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
Δfgas-32.07 ± 0.15kcal/molCcbPittam and Pilcher, 1972ALS
Δfgas-32.42 ± 0.13kcal/molCmProsen, Maron, et al., 1951see Prosen and Rossini, 1945, Rossini, 1935; ALS
Quantity Value Units Method Reference Comment
Δcgas-685.71 ± 0.14kcal/molCcbPittam and Pilcher, 1972Corresponding Δfgas = -32.07 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS
Δcgas-685.37 ± 0.11kcal/molCmProsen, Maron, et al., 1951see Prosen and Rossini, 1945, Rossini, 1935; Corresponding Δfgas = -32.41 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
8.32050.Chen S.S., 1975Recommended values are in good agreement with those calculated by [ Pitzer K.S., 1946].; GT
11.30100.
14.41150.
17.17200.
21.49273.15
23.10298.15
23.22300.
29.739400.
35.669500.
40.719600.
45.000700.
48.671800.
51.850900.
54.6011000.
57.0001100.
59.0701200.
60.8801300.
62.4501400.
63.8191500.

Constant pressure heat capacity of gas

Cp,gas (cal/mol*K) Temperature (K) Reference Comment
19.67 ± 0.01243.15Ernst 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
21.50 ± 0.01273.15
22.76 ± 0.024293.15
24.061 ± 0.024313.15
25.423 ± 0.026333.15
26.209347.6
26.707 ± 0.026353.15
26.900359.4
28.590387.5
32.751452.5
36.551520.9
38.549561.7
40.559605.3
44.259692.7

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
liquid47.990cal/mol*KN/AAston, Kennedy, et al., 1940 
liquid47.49cal/mol*KN/AParks, Shomate, et al., 1937Extrapolation below 67 K, 44.02 J/mol*K.

Constant pressure heat capacity of liquid

Cp,liquid (cal/mol*K) Temperature (K) Reference Comment
30.999260.Aston, Kennedy, et al., 1940T = 20 to 260 K.
30.69258.3Parks, Shomate, et al., 1937T = 79 to 261 K. Value is unsmoothed experimental datum.

Phase change 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:
BS - Robert L. Brown and Stephen E. Stein
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
DH - Eugene S. Domalski and Elizabeth D. Hearing
AC - William E. Acree, Jr., James S. Chickos
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

Quantity Value Units Method Reference Comment
Tboil262. ± 2.KAVGN/AAverage of 24 out of 25 values; Individual data points
Quantity Value Units Method Reference Comment
Tfus140. ± 100.KAVGN/AAverage of 7 values; Individual data points
Quantity Value Units Method Reference Comment
Ttriple113.55KN/AYounglove and Ely, 1987Uncertainty assigned by TRC = 0.05 K; TRC
Ttriple113.55KN/AGoodwin and Haynes, 1982Uncertainty assigned by TRC = 0.02 K; TRC
Ttriple113.74KN/AAston, Kennedy, et al., 1940, 2Uncertainty assigned by TRC = 0.07 K; TRC
Ttriple113.2KN/AParks, Shomate, et al., 1937, 2Uncertainty assigned by TRC = 0.2 K; TRC
Quantity Value Units Method Reference Comment
Ptriple1.9226×10-7atmN/AYounglove and Ely, 1987Uncertainty assigned by TRC = 2.×10-10 atm; TRC
Ptriple1.9226×10-7atmN/AGoodwin and Haynes, 1982Uncertainty assigned by TRC = 5.×10-10 atm; TRC
Quantity Value Units Method Reference Comment
Tc407.7 ± 0.8KAVGN/AAverage of 10 values; Individual data points
Quantity Value Units Method Reference Comment
Pc36.0 ± 0.5atmAVGN/AAverage of 9 values; Individual data points
Quantity Value Units Method Reference Comment
Vc0.259l/molN/ADaubert, 1996 
Vc0.2591l/molN/AYounglove and Ely, 1987Uncertainty assigned by TRC = 0.001 l/mol; TRC
Quantity Value Units Method Reference Comment
ρc3.85 ± 0.05mol/lN/ADaubert, 1996 
ρc3.880mol/lN/ALevelt Sengers, Kamgar-Parsi, et al., 1983Uncertainty assigned by TRC = 0.009 mol/l; TRC
ρc3.91mol/lN/AWaxman and Gallagher, 1983Uncertainty assigned by TRC = 0.09 mol/l; TRC
ρc3.8601mol/lN/AGoodwin and Haynes, 1982Uncertainty assigned by TRC = 0.03 mol/l; TRC
ρc3.802mol/lN/ABeattie, Edwards, et al., 1949Uncertainty assigned by TRC = 0.1 mol/l; TRC
Quantity Value Units Method Reference Comment
Δvap4.778kcal/molN/AMajer and Svoboda, 1985 

Enthalpy of vaporization

ΔvapH (kcal/mol) Temperature (K) Method Reference Comment
5.0901261.44N/AAston, Kennedy, et al., 1940P = 101.325 kPa; DH
5.09261.3N/AMajer and Svoboda, 1985 
5.14318.N/ALim, Park, et al., 1999Based on data from 303. to 333. K.; AC
5.35265.AStephenson and Malanowski, 1987Based on data from 186. to 280. K.; AC
6.43172.AStephenson and Malanowski, 1987Based on data from 121. to 187. K.; AC
5.23278.AStephenson and Malanowski, 1987Based on data from 263. to 306. K.; AC
5.11316.AStephenson and Malanowski, 1987Based on data from 301. to 366. K.; AC
5.16376.AStephenson and Malanowski, 1987Based on data from 361. to 408. K.; AC
5.16292.N/ASteele, Poling, et al., 1976Based on data from 277. to 344. K. See also Boublik, Fried, et al., 1984.; AC
5.09286.N/AReid, 1972AC
5.1 ± 0.8261.44VAston, Kennedy, et al., 1940, 3ALS
5.40247.N/AAston, Kennedy, et al., 1940Based on data from 188. to 262. K. See also Boublik, Fried, et al., 1984.; AC

Entropy of vaporization

ΔvapS (cal/mol*K) Temperature (K) Reference Comment
19.47261.44Aston, Kennedy, et al., 1940P; DH

Antoine Equation Parameters

log10(P) = A − (B / (T + C))
    P = vapor pressure (atm)
    T = temperature (K)

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Temperature (K) A B C Reference Comment
261.31 to 408.124.32241132.1080.918Das, Reed, et al., 1973Coefficents calculated by NIST from author's data.
188.06 to 261.543.93846912.141-29.808Aston, Kennedy, et al., 1940Coefficents calculated by NIST from author's data.

Enthalpy of fusion

ΔfusH (kcal/mol) Temperature (K) Reference Comment
1.085113.74Aston, Kennedy, et al., 1940DH
1.07113.7Perkins and Magee, 2009AC
1.09113.7Domalski and Hearing, 1996AC
1.075113.2Parks, Shomate, et al., 1937DH

Entropy of fusion

ΔfusS (cal/mol*K) Temperature (K) Reference Comment
9.541113.74Aston, Kennedy, et al., 1940DH
9.496113.2Parks, Shomate, et al., 1937DH

In addition to the Thermodynamics Research Center (TRC) data available from this site, much more physical and chemical property data is available from the following TRC products:


Henry's Law 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: Rolf Sander

Henry's Law constant (water solution)

kH(T) = H exp(d(ln(kH))/d(1/T) ((1/T) - 1/(298.15 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)

H (mol/(kg*bar)) d(ln(kH))/d(1/T) (K) Method Reference Comment
0.00086 QN/A missing citation give several references for the Henry's law constants but don't assign them to specific species.
0.00084 LN/A 
0.000812700.LN/A 
0.00085 VN/A 

Gas phase ion energetics data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Henry's Law data, IR Spectrum, Mass spectrum (electron ionization), Gas Chromatography, References, Notes

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:
HL - Edward P. Hunter and Sharon G. Lias
L - Sharon G. Lias

Data compiled as indicated in comments:
B - John E. Bartmess
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)10.68 ± 0.11eVN/AN/AL
Quantity Value Units Method Reference Comment
Proton affinity (review)162.0kcal/molN/AHunter and Lias, 1998HL
Quantity Value Units Method Reference Comment
Gas basicity160.4kcal/molN/AHunter and Lias, 1998HL

Ionization energy determinations

IE (eV) Method Reference Comment
10.57ESTLuo and Pacey, 1992LL
10.74 ± 0.05EIFlesch and Svec, 1973LLK
10.69PIDewar and Worley, 1969RDSH
10.79PITurner and Al-Joboury, 1964RDSH
10.78PIAl-Joboury and Turner, 1964RDSH
10.57PIWatanabe, Nakayama, et al., 1962RDSH
~10.5PISteiner, Giese, et al., 1961RDSH
11.13PEKimura, Katsumata, et al., 1981Vertical value; LLK
11.0 ± 0.1PEBieri, Burger, et al., 1977Vertical value; LLK
11.4PEMurrell and Schmidt, 1972Vertical value; LLK

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
CH3+29.4 ± 0.2?EIOlmsted, Street, et al., 1964RDSH
C2H5+13.80C2H5EIOmura, 1961RDSH
C3H5+14.55?EIOmura, 1961RDSH
C3H6+10.89 ± 0.02CH4PIMead, Donchi, et al., 1980LLK
C3H6+10.91CH4EIWolkoff and Holmes, 1978LLK
C3H6+10.93 ± 0.03CH4PISteiner, Giese, et al., 1961RDSH
C3H7+11.16 ± 0.02CH3PIMead, Donchi, et al., 1980LLK
C3H7+11.16 ± 0.05CH3EIWilliams and Hamill, 1968RDSH
C3H7+11.23 ± 0.03CH3PISteiner, Giese, et al., 1961RDSH
C4H9+10.68 ± 0.02HPIMead, Donchi, et al., 1980LLK
C4H9+10.68 ± 0.03HPIMcLoughlin and Traeger, 1979LLK
C4H9+11.6HEIOmura, 1961RDSH

De-protonation reactions

C4H9- + Hydrogen cation = Isobutane

By formula: C4H9- + H+ = C4H10

Quantity Value Units Method Reference Comment
Δr412.9 ± 2.0kcal/molBranDePuy, Gronert, et al., 1989gas phase; B
Δr414.7 ± 4.8kcal/molBranPeerboom, Rademaker, et al., 1992gas phase; B
Quantity Value Units Method Reference Comment
Δr404.3 ± 2.1kcal/molH-TSDePuy, Gronert, et al., 1989gas phase; B
Δr406.1 ± 4.9kcal/molH-TSPeerboom, Rademaker, et al., 1992gas phase; B

C4H9- + Hydrogen cation = Isobutane

By formula: C4H9- + H+ = C4H10

Quantity Value Units Method Reference Comment
Δr413.1 ± 2.0kcal/molBranDePuy, Gronert, et al., 1989gas phase; B
Δr414.0 ± 2.0kcal/molBranDePuy, Bierbaum, et al., 1984gas phase; B
Quantity Value Units Method Reference Comment
Δr405.7 ± 2.1kcal/molH-TSDePuy, Gronert, et al., 1989gas phase; B

IR Spectrum

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Henry's Law data, Gas phase ion energetics data, Mass spectrum (electron ionization), Gas Chromatography, References, Notes

Data compiled by: Coblentz Society, Inc.

Data compiled by: NIST Mass Spectrometry Data Center, William E. Wallace, director


Mass spectrum (electron ionization)

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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: NIST Mass Spectrometry Data Center, William E. Wallace, director

Spectrum

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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

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Gas Chromatography

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Henry's Law data, Gas phase ion energetics data, IR Spectrum, 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 by: NIST Mass Spectrometry Data Center, William E. Wallace, director

Kovats' RI, non-polar column, isothermal

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Column type Active phase Temperature (C) I Reference Comment
CapillaryCP Sil 260.361.1Estel, Mohnke, et al., 1995100. m/0.25 mm/0.25 μm
CapillaryCP Sil 5 CB20.366.Do and Raulin, 199225. m/0.15 mm/2. μm, H2
CapillarySqualane50.366.7Lunskii and Paizanskaya, 1988He; Column length: 50. m; Column diameter: 0.22 mm
CapillarySqualane70.367.4Lunskii and Paizanskaya, 1988He; Column length: 50. m; Column diameter: 0.22 mm
CapillarySE-3060.365.Bredael, 1982Column length: 100. m; Column diameter: 0.5 mm
CapillaryOV-120.365.Nijs and Jacobs, 1981He; Column length: 150. m; Column diameter: 0.50 mm
CapillarySqualane50.364.6Schröder, 1980 
CapillarySqualane100.366.Lulova, Leont'eva, et al., 1976He; Column length: 120. m; Column diameter: 0.25 mm
CapillarySqualane40.371.Matukuma, 1969N2; Column length: 91.4 m; Column diameter: 0.25 mm
PackedSqualane27.365.Hively and Hinton, 1968He, Chromosorb P; Column length: 15. m; Column diameter: 0.25 mm
PackedSqualane49.366.Hively and Hinton, 1968He, Chromosorb P; Column length: 15. m; Column diameter: 0.25 mm
PackedSqualane67.366.Hively and Hinton, 1968He, Chromosorb P; Column length: 15. m; Column diameter: 0.25 mm
PackedSqualane86.366.Hively and Hinton, 1968He, Chromosorb P; Column length: 15. m; Column diameter: 0.25 mm
PackedSE-3070.369.Widmer, 1967Diatoport S; Column length: 7.9 m
PackedSqualane26.363.Zulaïca and Guiochon, 1966Column length: 10. m

Kovats' RI, non-polar column, custom temperature program

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Column type Active phase I Reference Comment
CapillaryPetrocol DH-100366.Haagen-Smit Laboratory, 1997He; Column length: 100. m; Column diameter: 0.2 mm; Program: 5C(10min) => 5C/min => 50C(48min) => 1.5C/min => 195C(91min)
CapillaryDB-1362.Hoekman, 199360. m/0.32 mm/1.0 μm, He; Program: -40 C for 12 min; -40 - 125 C at 3 deg.min; 125-185 C at 6 deg/min; 185 - 220 C at 20 deg/min; hold 220 C for 2 min

Kovats' RI, polar column, isothermal

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Column type Active phase Temperature (C) I Reference Comment
PackedCarbowax 20M130.369.Widmer, 1967Diatoport P; Column length: 7.9 m
PackedCarbowax 20M70.372.Widmer, 1967Diatoport P; Column length: 7.9 m

Van Den Dool and Kratz RI, non-polar column, temperature ramp

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Column type Active phase I Reference Comment
CapillaryOV-101354.2Yin, Liu, et al., 2001N2, 1. K/min; Column length: 80. m; Column diameter: 0.22 mm; Tstart: 30. C; Tend: 130. C
CapillaryPetrocol DH353.99Subramaniam, Bochniak, et al., 1994100. m/0.25 mm/0.5 μm, He, 1. K/min; Tstart: 30. C; Tend: 220. C
CapillaryPetrocol DH353.53White, Douglas, et al., 1992100. m/0.25 mm/0.5 μm, He, 1. K/min; Tstart: 30. C; Tend: 220. C
CapillaryPetrocol DH353.53White, Douglas, et al., 1992100. m/0.25 mm/0.5 μm, He, 1. K/min; Tstart: 30. C; Tend: 220. C
CapillaryPetrocol DH353.White, Hackett, et al., 1992100. m/0.25 mm/0.5 μm, He, 1. K/min; Tstart: 30. C; Tend: 220. C

Van Den Dool and Kratz RI, non-polar column, custom temperature program

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Column type Active phase I Reference Comment
CapillaryOV-101354.Wu and Lu, 1984Program: not specified

Normal alkane RI, non-polar column, isothermal

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Column type Active phase Temperature (C) I Reference Comment
CapillaryMethyl Silicone50.366.N/AN2; Column length: 74.6 m; Column diameter: 0.28 mm
PackedMethyl Silicone50.364.Huguet, 1961Nitrogen, Celite C-22; Column length: 2.5 m

Normal alkane RI, non-polar column, temperature ramp

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Column type Active phase I Reference Comment
CapillaryPolydimethyl siloxane: CP-Sil 5 CB359.Bramston-Cook, 201360. m/0.25 mm/1.0 μm, Helium, 45. C @ 1.45 min, 3.6 K/min, 210. C @ 2.72 min
CapillaryPetrocol DH354.Supelco, 2012100. m/0.25 mm/0.50 μm, Helium, 20. C @ 15. min, 15. K/min, 220. C @ 30. min
CapillaryPONA354.Zhang, Ding, et al., 200950. m/0.20 mm/0.50 μm, Nitrogen, 35. C @ 15. min, 2. K/min, 200. C @ 10. min
CapillaryOV-1354.8Krkosova, Kubinec, et al., 2007100. m/0.32 mm/0.25 μm, Helium, 5. K/min, 310. C @ 5. min; Tstart: 30. C
CapillaryBP-1364.Health Safety Executive, 200050. m/0.22 mm/0.75 μm, He, 5. K/min; Tstart: 50. C; Tend: 200. C
CapillaryDB-1355.Ciccioli, Cecinato, et al., 199260. m/0.32 mm/1.2 μm, He, 30. C @ 10. min, 3. K/min; Tend: 240. C

Normal alkane RI, non-polar column, custom temperature program

View large format table.

Column type Active phase I Reference Comment
CapillaryMethyl Silicone366.Chen and Feng, 2007Program: not specified
CapillaryMethyl Silicone362.Blunden, Aneja, et al., 200560. m/0.32 mm/1.0 μm, Helium; Program: -50 0C (2 min) 8 0C/min -> 200 0C (7.75 min) 25 0C -> 225 0C (8 min)
CapillaryOV-101366.Du and Liang, 2003Program: not specified
CapillaryPONA368.Perkin Elmer Instruments, 2002Column length: 100. m; Phase thickness: 0.50 μm; Program: not specified
CapillaryPolydimethyl siloxanes354.Yin, Guo, et al., 2001Program: not specified
CapillaryMethyl Silicone354.Spieksma, 1999Program: not specified
CapillarySPB-1354.Flanagan, Streete, et al., 199760. m/0.53 mm/5. μm, He; Program: 40C(6min) => 5C/min => 80C => 10C/min => 200C
CapillaryPolydimethyl siloxanes366.Zenkevich and Chupalov, 1996Program: not specified
CapillaryPolydimethyl siloxanes366.Zenkevich and Chupalov, 1996Program: not specified
CapillarySPB-1354.Strete, Ruprah, et al., 199260. m/0.53 mm/5.0 μm, Helium; Program: 40 0C (6 min) 5 0C/min -> 80 0C 10 0C/min -> 200 0C
CapillarySPB-1370.Strete, Ruprah, et al., 199260. m/0.53 mm/5.0 μm, Helium; Program: not specified
CapillaryOV-1370.Ramsey and Flanagan, 1982Program: not specified
PackedApieson L350.Kojima, Fujii, et al., 1980Chromosorb W; Column length: 20. m; Program: not specified
PackedSE-30368.Robinson and Odell, 1971N2, Chromosorb W; Column length: 6.1 m; Program: 50C910min) => 20C/min => 90(6min) => 10C/min => 150C(hold)

References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Henry's Law data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), Gas Chromatography, 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]

Younglove and Ely, 1987
Younglove, B.A.; Ely, J.F., Thermophysical Properties of Fluids II. Methane, Ethane, Propane, Isobutane, and Normal Butane, J. Phys. Chem. Ref. Data, 1987, 16, 577. [all data]

Goodwin and Haynes, 1982
Goodwin, R.D.; Haynes, W.M., Thermophysical Properties of Propane from 85 to 700 K at Pressures to 70 MPa, NBS Monogr. (U. S.) No. 170, 249 pp., 1982. [all data]

Aston, Kennedy, et al., 1940, 2
Aston, J.G.; Kennedy, R.M.; Schumann, S.C., The Heat Capacity and Entropy of Fusion and Vaporization and the Vapor Pressure of Isobutane, J. Am. Chem. Soc., 1940, 62, 2059. [all data]

Parks, Shomate, et al., 1937, 2
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Notes

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