Benzene, 1,2,3-trimethyl-
- Formula: C9H12
- Molecular weight: 120.1916
- IUPAC Standard InChIKey: FYGHSUNMUKGBRK-UHFFFAOYSA-N
- CAS Registry Number: 526-73-8
- 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: Hemimellitene; 1,2,3-Trimethylbenzene; Hemellitol; 1,2,3-TrimethyIbenzene; 1,2,3-trimethylbenzene (hemimellitene)
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Gas phase thermochemistry data
Go To: Top, Condensed phase thermochemistry data, Phase change 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 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 |
---|---|---|---|---|---|
ΔfH°gas | -9.6 ± 1.3 | kJ/mol | Ccb | Johnson, Prosen, et al., 1945 | Hf by Prosen, Johnson, et al., 1946; ALS |
Quantity | Value | Units | Method | Reference | Comment |
S°gas | 384.84 ± 0.63 | J/mol*K | N/A | Taylor R.D., 1955 | GT |
Constant pressure heat capacity of gas
Cp,gas (J/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
117.9 | 200. | Draeger, 1985 | Discrepancies 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 |
148.3 | 273.15 | ||
159.1 ± 0.4 | 298.15 | ||
159.9 | 300. | ||
202.6 | 400. | ||
241.5 | 500. | ||
274.7 | 600. | ||
302.8 | 700. | ||
326.7 | 800. | ||
347.0 | 900. | ||
364.3 | 1000. | ||
379.2 | 1100. | ||
392.0 | 1200. | ||
402.9 | 1300. | ||
412.4 | 1400. | ||
420.6 | 1500. |
Condensed phase thermochemistry data
Go To: Top, Gas phase thermochemistry data, Phase change 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 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 |
---|---|---|---|---|---|
ΔfH°liquid | -58.6 ± 1.3 | kJ/mol | Ccb | Johnson, Prosen, et al., 1945 | Hf by Prosen, Johnson, et al., 1946; ALS |
Quantity | Value | Units | Method | Reference | Comment |
ΔcH°liquid | -5198.0 ± 1.2 | kJ/mol | Ccb | Johnson, Prosen, et al., 1945 | Hf by Prosen, Johnson, et al., 1946; Corresponding ΔfHºliquid = -58.53 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS |
Quantity | Value | Units | Method | Reference | Comment |
S°liquid | 267.94 | J/mol*K | N/A | Taylor, Johnson, et al., 1955 | DH |
Constant pressure heat capacity of liquid
Cp,liquid (J/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
216.44 | 298.15 | Taylor, Johnson, et al., 1955 | T = 19 to 301 K.; DH |
Phase change data
Go To: Top, Gas phase thermochemistry data, Condensed phase 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 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 |
---|---|---|---|---|---|
Tboil | 449.2 ± 0.2 | K | AVG | N/A | Average of 24 out of 29 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
Tfus | 247.7 ± 0.2 | K | AVG | N/A | Average of 13 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
Ttriple | 247.81 | K | N/A | Taylor, Johnson, et al., 1955, 2 | Crystal phase 1 phase; Uncertainty assigned by TRC = 0.05 K; TRC |
Ttriple | 247.800 | K | N/A | Kilpatrick, 1953 | Uncertainty assigned by TRC = 0.05 K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Tc | 664.5 ± 0.5 | K | N/A | Tsonopoulos and Ambrose, 1995 | |
Tc | 665.50 | K | N/A | Kay and Pak, 1980 | Uncertainty assigned by TRC = 1.5 K; TRC |
Tc | 664.39 | K | N/A | Ambrose, Broderick, et al., 1967 | Uncertainty assigned by TRC = 0.1 K; TRC |
Tc | 664.5 | K | N/A | Ambrose, Cox, et al., 1960 | Uncertainty assigned by TRC = 0.3 K; Visual, PRT, IPTS-48; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Pc | 34.5 ± 0.4 | bar | N/A | Tsonopoulos and Ambrose, 1995 | |
Pc | 34.426 | bar | N/A | Kay and Pak, 1980 | Uncertainty assigned by TRC = 0.50 bar; TRC |
Pc | 34.54 | bar | N/A | Ambrose, Broderick, et al., 1967 | Uncertainty assigned by TRC = 0.06 bar; TRC |
Quantity | Value | Units | Method | Reference | Comment |
ΔvapH° | 49.0 ± 0.2 | kJ/mol | AVG | N/A | Average of 7 values; Individual data points |
Enthalpy of vaporization
ΔvapH (kJ/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
44.8 | 378. | A | Stephenson and Malanowski, 1987 | Based on data from 363. to 456. K. See also Forziati, Norris, et al., 1949.; AC |
42.5 | 265. | RG | Hopke and Sears, 1948 | Based 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 450.28 | 4.16572 | 1593.958 | -66.072 | Forziati, Norris, et al., 1949, 2 |
Enthalpy of fusion
ΔfusH (kJ/mol) | Temperature (K) | Reference | Comment |
---|---|---|---|
8.18 | 247.8 | Domalski and Hearing, 1996 | AC |
Entropy of fusion
ΔfusS (J/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
3. | 218.7 | Domalski and Hearing, 1996 | CAL |
5.8 | 230.3 | ||
33.01 | 247.8 |
Enthalpy of phase transition
ΔHtrs (kJ/mol) | Temperature (K) | Initial Phase | Final Phase | Reference | Comment |
---|---|---|---|---|---|
0.6586 | 218.70 | crystaline, III | crystaline, II | Taylor, Johnson, et al., 1955 | DH |
1.3360 | 230.27 | crystaline, II | crystaline, I | Taylor, Johnson, et al., 1955 | DH |
8.1801 | 247.81 | crystaline, I | liquid | Taylor, Johnson, et al., 1955 | DH |
Entropy of phase transition
ΔStrs (J/mol*K) | Temperature (K) | Initial Phase | Final Phase | Reference | Comment |
---|---|---|---|---|---|
3.01 | 218.70 | crystaline, III | crystaline, II | Taylor, Johnson, et al., 1955 | DH |
5.80 | 230.27 | crystaline, II | crystaline, I | Taylor, Johnson, et al., 1955 | DH |
33.01 | 247.81 | crystaline, I | liquid | Taylor, Johnson, et al., 1955 | DH |
References
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, 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]
Notes
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, References
- Symbols used in this document:
Cp,gas Constant pressure heat capacity of gas Cp,liquid Constant pressure heat capacity of liquid Pc Critical pressure S°gas Entropy of gas at standard conditions S°liquid Entropy of liquid at standard conditions Tboil Boiling point Tc Critical temperature Tfus Fusion (melting) point Ttriple Triple point temperature ΔHtrs Enthalpy of phase transition ΔStrs Entropy of phase transition ΔcH°liquid Enthalpy of combustion of liquid at standard conditions ΔfH°gas Enthalpy of formation of gas at standard conditions ΔfH°liquid Enthalpy of formation of liquid at standard conditions ΔfusH Enthalpy of fusion ΔfusS Entropy of fusion ΔvapH Enthalpy of vaporization ΔvapH° Enthalpy of vaporization at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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