Benzene, 1,2,3-trimethyl-
- Formula: C9H12
- Molecular weight: 120.1916
- IUPAC Standard InChI: InChI=1S/C9H12/c1-7-5-4-6-8(2)9(7)3/h4-6H,1-3H3
- 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, 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. |
References
Go To: Top, Gas phase thermochemistry 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]
Notes
Go To: Top, Gas phase thermochemistry data, References
- Symbols used in this document:
Cp,gas Constant pressure heat capacity of gas S°gas Entropy of gas at standard conditions ΔfH°gas Enthalpy of formation of gas at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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