Butane, 2,2-dimethyl-

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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-44.35 ± 0.23kcal/molCcbProsen and Rossini, 1945ALS
Quantity Value Units Method Reference Comment
gas85.72 ± 0.20cal/mol*KN/AKilpatrick J.E., 1946The entropy values S(296.05 K)=357.19 and S(322.85 K)=369.87 J/mol*K were calculated by [ Scott D.W., 1974] from the experimental data [ Douslin D.R., 1946].; GT

Constant pressure heat capacity of gas

Cp,gas (cal/mol*K) Temperature (K) Reference Comment
24.250200.Scott D.W., 1974, 2Recommended values were obtained from the consistent correlation scheme for alkanes [ Scott D.W., 1974, Scott D.W., 1974, 2]. This approach gives a better agreement with experimental data than the statistical thermodynamics calculation [ Pitzer K.S., 1946] (see also [ Waddington G., 1949]).; GT
31.329273.15
33.81 ± 0.07298.15
34.001300.
43.769400.
52.660500.
60.500600.
67.299700.
73.301800.
78.499900.
83.2001000.
87.2991100.
90.9011200.
94.0011300.
97.0001400.
100.001500.

Constant pressure heat capacity of gas

Cp,gas (cal/mol*K) Temperature (K) Reference Comment
38.100 ± 0.076341.55Waddington G., 1947GT
39.250 ± 0.079353.20
41.501 ± 0.084376.05
44.950 ± 0.091412.40
48.329 ± 0.096449.40

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
AC - William E. Acree, Jr., James S. Chickos
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
CAL - James S. Chickos, William E. Acree, Jr., Joel F. Liebman, Students of Chem 202 (Introduction to the Literature of Chemistry), University of Missouri -- St. Louis
DH - Eugene S. Domalski and Elizabeth D. Hearing

Quantity Value Units Method Reference Comment
Tboil322.9 ± 0.1KAVGN/AAverage of 46 out of 54 values; Individual data points
Quantity Value Units Method Reference Comment
Tfus173. ± 2.KAVGN/AAverage of 24 out of 28 values; Individual data points
Quantity Value Units Method Reference Comment
Ttriple174. ± 2.KAVGN/AAverage of 6 values; Individual data points
Quantity Value Units Method Reference Comment
Tc489.0 ± 0.5KAVGN/AAverage of 7 values; Individual data points
Quantity Value Units Method Reference Comment
Pc30.6 ± 0.2atmN/ADaubert, 1996 
Pc30.6179atmN/AGenco, Teja, et al., 1980Uncertainty assigned by TRC = 0.05 atm; TRC
Pc30.61atmN/AKay and Young, 1975Uncertainty assigned by TRC = 0.03 atm; TRC
Pc30.6700atmN/AKay, 1946Uncertainty assigned by TRC = 0.09998 atm; TRC
Quantity Value Units Method Reference Comment
Vc0.358l/molN/ADaubert, 1996 
Vc0.358l/molN/AGenco, Teja, et al., 1980Uncertainty assigned by TRC = 0.001 l/mol; TRC
Quantity Value Units Method Reference Comment
ρc2.80 ± 0.02mol/lN/ADaubert, 1996 
ρc2.79mol/lN/AKay, 1946Uncertainty assigned by TRC = 0.02 mol/l; by extrapolation of rectilinear diameter to Tc; TRC
Quantity Value Units Method Reference Comment
Δvap6.675kcal/molN/AMajer and Svoboda, 1985 
Δvap6.62kcal/molN/AReid, 1972AC
Δvap6.616kcal/molCOsborne and Ginnings, 1947ALS

Enthalpy of vaporization

ΔvapH (kcal/mol) Temperature (K) Method Reference Comment
6.288322.9N/AMajer and Svoboda, 1985 
6.86288.N/ANicolini and Laffitte, 1949Based on data from 273. to 318. K. See also Boublik, Fried, et al., 1984.; AC
6.64 ± 0.02296.CWaddington and Douslin, 1947AC
6.29 ± 0.02323.CWaddington and Douslin, 1947AC
6.98274.N/AKilpatrick and Pitzer, 1946Based on data from 211. to 289. K.; AC
6.76303.MMWillingham, Taylor, et al., 1945Based on data from 288. to 323. K.; AC

Enthalpy of vaporization

ΔvapH = A exp(-βTr) (1 − Tr)β
    ΔvapH = Enthalpy of vaporization (at saturation pressure) (kcal/mol)
    Tr = reduced temperature (T / Tc)

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Temperature (K) A (kcal/mol) β Tc (K) Reference Comment
296. to 323.10.020.2675488.7Majer and Svoboda, 1985 

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
210.99 to 289.383.73251022.204-49.529Kilpatrick and Pitzer, 1946Coefficents calculated by NIST from author's data.
288.53 to 323.683.874021081.176-43.807Williamham, Taylor, et al., 1945 

Enthalpy of fusion

ΔfusH (kcal/mol) Temperature (K) Reference Comment
0.14174.3Domalski and Hearing, 1996AC

Entropy of fusion

ΔfusS (cal/mol*K) Temperature (K) Reference Comment
10.17126.8Domalski and Hearing, 1996CAL
0.483140.8
0.791174.3

Enthalpy of phase transition

ΔHtrs (kcal/mol) Temperature (K) Initial Phase Final Phase Reference Comment
1.293126.81crystaline, IIIcrystaline, IIDouslin and Huffman, 1946DH
0.06819140.79crystaline, IIcrystaline, IDouslin and Huffman, 1946DH
0.1384174.28crystaline, IliquidDouslin and Huffman, 1946DH
1.289126.81crystaline, IIIcrystaline, IIKilpatrick and Pitzer, 1946DH
0.0676140.88crystaline, IIcrystaline, IKilpatrick and Pitzer, 1946DH
0.138174.66crystaline, IliquidKilpatrick and Pitzer, 1946DH
1.095127.11crystaline, IIcrystaline, IStull, 1937DH
0.111172.13crystaline, IliquidStull, 1937DH

Entropy of phase transition

ΔStrs (cal/mol*K) Temperature (K) Initial Phase Final Phase Reference Comment
10.20126.81crystaline, IIIcrystaline, IIDouslin and Huffman, 1946DH
0.485140.79crystaline, IIcrystaline, IDouslin and Huffman, 1946DH
0.793174.28crystaline, IliquidDouslin and Huffman, 1946DH
10.2126.81crystaline, IIIcrystaline, IIKilpatrick and Pitzer, 1946DH
0.480140.88crystaline, IIcrystaline, IKilpatrick and Pitzer, 1946DH
0.796174.66crystaline, IliquidKilpatrick and Pitzer, 1946DH
8.614127.11crystaline, IIcrystaline, IStull, 1937DH
0.645172.13crystaline, IliquidStull, 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:


Mass spectrum (electron ionization)

Go To: Top, Gas phase thermochemistry data, Phase change 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: NIST Mass Spectrometry Data Center, William E. Wallace, director

Spectrum

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Mass spectrum
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Additional Data

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Owner NIST Mass Spectrometry Data Center
Collection (C) 2014 copyright by the U.S. Secretary of Commerce
on behalf of the United States of America. All rights reserved.
Origin Japan AIST/NIMC Database- Spectrum MS-NW-1294
NIST MS number 227826

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References

Go To: Top, Gas phase thermochemistry data, Phase change data, Mass spectrum (electron ionization), Notes

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

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]

Kilpatrick J.E., 1946
Kilpatrick J.E., The thermodynamics of 2,2-dimethylbutane, including the heat capacity, heats of transition, fusion and vaporization and the entropy, J. Am. Chem. Soc., 1946, 68, 1066-1072. [all data]

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

Douslin D.R., 1946
Douslin D.R., Low-temperature thermal data on the five isomeric hexanes, J. Am. Chem. Soc., 1946, 68, 1704-1708. [all data]

Scott D.W., 1974, 2
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]

Pitzer K.S., 1946
Pitzer K.S., The entropies and related properties of branched paraffin hydrocarbons, Chem. Rev., 1946, 39, 435-447. [all data]

Waddington G., 1949
Waddington G., Experimental vapor heat capacities and heats of vaporization of 2-methylpentane, 3-methylpentane, and 2,3-dimethylbutane, J. Am. Chem. Soc., 1949, 71, 3902-3906. [all data]

Waddington G., 1947
Waddington G., Experimental vapor heat capacities and heats of vaporization of n-hexane and 2,2-dimethylbutane, J. Am. Chem. Soc., 1947, 69, 2275-2279. [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]

Genco, Teja, et al., 1980
Genco, J.M.; Teja, A.S.; Kay, W.B., Study of the critical and azeotropic behavior of binary mixtures I critical states of perfluoromethylcyclohexane + isomeric hexane systems, J. Chem. Eng. Data, 1980, 25, 350. [all data]

Kay and Young, 1975
Kay, W.B.; Young, C.L., Gas-liquid critical properties. Tetradecafluoromethylcyclohexane( perfluoromethylcyclohexane)-2,2-dimethylbutane, Int. DATA Ser., Sel. Data Mixtures, Ser. A, 1975, No. 1, 58. [all data]

Kay, 1946
Kay, W.B., The Vapor Pressures and Saturated Liquid and Vapor Densities of the Isomeric Hexanes, J. Am. Chem. Soc., 1946, 68, 1336. [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]

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]

Osborne and Ginnings, 1947
Osborne, N.S.; Ginnings, D.C., Measurements of heat of vaporization and heat capacity of a number of hydrocarbons, J. Res. NBS, 1947, 39, 453-477. [all data]

Nicolini and Laffitte, 1949
Nicolini, E.; Laffitte, P., Compt. Rend., 1949, 229, 757. [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]

Waddington and Douslin, 1947
Waddington, Guy; Douslin, Donald R., Experimental Vapor Heat Capacities and Heats of Vaporization of n-Hexane and 2,2-Dimethylbutane 1, J. Am. Chem. Soc., 1947, 69, 10, 2275-2279, https://doi.org/10.1021/ja01202a011 . [all data]

Kilpatrick and Pitzer, 1946
Kilpatrick, J.E.; Pitzer, K.S., The thermodynamics of 2,2-dimethylbutane, including the heat capacity, heats of transitions, fusion and vaporization and the entropy, J. Am. Chem. Soc., 1946, 68, 1066-1072. [all data]

Willingham, Taylor, et al., 1945
Willingham, C.B.; Taylor, W.J.; Pignocco, J.M.; Rossini, F.D., Vapor pressures and boiling points of some paraffin, alkylcyclopentane, alkylcyclohexane, and alkylbenzene hydrocarbons, J. RES. NATL. BUR. STAN., 1945, 35, 3, 219-17, https://doi.org/10.6028/jres.035.009 . [all data]

Williamham, Taylor, et al., 1945
Williamham, C.B.; Taylor, W.J.; Pignocco, J.M.; Rossini, F.D., Vapor Pressures and Boiling Points of Some Paraffin, Alkylcyclopentane, Alkylcyclohexane, and Alkylbenzene Hydrocarbons, J. Res. Natl. Bur. Stand. (U.S.), 1945, 35, 3, 219-244, https://doi.org/10.6028/jres.035.009 . [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]

Douslin and Huffman, 1946
Douslin, D.R.; Huffman, H.M., Low-temperature thermal data on the five isometric hexanes, J. Am. Chem. Soc., 1946, 68, 1704-1708. [all data]

Stull, 1937
Stull, D.R., A semi-micro calorimeter for measuring heat capacities at low temperatures, J. Am. Chem. Soc., 1937, 59, 2726-2733. [all data]


Notes

Go To: Top, Gas phase thermochemistry data, Phase change data, Mass spectrum (electron ionization), References