Butane, 2-methyl-
- Formula: C5H12
- Molecular weight: 72.1488
- IUPAC Standard InChIKey: QWTDNUCVQCZILF-UHFFFAOYSA-N
- CAS Registry Number: 78-78-4
- Chemical structure:
This structure is also available as a 2d Mol file or as a computed 3d SD file
View 3d structure (requires JavaScript / HTML 5) - Other names: iso-Pentane; 1,1,2-Trimethylethane; 2-Methylbutane; iso-C5H12; Ethyldimethylmethane; Isoamylhydride; Exxsol isopentane S; 1,1-Dimethylpropane; Methylbutane; NSC 119476
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Condensed phase thermochemistry data
Go To: Top, 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
DH - Eugene S. Domalski and Elizabeth D. Hearing
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔfH°liquid | -42.58 ± 0.21 | kcal/mol | Ccb | Good, 1970 | Reanalyzed by Pedley, Naylor, et al., 1986, Original value = -42.76 ± 0.14 kcal/mol; ALS |
ΔfH°liquid | -42.86 ± 0.20 | kcal/mol | Ccb | Prosen and Rossini, 1945 | ALS |
Quantity | Value | Units | Method | Reference | Comment |
ΔcH°liquid | -837.57 ± 0.20 | kcal/mol | Ccb | Good, 1970 | Reanalyzed by Pedley, Naylor, et al., 1986, Original value = -837.39 ± 0.11 kcal/mol; Corresponding ΔfHºliquid = -42.58 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS |
ΔcH°liquid | -837.30 ± 0.18 | kcal/mol | Ccb | Prosen and Rossini, 1945 | Corresponding ΔfHºliquid = -42.85 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS |
Quantity | Value | Units | Method | Reference | Comment |
S°liquid | 62.239 | cal/mol*K | N/A | Guthrie and Huffman, 1943 | DH |
S°liquid | 62.390 | cal/mol*K | N/A | Schumann, Aston, et al., 1942 | DH |
S°liquid | 60.80 | cal/mol*K | N/A | Parks, Huffman, et al., 1930 | Extrapolation below 90 K, 57.49 J/mol*K.; DH |
Constant pressure heat capacity of liquid
Cp,liquid (cal/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
39.32 | 298.3 | Czarnota, 1988 | T = 289 to 299 K. p = 0.1 MPa. Unsmoothed experimental datum. Cp values provided over the pressure range 0.1 to 820 MPa.; DH |
39.400 | 298.15 | Guthrie and Huffman, 1943 | T = 13 to 300 K.; DH |
40.490 | 290. | Schumann, Aston, et al., 1942 | T = 20 to 290 K.; DH |
37.60 | 275.8 | Parks, Huffman, et al., 1930 | T = 80 to 276 K. Value is unsmoothed experimental datum.; DH |
Reaction thermochemistry data
Go To: Top, Condensed phase 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 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: H2 + C5H10 = C5H12
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -30.341 | kcal/mol | Chyd | Dolliver, Gresham, et al., 1937 | gas phase; At 355 °K |
ΔrH° | -28.25 ± 0.10 | kcal/mol | Chyd | Kistiakowsky, Ruhoff, et al., 1936 | gas phase; Reanalyzed by Cox and Pilcher, 1970, Original value = -28.49 ± 0.36 kcal/mol; At 355 K |
By formula: H2 + C5H10 = C5H12
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -30.19 ± 0.06 | kcal/mol | Chyd | Dolliver, Gresham, et al., 1937 | gas phase; Reanalyzed by Cox and Pilcher, 1970, Original value = -30.34 ± 0.06 kcal/mol; At 355 °K |
By formula: C5H12 = C5H12
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -1.861 | kcal/mol | Eqk | Pines, Kvetinskas, et al., 1945 | gas phase; Heat of isomerization |
By formula: H2 + C5H10 = C5H12
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -26.68 ± 0.06 | kcal/mol | Chyd | Kistiakowsky, Ruhoff, et al., 1936 | gas phase |
Henry's Law data
Go To: Top, Condensed phase thermochemistry data, 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: 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 |
---|---|---|---|---|
0.00072 | Q | N/A | missing citation give several references for the Henry's law constants but don't assign them to specific species. | |
0.00073 | L | N/A |
References
Go To: Top, 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.
Good, 1970
Good, W.D.,
The enthalpies of combustion and formation of the isomeric pentanes,
J. Chem. Thermodyn., 1970, 2, 237-244. [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]
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]
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]
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, 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°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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