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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Reaction thermochemistry data
Go To: Top, Gas phase ion energetics 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: C8H18 = C8H18
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | -5.23 ± 0.92 | kJ/mol | Ciso | Prosen and Rossini, 1945 | liquid phase; Calculated from ΔHc |
+
=
By formula: H2 + C8H16 = C8H18
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | -115.1 ± 0.7 | kJ/mol | Chyd | Rogers, Dejroongruang, et al., 1992 | liquid phase; solvent: Cyclohexane |
+
=
By formula: H2 + C8H16 = C8H18
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | -126.4 ± 2.0 | kJ/mol | Chyd | Rogers, Dejroongruang, et al., 1992 | liquid phase; solvent: Cyclohexane |
=
By formula: C8H18 = C8H18
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 1.86 ± 0.42 | kJ/mol | Eqk | Roganov, Kabo, et al., 1972 | gas phase; At 1368 K |
=
By formula: C8H18 = C8H18
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 1.3 ± 0.4 | kJ/mol | Eqk | Roganov, Kabo, et al., 1972 | gas phase; At 368 K |
Gas phase ion energetics data
Go To: Top, 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 evaluated as indicated in comments:
L - Sharon G. Lias
Data compiled as indicated in comments:
LL - Sharon G. Lias and Joel F. Liebman
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| IE (evaluated) | 9.84 ± 0.10 | eV | N/A | N/A | L |
Ionization energy determinations
| IE (eV) | Method | Reference | Comment |
|---|---|---|---|
| 9.76 | EST | Luo and Pacey, 1992 | LL |
| 9.84 ± 0.10 | EVAL | Lias, 1982 | LBLHLM |
| 9.74 ± 0.15 | EQ | Mautner(Meot-Ner), Sieck, et al., 1981 | LLK |
References
Go To: Top, Reaction 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 isomerization of the 18 octanes,
J. Res. NBS, 1945, 34, 163-174. [all data]
Rogers, Dejroongruang, et al., 1992
Rogers, D.W.; Dejroongruang, K.; Samuel, S.D.; Fang, W.; Zhao, Y.,
Enthalpies of hydrogenation of the octenes and the methylheptenes,
J. Chem. Thermodyn., 1992, 24, 561-565. [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]
Luo and Pacey, 1992
Luo, Y.-R.; Pacey, P.D.,
Effects of alkyl substitution on ionization energies of alkanes and haloalkanes and on heats of formation of their molecular cations. Part 2. Alkanes and chloro-, bromo- and iodoalkanes,
Int. J. Mass Spectrom. Ion Processes, 1992, 112, 63. [all data]
Lias, 1982
Lias, S.G.,
Thermochemical information from ion-molecule rate constants,
Ion Cyclotron Reson. Spectrom. 1982, 1982, 409. [all data]
Mautner(Meot-Ner), Sieck, et al., 1981
Mautner(Meot-Ner), M.; Sieck, L.W.; Ausloos, P.,
Ionization of normal alkanes: Enthalpy, entropy, structural, and isotope effects,
J. Am. Chem. Soc., 1981, 103, 5342. [all data]
Notes
Go To: Top, Reaction thermochemistry data, Gas phase ion energetics data, References
- Symbols used in this document:
IE (evaluated) Recommended ionization energy ΔrH° Enthalpy of reaction at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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