- Formula: C8H18
- Molecular weight: 114.2285
- IUPAC Standard InChI:
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- IUPAC Standard InChIKey: NHTMVDHEPJAVLT-UHFFFAOYSA-N
- CAS Registry Number: 540-84-1
- Chemical structure:
This structure is also available as a 2d Mol file or as a computed 3d SD file
- Other names: Isooctane; Isobutyltrimethylmethane; 2,2,4-Trimethylpentane; (CH3)2CHCH2C(CH3)3; Isobutyltrimethylethane; UN 1262
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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
|fH°gas||-53.57 ± 0.32||kcal/mol||Ccb||Prosen and Rossini, 1945||ALS|
Constant pressure heat capacity of gas
|Cp,gas (cal/mol*K)||Temperature (K)||Reference||Comment|
|31.209||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|
|45.03 ± 0.1||298.15|
Go To: Top, Gas phase thermochemistry data, Notes
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]
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]
Go To: Top, Gas phase thermochemistry data, References
- Symbols used in this document:
Cp,gas Constant pressure heat capacity of gas fH°gas Enthalpy of formation of gas at standard conditions
- Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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