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, Mass spectrum (electron ionization), 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° | 412.9 ± 2.0 | kcal/mol | Bran | DePuy, Gronert, et al., 1989 | gas phase; B |
ΔrH° | 414.7 ± 4.8 | kcal/mol | Bran | Peerboom, Rademaker, et al., 1992 | gas phase; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 404.3 ± 2.1 | kcal/mol | H-TS | DePuy, Gronert, et al., 1989 | gas phase; B |
ΔrG° | 406.1 ± 4.9 | kcal/mol | H-TS | Peerboom, Rademaker, et al., 1992 | gas phase; B |
C4H9- + =
By formula: C4H9- + H+ = C4H10
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 413.1 ± 2.0 | kcal/mol | Bran | DePuy, Gronert, et al., 1989 | gas phase; B |
ΔrH° | 414.0 ± 2.0 | kcal/mol | Bran | DePuy, Bierbaum, et al., 1984 | gas phase; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 405.7 ± 2.1 | kcal/mol | H-TS | DePuy, Gronert, et al., 1989 | gas phase; B |
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -28.15 ± 0.10 | kcal/mol | Chyd | Kistiakowsky, Ruhoff, et al., 1935 | gas phase; Reanalyzed by Cox and Pilcher, 1970, Original value = -28.39 ± 0.18 kcal/mol; At 355 °K; ALS |
By formula: C4H10 = C4H10
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -2.318 | kcal/mol | Eqk | Pines, Kvetinskas, et al., 1945 | gas phase; Heat of isomerization; ALS |
Mass spectrum (electron ionization)
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 compiled by: NIST Mass Spectrometry Data Center, William E. Wallace, director
Spectrum
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Additional Data
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Due to licensing restrictions, this spectrum cannot be downloaded.
Owner | NIST Mass Spectrometry Data Center Collection (C) 2014 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved. |
---|---|
NIST MS number | 121 |
References
Go To: Top, Reaction thermochemistry data, Mass spectrum (electron ionization), 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, Mass spectrum (electron ionization), 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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