Benzoic acid, 2-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-320.6 ± 1.5kJ/molCcbColomina, Jimenez, et al., 1986see Colomina, Boned, et al., 1961 and Colomina, Perez Ossorio, et al., 1959; ALS
Δfgas-320.6kJ/molN/ACorral, 1960Value computed using ΔfHsolid° value of -416.5±0.9 kj/mol from Corral, 1960 and ΔsubH° value of 95.9 kj/mol from Colomina, Jimenez, et al., 1986.; DRB
Δfgas-331.2kJ/molN/ABreitenbach and Derkosch, 1951Value computed using ΔfHsolid° value of -427.1±3.8 kj/mol from Breitenbach and Derkosch, 1951 and ΔsubH° value of 95.9 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-416.5 ± 1.5kJ/molCcbColomina, Jimenez, et al., 1986see Colomina, Boned, et al., 1961 and Colomina, Perez Ossorio, et al., 1959; ALS
Δfsolid-416.5 ± 0.92kJ/molCcbCorral, 1960ALS
Δfsolid-427.1 ± 3.8kJ/molCcbBreitenbach and Derkosch, 1951Reanalyzed by Cox and Pilcher, 1970, Original value = -426.3 kJ/mol; ALS
Quantity Value Units Method Reference Comment
Δcsolid-3874.9 ± 0.8kJ/molCcbColomina, Jimenez, et al., 1986see Colomina, Boned, et al., 1961 and Colomina, Perez Ossorio, et al., 1959; Corresponding Δfsolid = -416.5 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS
Δcsolid-3874.4 ± 4.6kJ/molCcbHoldiness, 1983Corresponding Δfsolid = -417.0 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS
Δcsolid-3875.0 ± 0.75kJ/molCcbCorral, 1960Corresponding Δfsolid = -416.4 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS
Δcsolid-3864.kJ/molCcbBreitenbach and Derkosch, 1951Corresponding Δfsolid = -427.2 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS
Δcsolid-3858.kJ/molCcbAuwers and Roth, 1910Corresponding Δfsolid = -433.9 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
174.9298.Andrews, Lynn, et al., 1926T = 22 to 200 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
Tboil531.7KN/AAldrich Chemical Company Inc., 1990BS
Quantity Value Units Method Reference Comment
Tfus380.KN/ASugunan and Thomas, 1993Uncertainty assigned by TRC = 1.5 K; TRC
Tfus376.50KN/ADomanska and Hofman, 1985Uncertainty assigned by TRC = 0.05 K; TRC
Tfus377.65KN/ADoering and Bragole, 1966Uncertainty assigned by TRC = 2. K; TRC
Tfus376.9KN/AAndrews, Lynn, et al., 1926, 2Uncertainty assigned by TRC = 0.3 K; TRC
Quantity Value Units Method Reference Comment
Δsub95.9 ± 0.1kJ/molMEColomina, Jimenez, et al., 1986, 2Based on data from 297. to 337. K.; AC
Δsub95.9 ± 0.1kJ/molVColomina, Jimenez, et al., 1986see Colomina, Boned, et al., 1961 and Colomina, Perez Ossorio, et al., 1959; ALS
Δsub95.9kJ/molN/AColomina, Jimenez, et al., 1986DRB

Enthalpy of fusion

ΔfusH (kJ/mol) Temperature (K) Reference Comment
20.17376.9Acree, 1991AC
20.170376.9Andrews, Lynn, et al., 1926DH

Entropy of fusion

ΔfusS (J/mol*K) Temperature (K) Reference Comment
53.5376.9Andrews, 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, 2-methyl-

By formula: C8H7O2- + H+ = C8H8O2

Quantity Value Units Method Reference Comment
Δr1419. ± 9.2kJ/molG+TSKebarle and McMahon, 1977gas phase
Quantity Value Units Method Reference Comment
Δr1390. ± 8.4kJ/molIMREKebarle and McMahon, 1977gas phase
Δr1391. ± 8.4kJ/molIMREDecouzon, Ertl, et al., 1993gas phase

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)838.8kJ/molN/AHunter and Lias, 1998HL
Quantity Value Units Method Reference Comment
Gas basicity807.8kJ/molN/AHunter and Lias, 1998HL

Ionization energy determinations

IE (eV) Method Reference Comment
9.1PEMeeks, Wahlborg, et al., 1981LLK
9.4PEMeeks, Wahlborg, et al., 1981Vertical value; LLK

De-protonation reactions

C8H7O2- + Hydrogen cation = Benzoic acid, 2-methyl-

By formula: C8H7O2- + H+ = C8H8O2

Quantity Value Units Method Reference Comment
Δr1419. ± 9.2kJ/molG+TSKebarle and McMahon, 1977gas phase; B
Quantity Value Units Method Reference Comment
Δr1390. ± 8.4kJ/molIMREKebarle and McMahon, 1977gas phase; B
Δr1391. ± 8.4kJ/molIMREDecouzon, Ertl, et al., 1993gas phase; B

IR 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: NIST Mass Spectrometry Data Center, William E. Wallace, director

Gas Phase Spectrum

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IR spectrum
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Additional Data

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Owner NIST Standard Reference Data Program
Collection (C) 2018 copyright by the U.S. Secretary of Commerce
on behalf of the United States of America. All rights reserved.
Origin Sadtler Research Labs Under US-EPA Contract
State gas

This IR spectrum is from the NIST/EPA Gas-Phase Infrared Database .


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, 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

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Mass spectrum
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Additional Data

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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, 1998.
NIST MS number 290981

All mass spectra in this site (plus many more) are available from the NIST/EPA/NIH Mass Spectral Library. Please see the following for information about the library and its accompanying search program.


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), 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]

Colomina, Perez Ossorio, et al., 1959
Colomina, M.; Perez Ossorio, R.; Boned, M.L.; Panea, M.; Turrion, C., Thermochemical investigations on methylsubstituted benzoic acids, Rpt. for the U.S. Dept. of the Army, European Research Office contract no. DA-91-508-EUC-358 by Instituto de Quimica Fisica Madrid, Spain, 1959, 1-36. [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]

Holdiness, 1983
Holdiness, M.R., Heats of atomization and resonance energy of some ortho-substituted benzoic acids, Thermochim. Acta, 1983, 71, 257-263. [all data]

Auwers and Roth, 1910
Auwers, K.; Roth, W.A., Thermochemische Untersuchungen. I. Uber Beziehungen zwischen Konstitution und Verbrennungswarme ungesattigter Verbindungen, Justus Liebigs Ann. Chem., 1910, 239-248. [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]

Domanska and Hofman, 1985
Domanska, U.; Hofman, T., Correlations for the solubility of normal alkanoic acids and o-tolui acid in binary solvent mixtures, J. Solution Chem., 1985, 14, 531-47. [all data]

Doering and Bragole, 1966
Doering, W. vonE.; Bragole, R.A., The Carbon Analogue of the Clasien Rearrangement of Phenyl Allyl Ether. Equilibrium of Butenylbenzenes and ortho-Propenyltoluenes, Tetrahedron, 1966, 27, 385. [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]

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, Ertl, et al., 1993
Decouzon, M.; Ertl, P.; Exner, O.; Gal, J.F.; Maria, P.C., Concepts of Sterically Hindered Resonance and Buttressing Effect - Gas-Phase Acidities of Methyl-Substituted Benzoic Acids and Basicities of, J. Am. Chem. Soc., 1993, 115, 25, 12071, https://doi.org/10.1021/ja00078a052 . [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]

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, IR Spectrum, Mass spectrum (electron ionization), References