Pentane, 2-methyl-
- Formula: C6H14
- Molecular weight: 86.1754
- IUPAC Standard InChI: InChI=1S/C6H14/c1-4-5-6(2)3/h6H,4-5H2,1-3H3
- IUPAC Standard InChIKey: AFABGHUZZDYHJO-UHFFFAOYSA-N
- CAS Registry Number: 107-83-5
- 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: Isohexane; 2-Methylpentane; (CH3)2CH(CH2)2CH3; Methyl pentane; UN 1208; UN 2462; Esano isomeri
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Gas phase thermochemistry data
Go To: Top, Condensed phase thermochemistry data, Reaction thermochemistry data, 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 | -174.3 ± 1.0 | kJ/mol | Ccb | Prosen and Rossini, 1945 | ALS |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔcH°gas | -4157.7 ± 0.96 | kJ/mol | Ccb | Prosen and Rossini, 1945 | Corresponding ΔfHºgas = -204.2 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS |
Constant pressure heat capacity of gas
| Cp,gas (J/mol*K) | Temperature (K) | Reference | Comment |
|---|---|---|---|
| 101.34 | 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 better agreement with experimental data than the statistical thermodynamics calculation [ Pitzer K.S., 1946] (see also [ Waddington G., 1949]).; GT |
| 131.88 | 273.15 | ||
| 142.2 ± 0.2 | 298.15 | ||
| 143.01 | 300. | ||
| 183.51 | 400. | ||
| 219.83 | 500. | ||
| 251.04 | 600. | ||
| 277.40 | 700. | ||
| 300.41 | 800. | ||
| 320.08 | 900. | ||
| 337.23 | 1000. | ||
| 351.87 | 1100. | ||
| 364.84 | 1200. | ||
| 376.56 | 1300. | ||
| 389.11 | 1400. | ||
| 397.48 | 1500. |
Constant pressure heat capacity of gas
| Cp,gas (J/mol*K) | Temperature (K) | Reference | Comment |
|---|---|---|---|
| 153.85 | 325.10 | Waddington G., 1949 | GT |
| 168.62 | 362.15 | ||
| 184.43 | 402.25 | ||
| 197.23 | 436.20 | ||
| 209.87 | 471.15 |
Condensed phase thermochemistry data
Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, 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 | -204.3 ± 1.0 | kJ/mol | Ccb | Prosen and Rossini, 1945 | ALS |
| Quantity | Value | Units | Method | Reference | Comment |
| S°liquid | 290.58 | J/mol*K | N/A | Douslin and Huffman, 1946 | DH |
| S°liquid | 292.5 | J/mol*K | N/A | Stull, 1937 | Extrapolation below 90 K, 103.72 J/mol*K.; DH |
Constant pressure heat capacity of liquid
| Cp,liquid (J/mol*K) | Temperature (K) | Reference | Comment |
|---|---|---|---|
| 194.19 | 298.15 | Ohnishi, Fujihara, et al., 1989 | DH |
| 193.96 | 298.15 | Benson and D'Arcy, 1986 | DH |
| 193.92 | 298.15 | Benson, D'Arcy, et al., 1984 | DH |
| 193.84 | 298.15 | Aicart, Kumaran, et al., 1983 | DH |
| 193.84 | 298.15 | Benson, D'Arcy, et al., 1983 | DH |
| 193.7 | 298.15 | Douslin and Huffman, 1946 | T = 13 to 300 K.; DH |
| 198.45 | 298.1 | Stull, 1937 | T = 90 to 320 K.; DH |
Reaction thermochemistry data
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, References, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Data compiled by: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. A general reaction search form is also available. Future versions of this site may rely on reaction search pages in place of the enumerated reaction displays seen below.
Individual Reactions
+
=
By formula: H2 + C6H12 = C6H14
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | -116.3 ± 0.43 | kJ/mol | Chyd | Rogers, Crooks, et al., 1987 | liquid phase |
| ΔrH° | -115.6 ± 2.2 | kJ/mol | Chyd | Molnar, Rachford, et al., 1984 | liquid phase; solvent: Dioxane |
+
=
By formula: H2 + C6H12 = C6H14
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | -116.9 ± 0.38 | kJ/mol | Chyd | Rogers, Crooks, et al., 1987 | liquid phase |
| ΔrH° | -114. | kJ/mol | Chyd | Turner, Nettleton, et al., 1958 | liquid phase; solvent: Acetic acid |
+
=
By formula: H2 + C6H12 = C6H14
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | -114.2 ± 0.57 | kJ/mol | Chyd | Rogers, Crooks, et al., 1987 | liquid phase |
| ΔrH° | -110. | kJ/mol | Chyd | Turner, Nettleton, et al., 1958 | liquid phase; solvent: Acetic acid |
2 +
=
By formula: 2H2 + C6H10 = C6H14
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | -270. ± 0.4 | kJ/mol | Chyd | Roth, Kirmse, et al., 1982 | liquid phase; solvent: Isooctane |
=
By formula: C6H14 = C6H14
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | -5.44 ± 0.88 | kJ/mol | Ciso | Prosen and Rossini, 1941 | liquid phase; Calculated from ΔHc |
+
=
By formula: H2 + C6H12 = C6H14
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | -126.7 ± 0.43 | kJ/mol | Chyd | Rogers, Crooks, et al., 1987 | liquid phase |
+
=
By formula: H2 + C6H12 = C6H14
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | -111.6 ± 0.74 | kJ/mol | Chyd | Rogers, Crooks, et al., 1987 | liquid phase |
=
By formula: C6H14 = C6H14
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 0.92 ± 0.46 | kJ/mol | Eqk | Roganov, Kabo, et al., 1972 | gas phase; At 368 K |
References
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Reaction 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]
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., 1946
Pitzer K.S.,
The entropies and related properties of branched paraffin hydrocarbons,
Chem. Rev., 1946, 39, 435-447. [all data]
Waddington G., 1949
Waddington G.,
Experimental vapor heat capacities and heats of vaporization of 2-methylpentane, 3-methylpentane, and 2,3-dimethylbutane,
J. Am. Chem. Soc., 1949, 71, 3902-3906. [all data]
Douslin and Huffman, 1946
Douslin, D.R.; Huffman, H.M.,
Low-temperature thermal data on the five isometric hexanes,
J. Am. Chem. Soc., 1946, 68, 1704-1708. [all data]
Stull, 1937
Stull, D.R.,
A semi-micro calorimeter for measuring heat capacities at low temperatures,
J. Am. Chem. Soc., 1937, 59, 2726-2733. [all data]
Ohnishi, Fujihara, et al., 1989
Ohnishi, K.; Fujihara, I.; Murakami, S.,
Thermodynamic properties of decalins mixed with hexane isomers at 298.15K. 1. Excess enthalpies and excess isobaric heat capacities,
Fluid Phase Equilib., 1989, 46, 59-72. [all data]
Benson and D'Arcy, 1986
Benson, G.C.; D'Arcy, P.J.,
Heat capacities of binary mixtures of n-octane with each of the hexane isomers at 298.15 K,
Can. J. Chem., 1986, 64, 2139-2141. [all data]
Benson, D'Arcy, et al., 1984
Benson, G.C.; D'Arcy, P.J.; Kumaran, M.K.,
Heat capacities of binary mixtures of n-heptane with hexane isomers,
Thermochim. Acta, 1984, 75, 353-360. [all data]
Aicart, Kumaran, et al., 1983
Aicart, E.; Kumaran, M.K.; Halpin, C.J.; Benson, G.C.,
Ultrasonic speeds and isentropic compressibilities of 2-methylpentan-1-ol with hexane isomers at 298.15 K,
J. Chem. Thermodynam., 1983, 15, 1189-1197. [all data]
Benson, D'Arcy, et al., 1983
Benson, G.C.; D'Arcy, P.J.; Sugamori, M.E.,
Heat capacities of binary mixtures of 1-hexanol with hexane isomers at 298.15 K,
Thermochim. Acta, 1983, 71, 161-166. [all data]
Rogers, Crooks, et al., 1987
Rogers, D.W.; Crooks, E.; Dejroongruang, K.,
Enthalpies of hydrogenation of the hexenes,
J. Chem. Thermodyn., 1987, 19, 1209-1215. [all data]
Molnar, Rachford, et al., 1984
Molnar, A.; Rachford, R.; Smith, G.V.; Liu, R.,
Heats of hydrogenation by a simple and rapid flow calorimetric method,
Appl. Catal., 1984, 9, 219-223. [all data]
Turner, Nettleton, et al., 1958
Turner, R.B.; Nettleton, J.E.; Perelman,
Heats of Hydrogenation. VI. Heats of hydrogenation of some substituted ethylenes,
J. Am. Chem. Soc., 1958, 80, 1430-1433. [all data]
Roth, Kirmse, et al., 1982
Roth, W.R.; Kirmse, W.; Hoffmann, W.; Lennartz, H.W.,
Heats of hydrogenation. III. Effect of fluoro substituents on the thermal rearrangement of cyclopropane systems,
Chem. Ber., 1982, 115, 2508-2515. [all data]
Prosen and Rossini, 1941
Prosen, E.J.R.; Rossini, F.D.,
Heats of isomerization of the five hexanes,
J. Res. NBS, 1941, 27, 289-310. [all data]
Roganov, Kabo, et al., 1972
Roganov, G.N.; Kabo, G.Ya.; Andreevskii, D.N.,
Thermodynamics of the isomerization of methylpentanes and methylheptanes,
Neftekhimiya, 1972, 12, 495-500. [all data]
Notes
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Reaction thermochemistry data, References
- Symbols used in this document:
Cp,gas Constant pressure heat capacity of gas Cp,liquid Constant pressure heat capacity of liquid S°liquid Entropy of liquid at standard conditions ΔcH°gas Enthalpy of combustion of gas at standard conditions ΔfH°gas Enthalpy of formation of gas at standard conditions ΔfH°liquid Enthalpy of formation of liquid at standard conditions ΔrH° Enthalpy of reaction at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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