Benzoic acid, 4-methyl-

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Gas 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
DRB - Donald R. Burgess, Jr.

Quantity Value Units Method Reference Comment
Δfgas-330.4 ± 1.5kJ/molCcbColomina, Jimenez, et al., 1986see Colomina, Boned, et al., 1961; ALS
Δfgas-330.4kJ/molN/ACorral, 1960Value computed using ΔfHsolid° value of -429.2±1.1 kj/mol from Corral, 1960 and ΔsubH° value of 98.8 kj/mol from Colomina, Jimenez, et al., 1986.; DRB
Δfgas-324.5kJ/molN/ABreitenbach and Derkosch, 1951Value computed using ΔfHsolid° value of -423.3±3.8 kj/mol from Breitenbach and Derkosch, 1951 and ΔsubH° value of 98.8 kj/mol from Colomina, Jimenez, et al., 1986.; DRB

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

Quantity Value Units Method Reference Comment
Δfsolid-429.2 ± 1.5kJ/molCcbColomina, Jimenez, et al., 1986see Colomina, Boned, et al., 1961; ALS
Δfsolid-429.2 ± 1.1kJ/molCcbCorral, 1960Different experiments; ALS
Δfsolid-423.3 ± 3.8kJ/molCcbBreitenbach and Derkosch, 1951Reanalyzed by Cox and Pilcher, 1970, Original value = -422.6 kJ/mol; ALS
Quantity Value Units Method Reference Comment
Δcsolid-3862.3 ± 0.9kJ/molCcbColomina, Jimenez, et al., 1986see Colomina, Boned, et al., 1961; Corresponding Δfsolid = -429.1 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS
Δcsolid-3862.3 ± 0.92kJ/molCcbCorral, 1960Different experiments; Corresponding Δfsolid = -429.15 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS
Δcsolid-3868.kJ/molCcbBreitenbach and Derkosch, 1951Corresponding Δfsolid = -423.4 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS

Constant pressure heat capacity of solid

Cp,solid (J/mol*K) Temperature (K) Reference Comment
169.0298.Andrews, Lynn, et al., 1926T = 22 to 225 C.; 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:
BS - Robert L. Brown and Stephen E. Stein
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
AC - William E. Acree, Jr., James S. Chickos
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DRB - Donald R. Burgess, Jr.
DH - Eugene S. Domalski and Elizabeth D. Hearing

Quantity Value Units Method Reference Comment
Tboil547.7KN/AAldrich Chemical Company Inc., 1990BS
Quantity Value Units Method Reference Comment
Tfus455.KN/ASugunan and Thomas, 1993Uncertainty assigned by TRC = 2. K; TRC
Tfus450.15KN/AIpatieff, Corson, et al., 1936Uncertainty assigned by TRC = 2.5 K; TRC
Tfus452.8KN/AAndrews, Lynn, et al., 1926, 2Uncertainty assigned by TRC = 0.3 K; TRC
Quantity Value Units Method Reference Comment
Δsub98.6 ± 0.6kJ/molMEMonte, Almeida, et al., 2004Based on data from 320. to 337. K.; AC
Δsub98.8 ± 0.3kJ/molMEColomina, Jimenez, et al., 1986, 2Based on data from 318. to 337. K.; AC
Δsub98.8 ± 0.3kJ/molVColomina, Jimenez, et al., 1986see Colomina, Boned, et al., 1961; ALS
Δsub98.8kJ/molN/AColomina, Jimenez, et al., 1986DRB

Enthalpy of fusion

ΔfusH (kJ/mol) Temperature (K) Reference Comment
22.72452.8Acree, 1991AC
22.720452.8Andrews, Lynn, et al., 1926DH

Entropy of fusion

ΔfusS (J/mol*K) Temperature (K) Reference Comment
50.2452.8Andrews, Lynn, et al., 1926DH

In addition to the Thermodynamics Research Center (TRC) data available from this site, much more physical and chemical property data is available from the following TRC products:


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: 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

C8H7O2- + Hydrogen cation = Benzoic acid, 4-methyl-

By formula: C8H7O2- + H+ = C8H8O2

Quantity Value Units Method Reference Comment
Δr1427. ± 8.8kJ/molG+TSKebarle and McMahon, 1977gas phase
Δr1425. ± 8.8kJ/molG+TSDecouzon, Exner, et al., 1996gas phase; relative to benzoate at 333.0 kcal/mol
Quantity Value Units Method Reference Comment
Δr1397. ± 8.4kJ/molIMREKebarle and McMahon, 1977gas phase
Δr1396. ± 8.4kJ/molIMREDecouzon, Exner, et al., 1996gas phase; relative to benzoate at 333.0 kcal/mol

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 evaluated as indicated in comments:
HL - Edward P. Hunter and Sharon G. Lias

Data compiled as indicated in comments:
B - John E. Bartmess
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi

View reactions leading to C8H8O2+ (ion structure unspecified)

Quantity Value Units Method Reference Comment
Proton affinity (review)836.7kJ/molN/AHunter and Lias, 1998HL
Quantity Value Units Method Reference Comment
Gas basicity805.7kJ/molN/AHunter and Lias, 1998HL

Ionization energy determinations

IE (eV) Method Reference Comment
9.2 ± 0.2EIBenoit, 1973LLK
9.4PEMeeks, Wahlborg, et al., 1981Vertical value; LLK

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
C7H7+12.6 ± 0.2COOHEIBenoit, 1973LLK
C8H7O+12.1 ± 0.2OHEIBenoit, 1973LLK

De-protonation reactions

C8H7O2- + Hydrogen cation = Benzoic acid, 4-methyl-

By formula: C8H7O2- + H+ = C8H8O2

Quantity Value Units Method Reference Comment
Δr1427. ± 8.8kJ/molG+TSKebarle and McMahon, 1977gas phase; B
Δr1425. ± 8.8kJ/molG+TSDecouzon, Exner, et al., 1996gas phase; relative to benzoate at 333.0 kcal/mol; B
Quantity Value Units Method Reference Comment
Δr1397. ± 8.4kJ/molIMREKebarle and McMahon, 1977gas phase; B
Δr1396. ± 8.4kJ/molIMREDecouzon, Exner, et al., 1996gas phase; relative to benzoate at 333.0 kcal/mol; B

References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, Notes

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

Colomina, Jimenez, et al., 1986
Colomina, M.; Jimenez, P.; Roux, M.V.; Turrion, C., Propiedades termoquimicas de derivados del acido benzoico. XIII. Presiones de vapor y entalpias de sublimacion y formacion de los acidos toluicos, An. Quim., 1986, 82, 126-130. [all data]

Colomina, Boned, et al., 1961
Colomina, M.; Boned, M.L.; Turrion, C., Investigaciones termoquimicas sobre los acidos alquilbenzoicos. I. Acidos toluicos, An. Fis. Quim., 1961, 57, 655-664. [all data]

Corral, 1960
Corral, L.B., Investigaciones termoquimicas sobre los acidos toluicos y dimetilbenzoicos, Rev. R. Acad. Cienc., 1960, 54, 365-403. [all data]

Breitenbach and Derkosch, 1951
Breitenbach, J.W.; Derkosch, J., Verbrennungswarmen von peroxyden und verwandten verbindungen sowie von polystrolen, Monatsh. Chem., 1951, 82, 177-179. [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]

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]

Aldrich Chemical Company Inc., 1990
Aldrich Chemical Company Inc., Catalog Handbook of Fine Chemicals, Aldrich Chemical Company, Inc., Milwaukee WI, 1990, 1. [all data]

Sugunan and Thomas, 1993
Sugunan, S.; Thomas, B., Salting Coefficients of 2-, 3-, and 4-Methylbenzoic Acids, J. Chem. Eng. Data, 1993, 38, 520-1. [all data]

Ipatieff, Corson, et al., 1936
Ipatieff, V.N.; Corson, B.B.; Pines, H., Influence of Sulfuric Acid Concentration upon Reaction between Olefins and Benzene, J. Am. Chem. Soc., 1936, 58, 919-22. [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]

Monte, Almeida, et al., 2004
Monte, Manuel J.S.; Almeida, Ana R.R.P.; Ribeiro da Silva, Manuel A.V., Thermodynamic study of the sublimation of eight 4-n-alkylbenzoic acids, The Journal of Chemical Thermodynamics, 2004, 36, 5, 385-392, https://doi.org/10.1016/j.jct.2004.02.001 . [all data]

Colomina, Jimenez, et al., 1986, 2
Colomina, M.; Jimenez, P.; Roux, M.V.; Turrion, C., Propiedades termoquimicas de derivados del acido benzoico. XIII. Presiones de vapor y entalpias de sublimacion y formacion de los acidos toluicos, An. Quim., 1986, 82, 126. [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]

Decouzon, Exner, et al., 1996
Decouzon, M.; Exner, O.; Gal, J.-F.; Maria, P.-C., Non-classical Buttressing Effect: Gas-phase Ionization of Some Methyl Substituted Benzoic Acids, J. Chem. Soc. Perkin Trans., 1996, 2, 4, 475, https://doi.org/10.1039/p29960000475 . [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]

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]

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]


Notes

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, References