Benzoic acid, 2,5-dimethyl-

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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-351.1 ± 1.7kJ/molCcbColomina, Jimenez, et al., 1984see Colomina, Perez-Ossorio, et al., 1961 and Colomina, Perez Ossorio, et al., 1959; ALS
Δfgas-351.1kJ/molN/ACorral, 1960Value computed using ΔfHsolid° value of -456.1±1.0 kj/mol from Corral, 1960 and ΔsubH° value of 105.0 kj/mol from Colomina, Jimenez, et al., 1984.; 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-456.1 ± 1.6kJ/molCcbColomina, Jimenez, et al., 1984see Colomina, Perez-Ossorio, et al., 1961 and Colomina, Perez Ossorio, et al., 1959; ALS
Δfsolid-456.14 ± 0.96kJ/molCcbCorral, 1960Different experiments; ALS
Quantity Value Units Method Reference Comment
Δcsolid-4514.66 ± 0.79kJ/molCcbCorral, 1960Different experiments; Corresponding Δfsolid = -456.10 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
202.7299.65Colomina, Jimenez, et al., 1984DH

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
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DRB - Donald R. Burgess, Jr.
AC - William E. Acree, Jr., James S. Chickos

Quantity Value Units Method Reference Comment
Tboil541.2KN/AAldrich Chemical Company Inc., 1990BS
Quantity Value Units Method Reference Comment
Tfus405.KN/ABirch, Dean, et al., 1949Uncertainty assigned by TRC = 3. K; TRC
Quantity Value Units Method Reference Comment
Δsub105.0 ± 0.6kJ/molVColomina, Jimenez, et al., 1984see Colomina, Perez-Ossorio, et al., 1961 and Colomina, Perez Ossorio, et al., 1959; ALS
Δsub105.0kJ/molN/AColomina, Jimenez, et al., 1984DRB
Δsub105.0 ± 0.6kJ/molMEColomina, Jimenez, et al., 1984Based on data from 315. to 334. K.; AC

Enthalpy of sublimation

ΔsubH (kJ/mol) Temperature (K) Method Reference Comment
103.6 ± 0.6324.MEColomina, Jimenez, et al., 1984Based on data from 315. to 334. K.; AC

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

C9H9O2- + Hydrogen cation = Benzoic acid, 2,5-dimethyl-

By formula: C9H9O2- + H+ = C9H10O2

Quantity Value Units Method Reference Comment
Δr1420. ± 8.8kJ/molG+TSDecouzon, Ertl, et al., 1993gas phase; relative to benzoate at 333.0 kcal/mol
Quantity Value Units Method Reference Comment
Δr1391. ± 8.4kJ/molIMREDecouzon, Ertl, et al., 1993gas phase; relative to benzoate at 333.0 kcal/mol

Gas phase ion energetics data

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

De-protonation reactions

C9H9O2- + Hydrogen cation = Benzoic acid, 2,5-dimethyl-

By formula: C9H9O2- + H+ = C9H10O2

Quantity Value Units Method Reference Comment
Δr1420. ± 8.8kJ/molG+TSDecouzon, Ertl, et al., 1993gas phase; relative to benzoate at 333.0 kcal/mol
Quantity Value Units Method Reference Comment
Δr1391. ± 8.4kJ/molIMREDecouzon, Ertl, et al., 1993gas phase; relative to benzoate at 333.0 kcal/mol

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., 1984
Colomina, M.; Jimenez, P.; Roux, M.V.; Turrion, C., Thermochemical properties of benzoic acid derivatives. XI. Vapour pressures and enthalpies of sublimation and formation of the six dimethylbenzoic acids, J. Chem. Thermodyn., 1984, 16, 1121-1127. [all data]

Colomina, Perez-Ossorio, et al., 1961
Colomina, M.; Perez-Ossorio, R.; Boned, M.L.; Panea, M.; Turrion, C., Investigaciones termoquimicas sobre los acidos alquilbenzoicos. II. Acidos dimetrilbenzoicos, Anal. Fisc. Quim. B, 1961, 57, 665-672. [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]

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

Birch, Dean, et al., 1949
Birch, S.F.; Dean, R.A.; Fidler, F.A.; Lowry, R.A., The preparation of the c(10) monocyclic aromatic hydrocarbons, J. Am. Chem. Soc., 1949, 71, 1362. [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]


Notes

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