Pentane, 2,3-dimethyl-
- Formula: C7H16
- Molecular weight: 100.2019
- IUPAC Standard InChI: InChI=1S/C7H16/c1-5-7(4)6(2)3/h6-7H,5H2,1-4H3
- IUPAC Standard InChIKey: WGECXQBGLLYSFP-UHFFFAOYSA-N
- CAS Registry Number: 565-59-3
- 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. - Stereoisomers:
- Other names: 2,3-Dimethylpentane; 3,4-Dimethylpentane
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Gas phase thermochemistry data
Go To: Top, Condensed phase thermochemistry data, Reaction thermochemistry data, Henry's Law 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
DRB - Donald R. Burgess, Jr.
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔfH°gas | -47.62 ± 0.30 | kcal/mol | Ccb | Prosen and Rossini, 1945 | ALS |
| ΔfH°gas | -47.49 | kcal/mol | N/A | Davies and Gilbert, 1941 | Value computed using ΔfHliquid° value of -233.0±1.0 kj/mol from Davies and Gilbert, 1941 and ΔvapH° value of 34.3 kj/mol from Prosen and Rossini, 1945.; DRB |
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
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔfH°liquid | -55.81 ± 0.30 | kcal/mol | Ccb | Prosen and Rossini, 1945 | ALS |
| ΔfH°liquid | -55.7 ± 0.3 | kcal/mol | Ccb | Davies and Gilbert, 1941 | ALS |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔcH°liquid | -1149.09 ± 0.28 | kcal/mol | Ccb | Prosen and Rossini, 1945 | Corresponding ΔfHºliquid = -55.79 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS |
| ΔcH°liquid | -1149.1 ± 0.3 | kcal/mol | Ccb | Davies and Gilbert, 1941 | Corresponding ΔfHºliquid = -55.82 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS |
| Quantity | Value | Units | Method | Reference | Comment |
| S°liquid | 71.01 | cal/mol*K | N/A | Finke, Messerly, et al., 1976 | DH |
| S°liquid | 73.21 | cal/mol*K | N/A | Huffman, Parks, et al., 1930 | Extrapolation below 70 K, 69.5 J/mol*K. Forms glass at low temperatures. Value includes estimated zero point entropy of 17 J/mol*K.; DH |
Constant pressure heat capacity of liquid
| Cp,liquid (cal/mol*K) | Temperature (K) | Reference | Comment |
|---|---|---|---|
| 52.17 | 298.15 | Finke, Messerly, et al., 1976 | T = 10 to 400 K.; DH |
| 51.60 | 291.5 | Huffman, Parks, et al., 1930 | T = 68 to 292 K. Value is unsmoothed experimental datum.; DH |
Reaction 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 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: C7H14 + H2 = C7H16
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | -25.43 ± 0.38 | kcal/mol | Chyd | Rogers and Dejroongruang, 1989 | liquid phase; solvent: Cyclohexane |
| ΔrH° | -27.0 ± 1.1 | kcal/mol | Chyd | Lopes, Nunes, et al., 1975 | liquid phase; solvent: Acetic acid |
=
By formula: C7H16 = C7H16
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | -2.18 ± 0.26 | kcal/mol | Ccb | Prosen and Rossini, 1941 | liquid phase; Heat of Isomerization |
| ΔrH° | -2.80 ± 0.30 | kcal/mol | Ccb | Prosen and Rossini, 1941 | gas phase; Heat of Isomerization |
+
=
By formula: H2 + C7H14 = C7H16
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | -27.25 ± 0.31 | kcal/mol | Chyd | Rogers and Dejroongruang, 1989 | liquid phase; solvent: Cyclohexane |
+
=
By formula: H2 + C7H14 = C7H16
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | -25.81 ± 0.1 | kcal/mol | Chyd | Rogers and Dejroongruang, 1989 | liquid phase; solvent: Cyclohexane |
+
=
By formula: H2 + C7H14 = C7H16
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | -25.88 ± 0.1 | kcal/mol | Chyd | Rogers and Dejroongruang, 1989 | liquid phase; solvent: Cyclohexane |
+
=
By formula: H2 + C7H14 = C7H16
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | -27.1 ± 0.2 | kcal/mol | Chyd | Rogers and Dejroongruang, 1989 | liquid phase; solvent: Cyclohexane |
+
=
By formula: H2 + C7H14 = C7H16
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 29.1 ± 0.2 | kcal/mol | Chyd | Rogers and Dejroongruang, 1989 | liquid phase; solvent: Cyclohexane |
Henry's Law 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 by: Rolf Sander
Henry's Law constant (water solution)
kH(T) = k°H exp(d(ln(kH))/d(1/T) ((1/T) - 1/(298.15 K)))
k°H = Henry's law constant for solubility in water at 298.15 K (mol/(kg*bar))
d(ln(kH))/d(1/T) = Temperature dependence constant (K)
| k°H (mol/(kg*bar)) | d(ln(kH))/d(1/T) (K) | Method | Reference | Comment |
|---|---|---|---|---|
| 0.00057 | Q | N/A | missing citation give several references for the Henry's law constants but don't assign them to specific species. | |
| 0.00058 | L | N/A |
References
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Reaction thermochemistry data, Henry's Law 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]
Davies and Gilbert, 1941
Davies, G.F.; Gilbert, E.C.,
Heats of combustion and formation of the nine isomeric heptanes in the liquid state,
J. Am. Chem. Soc., 1941, 63, 2730-2732. [all data]
Finke, Messerly, et al., 1976
Finke, H.L.; Messerly, J.F.; Douslin, D.R.,
Low-temperature thermal quantities for five alkyl-substituted pentanes,
J. Chem. Thermodynam., 1976, 8, 965-983. [all data]
Huffman, Parks, et al., 1930
Huffman, H.M.; Parks, G.S.; Thomas, S.B.,
Thermal data on organic compounds. VIII. The heat capacities, entropies and free energies of the isomeric heptanes,
J. Am. Chem. Soc., 1930, 52, 3241-3251. [all data]
Rogers and Dejroongruang, 1989
Rogers, D.W.; Dejroongruang, K.,
Enthalpies of hydrogenation of the dimethylpentenes, ethylpentenes, methylbutene, and trimethylbutene,
J. Chem. Thermodyn., 1989, 21, 1115-1120. [all data]
Lopes, Nunes, et al., 1975
Lopes, M.T.R.; Nunes, M.F.T.; Florencio, M.H.F.S.; Mota, M.M.G.; Fernandez, M.T.N.,
Heats of hydrogenation in solution. I. Calorimeter for semimicro determinations,
Rev. Port. Quim., 1975, 15, 129-132. [all data]
Prosen and Rossini, 1941
Prosen, E.J.R.; Rossini, F.D.,
Heats of isomerization of the nine heptanes,
J. Res. NBS, 1941, 27, 519-528. [all data]
Notes
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Reaction thermochemistry data, Henry's Law data, References
- Symbols used in this document:
Cp,liquid Constant pressure heat capacity of liquid S°liquid Entropy of liquid at standard conditions d(ln(kH))/d(1/T) Temperature dependence parameter for Henry's Law constant k°H Henry's Law constant at 298.15K 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 ΔrH° Enthalpy of reaction at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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