Isobutane

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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.

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
Ptriple1.9481×10-7barN/AYounglove and Ely, 1987Uncertainty assigned by TRC = 2.×10-10 bar; TRC
Ptriple1.9481×10-7barN/AGoodwin and Haynes, 1982Uncertainty assigned by TRC = 5.×10-10 bar; TRC
Quantity Value Units Method Reference Comment
Tc407.7 ± 0.8KAVGN/AAverage of 10 values; Individual data points
Quantity Value Units Method Reference Comment
Pc36.5 ± 0.5barAVGN/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
Δvap19.99kJ/molN/AMajer and Svoboda, 1985 

Enthalpy of vaporization

ΔvapH (kJ/mol) Temperature (K) Method Reference Comment
21.297261.44N/AAston, Kennedy, et al., 1940P = 101.325 kPa; DH
21.3261.3N/AMajer and Svoboda, 1985 
21.5318.N/ALim, Park, et al., 1999Based on data from 303. to 333. K.; AC
22.4265.AStephenson and Malanowski, 1987Based on data from 186. to 280. K.; AC
26.9172.AStephenson and Malanowski, 1987Based on data from 121. to 187. K.; AC
21.9278.AStephenson and Malanowski, 1987Based on data from 263. to 306. K.; AC
21.4316.AStephenson and Malanowski, 1987Based on data from 301. to 366. K.; AC
21.6376.AStephenson and Malanowski, 1987Based on data from 361. to 408. K.; AC
21.6292.N/ASteele, Poling, et al., 1976Based on data from 277. to 344. K. See also Boublik, Fried, et al., 1984.; AC
21.3286.N/AReid, 1972AC
21. ± 3.261.44VAston, Kennedy, et al., 1940, 3ALS
22.6247.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 (J/mol*K) Temperature (K) Reference Comment
81.46261.44Aston, Kennedy, et al., 1940P; DH

Antoine Equation Parameters

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

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Temperature (K) A B C Reference Comment
261.31 to 408.124.32811132.1080.918Das, Reed, et al., 1973Coefficents calculated by NIST from author's data.
188.06 to 261.543.94417912.141-29.808Aston, Kennedy, et al., 1940Coefficents calculated by NIST from author's data.

Enthalpy of fusion

ΔfusH (kJ/mol) Temperature (K) Reference Comment
4.540113.74Aston, Kennedy, et al., 1940DH
4.49113.7Perkins and Magee, 2009AC
4.56113.7Domalski and Hearing, 1996AC
4.498113.2Parks, Shomate, et al., 1937DH

Entropy of fusion

ΔfusS (J/mol*K) Temperature (K) Reference Comment
39.92113.74Aston, Kennedy, et al., 1940DH
39.73113.2Parks, 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:


References

Go To: Top, Condensed phase thermochemistry data, Phase change data, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

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
Parks, G.S.; Shomate, C.H.; Kennedy, W.D.; Crawford, B.L., The entropies of n-butane and isobutane with some heat capacity data for isobutane, J. Chem. Phys., 1937, 5, 359-63. [all data]

Daubert, 1996
Daubert, T.E., Vapor-Liquid Critical Properties of Elements and Compounds. 5. Branched Alkanes and Cycloalkanes, J. Chem. Eng. Data, 1996, 41, 365-372. [all data]

Levelt Sengers, Kamgar-Parsi, et al., 1983
Levelt Sengers, J.M.H.; Kamgar-Parsi, B.; Sengers, J.V., Thermodnamic Properties of Isobutane in the Critical Region, J. Chem. Eng. Data, 1983, 28, 354-362. [all data]

Waxman and Gallagher, 1983
Waxman, M.; Gallagher, J.S., Thermodynamic Properties of Isobutane for Temperatures from 250 to 600 K and Pressures from 0.1 to 40 MPa, J. Chem. Eng. Data, 1983, 28, 224. [all data]

Beattie, Edwards, et al., 1949
Beattie, J.A.; Edwards, D.G.; Marple, S., The Vapor Pressure, Orthobaric Liquid Density, and Critical Constants of Isobutane, J. Chem. Phys., 1949, 17, 576. [all data]

Majer and Svoboda, 1985
Majer, V.; Svoboda, V., Enthalpies of Vaporization of Organic Compounds: A Critical Review and Data Compilation, Blackwell Scientific Publications, Oxford, 1985, 300. [all data]

Lim, Park, et al., 1999
Lim, Jong Sung; Park, Ji-Young; Lee, Byung-Gwon; Lee, Youn-Woo; Kim, Jae-Duck, Phase Equilibria of CFC Alternative Refrigerant Mixtures: Binary Systems of Isobutane + 1,1,1,2-Tetrafluoroethane, + 1,1-Difluoroethane, and + Difluoromethane, J. Chem. Eng. Data, 1999, 44, 6, 1226-1230, https://doi.org/10.1021/je9900777 . [all data]

Stephenson and Malanowski, 1987
Stephenson, Richard M.; Malanowski, Stanislaw, Handbook of the Thermodynamics of Organic Compounds, 1987, https://doi.org/10.1007/978-94-009-3173-2 . [all data]

Steele, Poling, et al., 1976
Steele, Kevin; Poling, Bruce E.; Manley, David B., Vapor pressures for the system 1-butene, isobutane, and 1,3-butadiene, J. Chem. Eng. Data, 1976, 21, 4, 399-403, https://doi.org/10.1021/je60071a006 . [all data]

Boublik, Fried, et al., 1984
Boublik, T.; Fried, V.; Hala, E., The Vapour Pressures of Pure Substances: Selected Values of the Temperature Dependence of the Vapour Pressures of Some Pure Substances in the Normal and Low Pressure Region, 2nd ed., Elsevier, New York, 1984, 972. [all data]

Reid, 1972
Reid, Robert C., Handbook on vapor pressure and heats of vaporization of hydrocarbons and related compounds, R. C. Wilhort and B. J. Zwolinski, Texas A Research Foundation. College Station, Texas(1971). 329 pages.$10.00, AIChE J., 1972, 18, 6, 1278-1278, https://doi.org/10.1002/aic.690180637 . [all data]

Aston, Kennedy, et al., 1940, 3
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, 2059-20. [all data]

Das, Reed, et al., 1973
Das, T.R.; Reed, C.O., Jr.; Eubank, P.T., PVT Surface and Thermodynamic Properties of Isobutane, J. Chem. Eng. Data, 1973, 18, 3, 253-262, https://doi.org/10.1021/je60058a001 . [all data]

Perkins and Magee, 2009
Perkins, Richard A.; Magee, Joseph W., Molar Heat Capacity at Constant Volume for Isobutane at Temperatures from (114 to 345) K and at Pressures to 35 MPa «8224» «8225», J. Chem. Eng. Data, 2009, 54, 9, 2646-2655, https://doi.org/10.1021/je9001575 . [all data]

Domalski and Hearing, 1996
Domalski, Eugene S.; Hearing, Elizabeth D., Heat Capacities and Entropies of Organic Compounds in the Condensed Phase. Volume III, J. Phys. Chem. Ref. Data, 1996, 25, 1, 1, https://doi.org/10.1063/1.555985 . [all data]


Notes

Go To: Top, Condensed phase thermochemistry data, Phase change data, References