Butane, 2-methyl-

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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
Δfgas-36.73 ± 0.14kcal/molCcbGood, 1970ALS
Δfgas-36.84 ± 0.23kcal/molCmPilcher and Chadwick, 1967ALS
Δfgas-36.92 ± 0.20kcal/molCcbProsen and Rossini, 1945ALS
Quantity Value Units Method Reference Comment
Δcgas-843.31 ± 0.22kcal/molCmPilcher and Chadwick, 1967Corresponding Δfgas = -36.84 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS
Δcgas-843.36 ± 0.15kcal/molCmKnowlton and Rossini, 1939Corresponding Δfgas = -36.79 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS
Δcgas-843.11 ± 0.84kcal/molCcbRoth and Pahlke, 1936Reanalyzed by Cox and Pilcher, 1970, Original value = -843.45 kcal/mol; Corresponding Δfgas = -37.04 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS

Constant pressure heat capacity of gas

Cp,gas (cal/mol*K) Temperature (K) Reference Comment
20.30200.Scott D.W., 1974Recommended values were obtained from the consistent correlation scheme for alkanes [ Scott D.W., 1974, 2, Scott D.W., 1974]. This approach gives a better agreement with experimental data than the statistical thermodynamics calculations [ Pitzer K.S., 1946, Scott D.W., 1951].; GT
26.379273.15
28.41 ± 0.1298.15
28.561300.
36.539400.
43.800500.
50.201600.
55.700700.
60.500800.
64.699900.
68.4011000.
71.5991100.
74.4001200.
77.0001300.
79.0011400.
80.9991500.

Constant pressure heat capacity of gas

Cp,gas (cal/mol*K) Temperature (K) Reference Comment
29.950 ± 0.088317.20Scott D.W., 1951GT
33.25 ± 0.10358.15
36.72 ± 0.11402.30
40.24 ± 0.12449.20
42.93 ± 0.13487.05

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
Δfliquid-42.58 ± 0.21kcal/molCcbGood, 1970Reanalyzed by Pedley, Naylor, et al., 1986, Original value = -42.76 ± 0.14 kcal/mol; ALS
Δfliquid-42.86 ± 0.20kcal/molCcbProsen and Rossini, 1945ALS
Quantity Value Units Method Reference Comment
Δcliquid-837.57 ± 0.20kcal/molCcbGood, 1970Reanalyzed by Pedley, Naylor, et al., 1986, Original value = -837.39 ± 0.11 kcal/mol; Corresponding Δfliquid = -42.58 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS
Δcliquid-837.30 ± 0.18kcal/molCcbProsen and Rossini, 1945Corresponding Δfliquid = -42.85 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS
Quantity Value Units Method Reference Comment
liquid62.239cal/mol*KN/AGuthrie and Huffman, 1943DH
liquid62.390cal/mol*KN/ASchumann, Aston, et al., 1942DH
liquid60.80cal/mol*KN/AParks, Huffman, et al., 1930Extrapolation below 90 K, 57.49 J/mol*K.; DH

Constant pressure heat capacity of liquid

Cp,liquid (cal/mol*K) Temperature (K) Reference Comment
39.32298.3Czarnota, 1988T = 289 to 299 K. p = 0.1 MPa. Unsmoothed experimental datum. Cp values provided over the pressure range 0.1 to 820 MPa.; DH
39.400298.15Guthrie and Huffman, 1943T = 13 to 300 K.; DH
40.490290.Schumann, Aston, et al., 1942T = 20 to 290 K.; DH
37.60275.8Parks, Huffman, et al., 1930T = 80 to 276 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

Hydrogen + 2-Methyl-1-butene = Butane, 2-methyl-

By formula: H2 + C5H10 = C5H12

Quantity Value Units Method Reference Comment
Δr-30.341kcal/molChydDolliver, Gresham, et al., 1937gas phase; At 355 °K
Δr-28.25 ± 0.10kcal/molChydKistiakowsky, Ruhoff, et al., 1936gas phase; Reanalyzed by Cox and Pilcher, 1970, Original value = -28.49 ± 0.36 kcal/mol; At 355 K

Hydrogen + 1-Butene, 3-methyl- = Butane, 2-methyl-

By formula: H2 + C5H10 = C5H12

Quantity Value Units Method Reference Comment
Δr-30.19 ± 0.06kcal/molChydDolliver, Gresham, et al., 1937gas phase; Reanalyzed by Cox and Pilcher, 1970, Original value = -30.34 ± 0.06 kcal/mol; At 355 °K

Pentane = Butane, 2-methyl-

By formula: C5H12 = C5H12

Quantity Value Units Method Reference Comment
Δr-1.861kcal/molEqkPines, Kvetinskas, et al., 1945gas phase; Heat of isomerization

Hydrogen + 2-Butene, 2-methyl- = Butane, 2-methyl-

By formula: H2 + C5H10 = C5H12

Quantity Value Units Method Reference Comment
Δr-26.68 ± 0.06kcal/molChydKistiakowsky, Ruhoff, et al., 1936gas phase

Gas phase ion energetics 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 evaluated as indicated in comments:
L - Sharon G. Lias

Data compiled as indicated in comments:
LL - Sharon G. Lias and Joel F. Liebman
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron

Quantity Value Units Method Reference Comment
IE (evaluated)10.32 ± 0.05eVN/AN/AL

Ionization energy determinations

IE (eV) Method Reference Comment
10.21PITraeger, Hudson, et al., 1996T = 0K; LL
10.18ESTLuo and Pacey, 1992LL
10.22PITraeger, 1981LLK
10.3 ± 0.1PEBieri, Burger, et al., 1977LLK
10.50 ± 0.05EIFlesch and Svec, 1973LLK
10.32PEDewar and Worley, 1969RDSH
10.32PIWatanabe, Nakayama, et al., 1962RDSH
10.94PEKimura, Katsumata, et al., 1981Vertical value; LLK
11.0 ± 0.1PEBieri, Burger, et al., 1977Vertical value; LLK

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
C3H6+10.66C2H6PITraeger, Hudson, et al., 1996T = 0K; LL
C3H6+10.84 ± 0.025C2H6PISteiner, Giese, et al., 1961RDSH
C3H7+11.06C2H5PITraeger, Hudson, et al., 1996T = 0K; LL
C3H7+11.15 ± 0.05C2H5PISteiner, Giese, et al., 1961RDSH
C4H8+10.72CH4PITraeger, Hudson, et al., 1996T = 0K; LL
C4H8+10.74 ± 0.02CH4PISteiner, Giese, et al., 1961RDSH
C4H9+10.96CH3PITraeger, Hudson, et al., 1996T = 0K; LL
C4H9+10.87CH3PITraeger, 1981LLK
C4H9+11.15 ± 0.07CH3PISteiner, Giese, et al., 1961RDSH

References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, 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.

Good, 1970
Good, W.D., The enthalpies of combustion and formation of the isomeric pentanes, J. Chem. Thermodyn., 1970, 2, 237-244. [all data]

Pilcher and Chadwick, 1967
Pilcher, G.; Chadwick, J.D.M., Measurements of heats of combustion by flame calorimetry. Part 4.-n-Pentane, isopentane, neopentane, Trans. Faraday Soc., 1967, 63, 2357-2361. [all data]

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]

Knowlton and Rossini, 1939
Knowlton, J.W.; Rossini, F.D., Heats of combustion of tetramethylmethane and 2-methylbutane, J. Res. NBS, 1939, 22, 415-424. [all data]

Roth and Pahlke, 1936
Roth, W.A.; Pahlke, H., Sekundare eichsubstanz fur verbrennungscalorimeter fur gase und dampfe. Die verbrennungswarme von isopentandampf, Angew. Chem., 1936, 49, 618-619. [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]

Scott D.W., 1974
Scott D.W., Chemical Thermodynamic Properties of Hydrocarbons and Related Substances. Properties of the Alkane Hydrocarbons, C1 through C10 in the Ideal Gas State from 0 to 1500 K. U.S. Bureau of Mines, Bulletin 666, 1974. [all data]

Scott D.W., 1974, 2
Scott D.W., Correlation of the chemical thermodynamic properties of alkane hydrocarbons, J. Chem. Phys., 1974, 60, 3144-3165. [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]

Scott D.W., 1951
Scott D.W., Rotational isomerism and thermodynamic functions of 2-methylbutane and 2,3-dimethylbutane. Vapor heat capacity and heat of vaporization of 2-methylbutane, J. Am. Chem. Soc., 1951, 73, 1707-1712. [all data]

Pedley, Naylor, et al., 1986
Pedley, J.B.; Naylor, R.D.; Kirby, S.P., Thermochemical Data of Organic Compounds, Chapman and Hall, New York, 1986, 1-792. [all data]

Guthrie and Huffman, 1943
Guthrie, G.B., Jr.; Huffman, H.M., Thermal data. XVI. The heat capacity and entropy of isopentane. The absence of a reported anomaly, J. Am. Chem. Soc., 1943, 65, 1139-1143. [all data]

Schumann, Aston, et al., 1942
Schumann, S.C.; Aston, J.G.; Sagenkahn, M., The heat capacity and entropy, heats of fusion and vaporization and the vapor pressures of isopentane, J. Am. Chem. Soc., 1942, 64, 1039-1043. [all data]

Parks, Huffman, et al., 1930
Parks, G.S.; Huffman, H.M.; Thomas, S.B., Thermal data on organic compounds. VI. The heat capacities, entropies and free energies of some saturated, non-benzenoid hydrocarbons, J. Am. Chem. Soc., 1930, 52, 1032-1041. [all data]

Czarnota, 1988
Czarnota, I., Heat capacity of 2-methylbutane at high pressures, J. Chem. Thermodynam., 1988, 20, 457-462. [all data]

Dolliver, Gresham, et al., 1937
Dolliver, M.a.; Gresham, T.L.; Kistiakowsky, G.B.; Vaughan, W.E., Heats of organic reactions. V. Heats of hydrogenation of various hydrocarbons, J. Am. Chem. Soc., 1937, 59, 831-841. [all data]

Kistiakowsky, Ruhoff, et al., 1936
Kistiakowsky, G.B.; Ruhoff, J.R.; Smith, H.A.; Vaughan, W.E., Heats of organic reactions. III. Hydrogenation of some higher olefins, J. Am. Chem. Soc., 1936, 58, 137-145. [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]

Traeger, Hudson, et al., 1996
Traeger, J.C.; Hudson, C.E.; McAdoo, D.J., A photoionization study of the ion-neutral complexes [CH3CH+CH3CH2CH3] and [CH3CH2CH+CH3CH3] in the gas phase: Formation, H-transfer and C-C bond formation between partners, and channeling of energy into dissociation, J. Am. Soc. Mass Spectrom., 1996, 7, 73. [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]

Traeger, 1981
Traeger, J.C., Heat of formation of sec-butyl cation in the gas phase, Org. Mass Spectrom., 1981, 16, 193. [all data]

Bieri, Burger, et al., 1977
Bieri, G.; Burger, F.; Heilbronner, E.; Maier, J.P., Valence ionization enrgies of hydrocarbons, Helv. Chim. Acta, 1977, 60, 2213. [all data]

Flesch and Svec, 1973
Flesch, G.D.; Svec, H.J., Fragmentation reactions in the mass spectrometer for C2-C5 alkanes, J. Chem. Soc. Faraday Trans. 2, 1973, 69, 1187. [all data]

Dewar and Worley, 1969
Dewar, M.J.S.; Worley, S.D., Photoelectron spectra of molecules. I. Ionization potentials of some organic molecules and their interpretation, J. Chem. Phys., 1969, 50, 654. [all data]

Watanabe, Nakayama, et al., 1962
Watanabe, K.; Nakayama, T.; Mottl, J., Ionization potentials of some molecules, J. Quant. Spectry. Radiative Transfer, 1962, 2, 369. [all data]

Kimura, Katsumata, et al., 1981
Kimura, K.; Katsumata, S.; Achiba, Y.; Yamazaki, T.; Iwata, S., Ionization energies, Ab initio assignments, and valence electronic structure for 200 molecules in Handbook of HeI Photoelectron Spectra of Fundamental Organic Compounds, Japan Scientific Soc. Press, Tokyo, 1981. [all data]

Steiner, Giese, et al., 1961
Steiner, B.; Giese, C.F.; Inghram, M.G., Photoionization of alkanes. Dissociation of excited molecular ions, J. Chem. Phys., 1961, 34, 189. [all data]


Notes

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, References