Pentane, 2,2,4-trimethyl-

• Formula: C₈H₁₈
• Molecular weight: 114.2285
• IUPAC Standard InChI: InChI=1S/C8H18/c1-7(2)6-8(3,4)5/h7H,6H2,1-5H3 Copy

  
• IUPAC Standard InChIKey: NHTMVDHEPJAVLT-UHFFFAOYSA-N Copy
• 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
  The 3d structure may be viewed using Java or Javascript.
• Other names: Isooctane; Isobutyltrimethylmethane; 2,2,4-Trimethylpentane; (CH3)2CHCH2C(CH3)3; Isobutyltrimethylethane; UN 1262
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• Information on this page:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Phase change data
  • Reaction thermochemistry data
  • Henry's Law data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • Gas Chromatography
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
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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

Constant pressure heat capacity of gas

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

Constant pressure heat capacity of liquid

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:
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron

Ionization energy determinations

References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Gas phase ion energetics 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]

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]

Pitzer K.S., 1940
Pitzer K.S., The thermodynamics of n-heptane and 2,2,4-trimethylpentane, including heat capacities, heats of fusion and vaporization and entropies, J. Am. Chem. Soc., 1940, 62, 1224-1227. [all data]

Parks, Huffman, et al., 1930
Parks, G.S.; Huffman, H.M.; Thomas, S.B., Thermal data on organic compounds. VI. The heat capacities, entropies and free energies of some saturated, non-benzenoid hydrocarbons, J. Am. Chem. Soc., 1930, 52, 1032-1041. [all data]

Costas, Huu, et al., 1988
Costas, M.; Huu, V.T.; Patterson, D.; Caceres-Alonso, M.; Tardajos, G.; Aicart, E., Liquid structure and second-order mixing functions for l-chloronaphthalene with linear and branched alkanes, J. Chem. Soc., Faraday Trans., 1988, 1 84(5), 1603-1616. [all data]

Perez-Casas, Aicart, et al., 1988
Perez-Casas, S.; Aicart, E.; Trojo, L.M.; Costas, M., Excess heat capacity. Chlorobenzene-2,2,4,4,6,8,8-heptamethylnonane, Int. Data Ser., Sel. Data Mixtures, 1988, (2)A, 123. [all data]

Shiohama, Ogawa, et al., 1988
Shiohama, Y.; Ogawa, H.; Murakami, S.; Fujihara, I., Excess molar isobaric heat capacities and isentropic compressibilities of (cis- or trans-decalin + benzene or toluene or iso-octane or n-heptane) at 298.15 K, J. Chem. Thermodynam., 1988, 20, 1183-1189. [all data]

Kalali, Kohler, et al., 1987
Kalali, H.; Kohler, F.; Svejda, P., Excess properties of the mixture bis(2-dichlorethyl)ether (chlorex) + 2,2,4-trimethylpentane (isooctane), Monatsh. Chem., 1987, 118, 1-18. [all data]

Fortier and Benson, 1976
Fortier, J.-L.; Benson, G.C., Excess heat capacities of binary liquid mixtures determined with a Picker flow calorimeter, J. Chem. Thermodynam., 1976, 8, 411-423. [all data]

Rajagopal and Subrahmanyam, 1974
Rajagopal, E.; Subrahmanyam, S.V., Excess function of VE,(dVE/dp)T, and CpE of isooctane + benzene and + toluene, J. Chem. Thermodynam., 1974, 6, 873-876. [all data]

Subrahmanyam and Rajagopal, 1973
Subrahmanyam, S.V.; Rajagopal, E., Excess thermodynamic functions of the systems isooctane + carbon tetrachloride and isooctane + cyclohexane, Z. Phys. Chem. [NF], 1973, 85, 256-268. [all data]

Auerbach, Sage, et al., 1950
Auerbach, C.E.; Sage, B.H.; Lacey, W.N., Isobaric heat capacities at bubble point, Ind. Eng. Chem., 1950, 42, 110-113. [all data]

Osborne and Ginnings, 1947
Osborne, N.S.; Ginnings, D.C., Measurements of heat of vaporization and heat capacity of a number of hydrocarbons, J. Res. NBS, 1947, 39, 453-477. [all data]

Al-Joboury and Turner, 1964
Al-Joboury, M.I.; Turner, D.W., Molecular photoelectron spectroscopy. Part II. A summary of ionization potentials, J. Chem. Soc., 1964, 4434. [all data]

Watanabe, Nakayama, et al., 1962
Watanabe, K.; Nakayama, T.; Mottl, J., Ionization potentials of some molecules, J. Quant. Spectry. Radiative Transfer, 1962, 2, 369. [all data]

Notes

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• Symbols used in this document:
  

  Cp,gas	Constant pressure heat capacity of gas
  Cp,liquid	Constant pressure heat capacity of liquid
  IE (evaluated)	Recommended ionization energy
  S°liquid	Entropy of liquid at standard conditions
  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

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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