Benzoic acid, 2-methyl-

• Formula: C₈H₈O₂
• Molecular weight: 136.1479
• IUPAC Standard InChI: InChI=1S/C8H8O2/c1-6-4-2-3-5-7(6)8(9)10/h2-5H,1H3,(H,9,10) Copy

  
• IUPAC Standard InChIKey: ZWLPBLYKEWSWPD-UHFFFAOYSA-N Copy
• CAS Registry Number: 118-90-1
• 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: o-Toluic acid; o-Methylbenzoic acid; o-Toluylic acid; 2-Methylbenzoic acid; Orthotoluic acid
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • 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
• Other data available:
  • UV/Visible spectrum
• Options:
  • Switch to SI units

Data at NIST subscription sites:

• NIST / TRC Web Thermo Tables, professional edition (thermophysical and thermochemical data)

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), 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
DRB - Donald R. Burgess, Jr.

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), 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

Constant pressure heat capacity of solid

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), 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:
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

Enthalpy of fusion

Entropy of fusion

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), 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

C₈H₇O₂^- +  =

By formula: C₈H₇O₂^- + H⁺ = C₈H₈O₂

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), 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
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi

View reactions leading to C₈H₈O₂⁺ (ion structure unspecified)

Ionization energy determinations

De-protonation reactions

C₈H₇O₂^- +  =

By formula: C₈H₇O₂^- + H⁺ = C₈H₈O₂

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), 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

Gas Phase Spectrum

Notice: This spectrum may be better viewed with a Javascript and HTML 5 enabled browser.

For Zoom

1.) Enter the desired X axis range (e.g., 100, 200)

2.) Check here for automatic Y scaling

3.) Press here to zoom

Notice: Concentration information is not available for this spectrum and, therefore, molar absorptivity values cannot be derived.

Additional Data

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

Notice: This spectrum may be better viewed with a Javascript and HTML 5 enabled browser.

For Zoom

1.) Enter the desired X axis range (e.g., 100, 200)

2.) Check here for automatic Y scaling

3.) Press here to zoom

Additional Data

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

• Symbols used in this document:
  

  Cp,solid	Constant pressure heat capacity of solid
  Tboil	Boiling point
  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 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.