Heptane, 2-methyl-
- Formula: C8H18
- Molecular weight: 114.2285
- IUPAC Standard InChI: InChI=1S/C8H18/c1-4-5-6-7-8(2)3/h8H,4-7H2,1-3H3
- IUPAC Standard InChIKey: JVSWJIKNEAIKJW-UHFFFAOYSA-N
- CAS Registry Number: 592-27-8
- 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. - Isotopologues:
- Other names: 2-Methylheptane; (CH3)2CH(CH2)4CH3; Methylheptane
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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
GT - Glushko Thermocenter, Russian Academy of Sciences, Moscow
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔfH°gas | -51.50 ± 0.31 | kcal/mol | Ccb | Prosen and Rossini, 1945 | ALS |
| Quantity | Value | Units | Method | Reference | Comment |
| S°gas | 109.82 ± 0.21 | cal/mol*K | N/A | Messerly J.F., 1971 | GT |
Constant pressure heat capacity of gas
| Cp,gas (cal/mol*K) | Temperature (K) | Reference | Comment |
|---|---|---|---|
| 44.486 | 298.15 | Colgate S.O., 1990 | GT |
| 48.296 | 323.15 | ||
| 54.986 | 373.15 | ||
| 59.362 | 408.15 | ||
| 63.461 | 448.15 |
Constant pressure heat capacity of gas
| Cp,gas (cal/mol*K) | Temperature (K) | Reference | Comment |
|---|---|---|---|
| 32.421 | 200. | Scott D.W., 1974 | Recommended values were obtained from the consistent correlation scheme for alkanes [ Scott D.W., 1974, 2, Scott D.W., 1974]. This approach gives a good agreement with experimental data available for alkanes. However, large uncertainties could be expected at high temperatures.; GT |
| 41.561 | 273.15 | ||
| 44.75 ± 0.05 | 298.15 | ||
| 44.981 | 300. | ||
| 57.660 | 400. | ||
| 69.020 | 500. | ||
| 78.700 | 600. | ||
| 86.800 | 700. | ||
| 93.599 | 800. | ||
| 99.500 | 900. | ||
| 104.40 | 1000. | ||
| 108.70 | 1100. | ||
| 112.50 | 1200. | ||
| 116.00 | 1300. | ||
| 119.00 | 1400. | ||
| 122.00 | 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.
Prosen and Rossini, 1945
Prosen, E.J.; Rossini, F.D.,
Heats of combustion and formation of the paraffin hydrocarbons at 25° C,
J. Res. NBS, 1945, 263-267. [all data]
Messerly J.F., 1971
Messerly J.F.,
Low-temperature thermal properties of 2-methylheptane and 2-methyldecane: the thermodynamic properties of 2-methylalkanes,
J. Chem. Thermodyn., 1971, 3, 675-687. [all data]
Colgate S.O., 1990
Colgate S.O.,
Acoustical determination of ideal gas heat capacities of three C-8 compounds,
Fluid Phase Equilib., 1990, 60, 191-203. [all data]
Scott D.W., 1974
Scott D.W.,
Chemical Thermodynamic Properties of Hydrocarbons and Related Substances. Properties of the Alkane Hydrocarbons, C1 through C10 in the Ideal Gas State from 0 to 1500 K. U.S. Bureau of Mines, Bulletin 666, 1974. [all data]
Scott D.W., 1974, 2
Scott D.W.,
Correlation of the chemical thermodynamic properties of alkane hydrocarbons,
J. Chem. Phys., 1974, 60, 3144-3165. [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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