Isobutane
- Formula: C4H10
- Molecular weight: 58.1222
- IUPAC Standard InChIKey: NNPPMTNAJDCUHE-UHFFFAOYSA-N
- CAS Registry Number: 75-28-5
- 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: Propane, 2-methyl-; Trimethylmethane; 1,1-Dimethylethane; 2-Methylpropane; iso-C4H10; i-Butane; UN 1969; R 600a; tert-Butane; A 31; Methylpropane; A 31 (hydrocarbon)
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Reaction 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:
B - John E. Bartmess
ALS - 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
C4H9- + =
By formula: C4H9- + H+ = C4H10
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 1728. ± 8.4 | kJ/mol | Bran | DePuy, Gronert, et al., 1989 | gas phase; B |
ΔrH° | 1735. ± 20. | kJ/mol | Bran | Peerboom, Rademaker, et al., 1992 | gas phase; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 1692. ± 8.8 | kJ/mol | H-TS | DePuy, Gronert, et al., 1989 | gas phase; B |
ΔrG° | 1699. ± 21. | kJ/mol | H-TS | Peerboom, Rademaker, et al., 1992 | gas phase; B |
C4H9- + =
By formula: C4H9- + H+ = C4H10
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 1728. ± 8.4 | kJ/mol | Bran | DePuy, Gronert, et al., 1989 | gas phase; B |
ΔrH° | 1732. ± 8.4 | kJ/mol | Bran | DePuy, Bierbaum, et al., 1984 | gas phase; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 1697. ± 8.8 | kJ/mol | H-TS | DePuy, Gronert, et al., 1989 | gas phase; B |
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -117.8 ± 0.42 | kJ/mol | Chyd | Kistiakowsky, Ruhoff, et al., 1935 | gas phase; Reanalyzed by Cox and Pilcher, 1970, Original value = -118.78 ± 0.75 kJ/mol; At 355 °K; ALS |
By formula: C4H10 = C4H10
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -9.699 | kJ/mol | Eqk | Pines, Kvetinskas, et al., 1945 | gas phase; Heat of isomerization; ALS |
References
Go To: Top, Reaction thermochemistry data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
DePuy, Gronert, et al., 1989
DePuy, C.H.; Gronert, S.; Barlow, S.E.; Bierbaum, V.M.; Damrauer, R.,
The Gas Phase Acidities of the Alkanes,
J. Am. Chem. Soc., 1989, 111, 6, 1968, https://doi.org/10.1021/ja00188a003
. [all data]
Peerboom, Rademaker, et al., 1992
Peerboom, R.A.L.; Rademaker, G.J.; Dekoning, L.J.; Nibbering, N.M.M.,
Stabilization of Cycloalkyl Carbanions in the Gas Phase,
Rapid Commun. Mass Spectrom., 1992, 6, 6, 394, https://doi.org/10.1002/rcm.1290060608
. [all data]
DePuy, Bierbaum, et al., 1984
DePuy, C.H.; Bierbaum, V.M.; Damrauer, R.,
Relative Gas-Phase Acidities of the Alkanes,
J. Am. Chem. Soc., 1984, 106, 4051. [all data]
Kistiakowsky, Ruhoff, et al., 1935
Kistiakowsky, G.B.; Ruhoff, J.R.; Smith, H.A.; Vaughan, W.E.,
Heats of organic reactions. II. Hydrogenation of some simpler olefinic hydrocarbons,
J. Am. Chem. Soc., 1935, 57, 876-882. [all data]
Cox and Pilcher, 1970
Cox, J.D.; Pilcher, G.,
Thermochemistry of Organic and Organometallic Compounds, Academic Press, New York, 1970, 1-636. [all data]
Pines, Kvetinskas, et al., 1945
Pines, H.; Kvetinskas, B.; Kassel, L.S.; Ipatieff, V.N.,
Determination of equilibrium constants for butanes and pentanes,
J. Am. Chem. Soc., 1945, 67, 631-637. [all data]
Notes
Go To: Top, Reaction thermochemistry data, References
- Symbols used in this document:
ΔrG° Free energy of reaction at standard conditions ΔrH° Enthalpy of reaction at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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