Benzene, 1,2,3-trimethyl-

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Gas phase thermochemistry data

Go To: Top, Condensed phase thermochemistry data, Phase change 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 as indicated in comments:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
GT - Glushko Thermocenter, Russian Academy of Sciences, Moscow

Quantity Value Units Method Reference Comment
Δfgas-9.6 ± 1.3kJ/molCcbJohnson, Prosen, et al., 1945Hf by Prosen, Johnson, et al., 1946; ALS
Quantity Value Units Method Reference Comment
gas384.84 ± 0.63J/mol*KN/ATaylor R.D., 1955GT

Constant pressure heat capacity of gas

Cp,gas (J/mol*K) Temperature (K) Reference Comment
117.9200.Draeger, 1985Discrepancies with other statistically calculated values [ Taylor W.J., 1946, Hastings S.H., 1957, Thermodynamics Research Center, 1997] amount up to 5 J/mol*K in S(T) and Cp(T).; GT
148.3273.15
159.1 ± 0.4298.15
159.9300.
202.6400.
241.5500.
274.7600.
302.8700.
326.7800.
347.0900.
364.31000.
379.21100.
392.01200.
402.91300.
412.41400.
420.61500.

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
Δfliquid-58.6 ± 1.3kJ/molCcbJohnson, Prosen, et al., 1945Hf by Prosen, Johnson, et al., 1946; ALS
Quantity Value Units Method Reference Comment
Δcliquid-5198.0 ± 1.2kJ/molCcbJohnson, Prosen, et al., 1945Hf by Prosen, Johnson, et al., 1946; Corresponding Δfliquid = -58.53 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS
Quantity Value Units Method Reference Comment
liquid267.94J/mol*KN/ATaylor, Johnson, et al., 1955DH

Constant pressure heat capacity of liquid

Cp,liquid (J/mol*K) Temperature (K) Reference Comment
216.44298.15Taylor, Johnson, et al., 1955T = 19 to 301 K.; 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.
CAL - James S. Chickos, William E. Acree, Jr., Joel F. Liebman, Students of Chem 202 (Introduction to the Literature of Chemistry), University of Missouri -- St. Louis
DH - Eugene S. Domalski and Elizabeth D. Hearing

Quantity Value Units Method Reference Comment
Tboil449.2 ± 0.2KAVGN/AAverage of 24 out of 29 values; Individual data points
Quantity Value Units Method Reference Comment
Tfus247.7 ± 0.2KAVGN/AAverage of 13 values; Individual data points
Quantity Value Units Method Reference Comment
Ttriple247.81KN/ATaylor, Johnson, et al., 1955, 2Crystal phase 1 phase; Uncertainty assigned by TRC = 0.05 K; TRC
Ttriple247.800KN/AKilpatrick, 1953Uncertainty assigned by TRC = 0.05 K; TRC
Quantity Value Units Method Reference Comment
Tc664.5 ± 0.5KN/ATsonopoulos and Ambrose, 1995 
Tc665.50KN/AKay and Pak, 1980Uncertainty assigned by TRC = 1.5 K; TRC
Tc664.39KN/AAmbrose, Broderick, et al., 1967Uncertainty assigned by TRC = 0.1 K; TRC
Tc664.5KN/AAmbrose, Cox, et al., 1960Uncertainty assigned by TRC = 0.3 K; Visual, PRT, IPTS-48; TRC
Quantity Value Units Method Reference Comment
Pc34.5 ± 0.4barN/ATsonopoulos and Ambrose, 1995 
Pc34.426barN/AKay and Pak, 1980Uncertainty assigned by TRC = 0.50 bar; TRC
Pc34.54barN/AAmbrose, Broderick, et al., 1967Uncertainty assigned by TRC = 0.06 bar; TRC
Quantity Value Units Method Reference Comment
Δvap49.0 ± 0.2kJ/molAVGN/AAverage of 7 values; Individual data points

Enthalpy of vaporization

ΔvapH (kJ/mol) Temperature (K) Method Reference Comment
44.8378.AStephenson and Malanowski, 1987Based on data from 363. to 456. K. See also Forziati, Norris, et al., 1949.; AC
42.5265.RGHopke and Sears, 1948Based on data from 259. to 270. K.; AC

Antoine Equation Parameters

log10(P) = A − (B / (T + C))
    P = vapor pressure (bar)
    T = temperature (K)

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Temperature (K) A B C Reference
363.48 to 450.284.165721593.958-66.072Forziati, Norris, et al., 1949, 2

Enthalpy of fusion

ΔfusH (kJ/mol) Temperature (K) Reference Comment
8.18247.8Domalski and Hearing, 1996AC

Entropy of fusion

ΔfusS (J/mol*K) Temperature (K) Reference Comment
3.218.7Domalski and Hearing, 1996CAL
5.8230.3
33.01247.8

Enthalpy of phase transition

ΔHtrs (kJ/mol) Temperature (K) Initial Phase Final Phase Reference Comment
0.6586218.70crystaline, IIIcrystaline, IITaylor, Johnson, et al., 1955DH
1.3360230.27crystaline, IIcrystaline, ITaylor, Johnson, et al., 1955DH
8.1801247.81crystaline, IliquidTaylor, Johnson, et al., 1955DH

Entropy of phase transition

ΔStrs (J/mol*K) Temperature (K) Initial Phase Final Phase Reference Comment
3.01218.70crystaline, IIIcrystaline, IITaylor, Johnson, et al., 1955DH
5.80230.27crystaline, IIcrystaline, ITaylor, Johnson, et al., 1955DH
33.01247.81crystaline, IliquidTaylor, Johnson, et al., 1955DH

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:


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:
L - Sharon G. Lias

Data compiled as indicated in comments:
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

View reactions leading to C9H12+ (ion structure unspecified)

Quantity Value Units Method Reference Comment
IE (evaluated)8.42 ± 0.02eVN/AN/AL

Ionization energy determinations

IE (eV) Method Reference Comment
8.42 ± 0.02EQLias and Ausloos, 1978LLK
8.48 ± 0.01PIPrice, Bralsford, et al., 1959RDSH
8.42PEHowell, Goncalves, et al., 1984Vertical value; LBLHLM
8.6 ± 0.03PEKlessinger, 1972Vertical value; LLK

Mass spectrum (electron ionization)

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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

Spectrum

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Mass spectrum
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Additional Data

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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, 1992
NIST MS number 125395

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References

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

Johnson, Prosen, et al., 1945
Johnson, W.H.; Prosen, E.J.; Rossini, F.D., Heats of combustion and isomerization of the eight C9H12 alkylbenzenes, J. Res. NBS, 1945, 35, 141-146. [all data]

Prosen, Johnson, et al., 1946
Prosen, E.J.; Johnson, W.H.; Rossini, F.D., Heats of combustion and formation at 25°C of the alkylbenzenes through C10H14, and of the higher normal monoalkylbenzenes, J. Res. NBS, 1946, 36, 455-461. [all data]

Taylor R.D., 1955
Taylor R.D., Entropy, heat capacity, and heats of transition of 1,2,3-trimethylbenzene, J. Chem. Phys., 1955, 23, 1225-1231. [all data]

Draeger, 1985
Draeger, J.A., The methylbenzenes II. Fundamental vibrational shifts, statistical thermodynamic functions, and properties of formation, J. Chem. Thermodyn., 1985, 17, 263-275. [all data]

Taylor W.J., 1946
Taylor W.J., Heats, equilibrium constants, and free energies of formation of the alkylbenzenes, J. Res. Nat. Bur. Stand., 1946, 37, 95-122. [all data]

Hastings S.H., 1957
Hastings S.H., Thermodynamic properties of selected methylbenzenes from 0 to 1000 K, J. Phys. Chem., 1957, 61, 730-735. [all data]

Thermodynamics Research Center, 1997
Thermodynamics Research Center, Selected Values of Properties of Chemical Compounds., Thermodynamics Research Center, Texas A&M University, College Station, Texas, 1997. [all data]

Taylor, Johnson, et al., 1955
Taylor, R.D.; Johnson, B.H.; Kilpatrick, J.E., Entropy, heat capacity, and heats of transition of 1,2,3-trimethylbenzene, J. Chem. Phys., 1955, 23, 1225-1231. [all data]

Taylor, Johnson, et al., 1955, 2
Taylor, R.D.; Johnson, B.H.; Kilpatrick, J.E., Entropy, Heat Capacity and Heats of Trans. of 1,2,3-Trimethylbenzene, J. Chem. Phys., 1955, 23, 1225. [all data]

Kilpatrick, 1953
Kilpatrick, J.E., Unpublished, 1953. [all data]

Tsonopoulos and Ambrose, 1995
Tsonopoulos, C.; Ambrose, D., Vapor-Liquid Critical Properties of Elements and Compounds. 3. Aromatic Hydrocarbons, J. Chem. Eng. Data, 1995, 40, 547-558. [all data]

Kay and Pak, 1980
Kay, W.B.; Pak, S.C., Determination of the critical constants of high-boiling hydrocarbons. Experiments with gallium as a containing fluid, J. Chem. Thermodyn., 1980, 12, 673. [all data]

Ambrose, Broderick, et al., 1967
Ambrose, D.; Broderick, B.E.; Townsend, R., The Vapour Pressures above the Normal Boiling Point and the Critical Pressures of Some Aromatic Hydrocarbons, J. Chem. Soc. , 1967, 1967, 1967, 633-41. [all data]

Ambrose, Cox, et al., 1960
Ambrose, D.; Cox, J.D.; Townsend, R., The critical temperatures of forty organic compounds, Trans. Faraday Soc., 1960, 56, 1452. [all data]

Stephenson and Malanowski, 1987
Stephenson, Richard M.; Malanowski, Stanislaw, Handbook of the Thermodynamics of Organic Compounds, 1987, https://doi.org/10.1007/978-94-009-3173-2 . [all data]

Forziati, Norris, et al., 1949
Forziati, Alphonse F.; Norris, William R.; Rossini, Frederick D., Vapor pressures and boiling points of sixty API-NBS hydrocarbons, J. RES. NATL. BUR. STAN., 1949, 43, 6, 555-17, https://doi.org/10.6028/jres.043.050 . [all data]

Hopke and Sears, 1948
Hopke, E.R.; Sears, G.W., Vapor Pressures of Trimethylbenzenes in the Low Pressure Region 1,2, J. Am. Chem. Soc., 1948, 70, 11, 3801-3803, https://doi.org/10.1021/ja01191a077 . [all data]

Forziati, Norris, et al., 1949, 2
Forziati, A.F.; Norris, W.R.; Rossini, F.D., Vapor Pressures and Boiling Points of Sixty API-NBS Hydrocarbons, J. Res. Natl. Bur. Stand. (U.S.), 1949, 43, 6, 555-563, https://doi.org/10.6028/jres.043.050 . [all data]

Domalski and Hearing, 1996
Domalski, Eugene S.; Hearing, Elizabeth D., Heat Capacities and Entropies of Organic Compounds in the Condensed Phase. Volume III, J. Phys. Chem. Ref. Data, 1996, 25, 1, 1, https://doi.org/10.1063/1.555985 . [all data]

Lias and Ausloos, 1978
Lias, S.G.; Ausloos, P.J., eIonization energies of organic compounds by equilibrium measurements, J. Am. Chem. Soc., 1978, 100, 6027. [all data]

Price, Bralsford, et al., 1959
Price, W.C.; Bralsford, R.; Harris, P.V.; Ridley, R.G., Ultra-violet spectra and ionization potentials of hydrocarbon molecules, Spectrochim. Acta, 1959, 14, 45. [all data]

Howell, Goncalves, et al., 1984
Howell, J.O.; Goncalves, J.M.; Amatore, C.; Klasinc, L.; Wightman, R.M.; Kochi, J.K., Electron transfer from aromatic hydrocarbons and their π-complexes with metals. Comparison of the standard oxidation potentials and vertical ionization potentials, J. Am. Chem. Soc., 1984, 106, 3968. [all data]

Klessinger, 1972
Klessinger, M., Ionization potentials of substituted benzenes, Angew. Chem. Int. Ed. Engl., 1972, 11, 525. [all data]


Notes

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Gas phase ion energetics data, Mass spectrum (electron ionization), References