Pilcher, G.,
Thermochemistry of Organic and Organometallic Compounds, Academic Press, New York, 1970, 1-636. [all data]
Guthrie and Cullimore, 1980
Guthrie, J.P.; Cullimore, P.A.,
Effect of the acyl substituent on the equilibrium constant for hydration of esters,
Can. J. Chem., 1980, 58, 1281-1294. [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]
Klasinc, Kovac, et al., 1983
Klasinc, L.; Kovac, B.; Gusten, H.,
Photoelectron spectra of acenes. Electronic structure and substituent effects,
Pure Appl. Chem., 1983, 55, 289. [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]
Benoit, 1973, 2
Benoit, F.,
The benzoyl cation: The participation of isolated electronic excited states in the dissociation of molecular ions of the form [C6H5COX]+,
Org. Mass Spectrom., 1973, 7, 1407. [all data]
Foffani, Pignataro, et al., 1964
Foffani, A.; Pignataro, S.; Cantone, B.; Grasso, F.,
Ionization potentials and substituent effects for aromatic carbonyl compounds,
Z. Physik. Chem. (Frankfurt), 1964, 42, 221. [all data]
Tajima, Azami, et al., 1977
Tajima, S.; Azami, T.; Tsuchiya, T.,
An investigation of the decomposition of the common intermediate ions produced by electron impact,
Org. Mass Spectrom., 1977, 12, 24. [all data]
Notes
Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering data, IR Spectrum, References
- Symbols used in this document:
AE Appearance energy Cp,gas Constant pressure heat capacity of gas T Temperature ΔrG° Free energy of reaction at standard conditions ΔrH° Enthalpy of reaction at standard conditions ΔrS° Entropy of reaction at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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