Pentane, 2,2,4-trimethyl-
- Formula: C8H18
- Molecular weight: 114.2285
- 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
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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Condensed 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
DH - Eugene S. Domalski and Elizabeth D. Hearing
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔfH°liquid | -259.3 ± 1.3 | kJ/mol | Ccb | Prosen and Rossini, 1945 | ALS |
Quantity | Value | Units | Method | Reference | Comment |
ΔcH°liquid | -5461.3 ± 1.3 | kJ/mol | Ccb | Prosen and Rossini, 1945 | Corresponding ΔfHºliquid = -259.2 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS |
Quantity | Value | Units | Method | Reference | Comment |
S°liquid | 328.03 | J/mol*K | N/A | Pitzer K.S., 1940 | DH |
S°liquid | 314.6 | J/mol*K | N/A | Parks, Huffman, et al., 1930 | Extrapolation below 90 K, 66.53 J/mol*K.; DH |
Constant pressure heat capacity of liquid
Cp,liquid (J/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
242.49 | 298.15 | Costas, Huu, et al., 1988 | DH |
242.49 | 298.15 | Perez-Casas, Aicart, et al., 1988 | DH |
239.71 | 298.15 | Shiohama, Ogawa, et al., 1988 | DH |
237.85 | 293.15 | Kalali, Kohler, et al., 1987 | T = 293.15, 313.15 K.; DH |
238.871 | 298.15 | Fortier and Benson, 1976 | Average of three values.; DH |
237.8 | 298.15 | Rajagopal and Subrahmanyam, 1974 | T = 298.15 to 323.15 K.; DH |
237.8 | 298.15 | Subrahmanyam and Rajagopal, 1973 | T = 298 to 323 K.; DH |
233.7 | 300. | Auerbach, Sage, et al., 1950 | T = 300 to 366 K. Cp given as 0.4980 Btu/lb*R at 80 F.; DH |
238.57 | 298.15 | Osborne and Ginnings, 1947 | T = 283 to 318 K.; DH |
241.00 | 301.9 | Pitzer K.S., 1940 | T = 15 to 318 K. Value is unsmoothed experimental datum.; DH |
233.9 | 295.2 | Parks, Huffman, et al., 1930 | T = 88 to 295 K. Value is unsmoothed experimental datum.; DH |
References
Go To: Top, Condensed 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]
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]
Notes
Go To: Top, Condensed phase thermochemistry data, References
- Symbols used in this document:
Cp,liquid Constant pressure heat capacity of liquid S°liquid Entropy of liquid at standard conditions ΔcH°liquid Enthalpy of combustion of liquid 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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