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Isobutane

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Gas 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
GT - Glushko Thermocenter, Russian Academy of Sciences, Moscow

Quantity Value Units Method Reference Comment
Deltafgas-134.2 ± 0.63kJ/molCcbPittam and Pilcher, 1972ALS
Deltafgas-135.6 ± 0.54kJ/molCmProsen, Maron, et al., 1951see Prosen and Rossini, 1945, Rossini, 1935; ALS
Quantity Value Units Method Reference Comment
Deltacgas-2869.0 ± 0.59kJ/molCcbPittam and Pilcher, 1972Corresponding «DELTA»fgas = -134.2 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS
Deltacgas-2867.6 ± 0.46kJ/molCmProsen, Maron, et al., 1951see Prosen and Rossini, 1945, Rossini, 1935; Corresponding «DELTA»fgas = -135.6 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
34.8150.Chen S.S., 1975Recommended values are in good agreement with those calculated by [ Pitzer K.S., 1946].; GT
47.28100.
60.29150.
71.84200.
89.91273.15
96.65298.15
97.15300.
124.43400.
149.24500.
170.37600.
188.28700.
203.64800.
216.94900.
228.451000.
238.491100.
247.151200.
254.721300.
261.291400.
267.021500.

Constant pressure heat capacity of gas

Cp,gas (J/mol*K) Temperature (K) Reference Comment
82.30 ± 0.06243.15Ernst G., 1970Other experimental values of heat capacity [ Sage B.H., 1937, Sage B.H., 1938] are less accurate, see [ Chen S.S., 1975]. Please also see Dailey B.P., 1943, Wacker P.F., 1947.; GT
89.97 ± 0.06273.15
95.21 ± 0.10293.15
100.67 ± 0.10313.15
106.37 ± 0.11333.15
109.66347.6
111.74 ± 0.11353.15
112.55359.4
119.62387.5
137.03452.5
152.93520.9
161.29561.7
169.70605.3
185.18692.7

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 by: Eugene S. Domalski and Elizabeth D. Hearing

Quantity Value Units Method Reference Comment
liquid200.79J/mol*KN/AAston, Kennedy, et al., 1940 
liquid198.7J/mol*KN/AParks, Shomate, et al., 1937Extrapolation below 67 K, 44.02 J/mol*K.

Constant pressure heat capacity of liquid

Cp,liquid (J/mol*K) Temperature (K) Reference Comment
129.70260.Aston, Kennedy, et al., 1940T = 20 to 260 K.
128.4258.3Parks, Shomate, et al., 1937T = 79 to 261 K. Value is unsmoothed experimental datum.

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 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- + Hydrogen cation = Isobutane

By formula: C4H9- + H+ = C4H10

Quantity Value Units Method Reference Comment
Deltar1728. ± 8.4kJ/molBranDePuy, Gronert, et al., 1989gas phase; B
Deltar1735. ± 20.kJ/molBranPeerboom, Rademaker, et al., 1992gas phase; B
Quantity Value Units Method Reference Comment
Deltar1692. ± 8.8kJ/molH-TSDePuy, Gronert, et al., 1989gas phase; B
Deltar1699. ± 21.kJ/molH-TSPeerboom, Rademaker, et al., 1992gas phase; B

C4H9- + Hydrogen cation = Isobutane

By formula: C4H9- + H+ = C4H10

Quantity Value Units Method Reference Comment
Deltar1728. ± 8.4kJ/molBranDePuy, Gronert, et al., 1989gas phase; B
Deltar1732. ± 8.4kJ/molBranDePuy, Bierbaum, et al., 1984gas phase; B
Quantity Value Units Method Reference Comment
Deltar1697. ± 8.8kJ/molH-TSDePuy, Gronert, et al., 1989gas phase; B

1-Propene, 2-methyl- + Hydrogen = Isobutane

By formula: C4H8 + H2 = C4H10

Quantity Value Units Method Reference Comment
Deltar-117.8 ± 0.42kJ/molChydKistiakowsky, Ruhoff, et al., 1935gas phase; Reanalyzed by Cox and Pilcher, 1970, Original value = -118.78 ± 0.75 kJ/mol; At 355 °K; ALS

Butane = Isobutane

By formula: C4H10 = C4H10

Quantity Value Units Method Reference Comment
Deltar-9.699kJ/molEqkPines, Kvetinskas, et al., 1945gas phase; Heat of isomerization; ALS

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.

Pittam and Pilcher, 1972
Pittam, D.A.; Pilcher, G., Measurements of heats of combustion by flame calorimetry. Part 8.-Methane, ethane, propane, n-butane and 2-methylpropane, J. Chem. Soc. Faraday Trans. 1, 1972, 68, 2224-2229. [all data]

Prosen, Maron, et al., 1951
Prosen, E.J.; Maron, F.W.; Rossini, F.D., Heats of combustion, formation, and insomerization of ten C4 hydrocarbons, J. Res. NBS, 1951, 46, 106-112. [all data]

Prosen and Rossini, 1945
Prosen, E.J.; Rossini, F.D., Heats of formation and combustion of 1,3-butadiene and styrene, J. Res. NBS, 1945, 34, 59-63. [all data]

Rossini, 1935
Rossini, F.D., Heat of combustion of isobutane, J. Res. NBS, 1935, 15, 357-361. [all data]

Chen S.S., 1975
Chen S.S., Ideal gas thermodynamic properties and isomerization of n-butane and isobutane, J. Phys. Chem. Ref. Data, 1975, 4, 859-869. [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]

Ernst G., 1970
Ernst G., Ideal and real gas state heat capacities Cp of C3H8, i-C4H10, C2F5Cl, CH2ClCF3, CF2ClCFCl2, and CHF2Cl, J. Chem. Thermodyn., 1970, 2, 787-791. [all data]

Sage B.H., 1937
Sage B.H., Phase equilibria in hydrocarbon systems. XX. Isobaric heat capacity of gaseous propane, n-butane, isobutane, and n-pentane, Ind. Eng. Chem., 1937, 29, 1309-1314. [all data]

Sage B.H., 1938
Sage B.H., Phase equilibrium in hydrocarbon systems. Thermodynamic properties of isobutane, Ind. Eng. Chem., 1938, 30, 673-681. [all data]

Dailey B.P., 1943
Dailey B.P., Heat capacities and hindered rotation in n-butane and isobutane, J. Am. Chem. Soc., 1943, 65, 44-46. [all data]

Wacker P.F., 1947
Wacker P.F., Heat capacities of gaseous oxygen, isobutane, and 1-butene from -30 to +90 C, J. Res. Nat. Bur. Stand., 1947, 38, 651-659. [all data]

Aston, Kennedy, et al., 1940
Aston, J.G.; Kennedy, R.M.; Schumann, S.C., The heat capacity and entropy, heats of fusion and vaporization and the vapor pressure of isobutane, J. Am. Chem. Soc., 1940, 62, 2059-2063. [all data]

Parks, Shomate, et al., 1937
Parks, G.S.; Shomate, C.H.; Kennedy, W.D.; Crawford, B.L., Jr., The entropies of n-butane and isobutane, with some heat capacity data for isobutane, J. Chem. Phys., 1937, 5, 359-363. [all data]

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

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