Butane, 2,2,3-trimethyl-

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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
DRB - Donald R. Burgess, Jr.
GT - Glushko Thermocenter, Russian Academy of Sciences, Moscow

Quantity Value Units Method Reference Comment
Δfgas-48.96 ± 0.27kcal/molCcbProsen and Rossini, 1945ALS
Δfgas-49.21kcal/molN/ADavies and Gilbert, 1941Value computed using ΔfHliquid° value of -238.0±1.0 kj/mol from Davies and Gilbert, 1941 and ΔvapH° value of 32.1 kj/mol from Prosen and Rossini, 1945.; DRB

Constant pressure heat capacity of gas

Cp,gas (cal/mol*K) Temperature (K) Reference Comment
26.640200.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 good agreement with experimental data available for alkanes. Results of statistical thermodynamics calculation for 2,2,3-trimethylbutane [ Scott D.W., 1953] also agree well with experimental data at low temperatures. However, the values of S and Cp at 1500 K are 15 and 33 J/mol*K below than those given by [ Scott D.W., 1974].; GT
35.961273.15
39.02 ± 0.1298.15
39.250300.
50.870400.
61.200500.
70.201600.
78.000700.
84.900800.
90.999900.
96.3001000.
101.001100.
105.201200.
109.001300.
112.001400.
115.001500.

Constant pressure heat capacity of gas

Cp,gas (cal/mol*K) Temperature (K) Reference Comment
42.739 ± 0.043328.80Waddington G., 1947GT
45.091 ± 0.045348.85
47.390 ± 0.048369.20
50.920 ± 0.050400.40
54.541 ± 0.055434.30
57.359 ± 0.057461.80

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-56.63 ± 0.27kcal/molCcbProsen and Rossini, 1945ALS
Δfliquid-56.8 ± 0.3kcal/molCcbDavies and Gilbert, 1941ALS
Quantity Value Units Method Reference Comment
Δcliquid-1148.18 ± 0.12kcal/molCmCoops, Mulder, et al., 1946Reanalyzed by Cox and Pilcher, 1970, Original value = -1147.72 ± 0.07 kcal/mol; Corresponding Δfliquid = -56.70 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS
Δcliquid-1148.27 ± 0.25kcal/molCcbProsen and Rossini, 1945Corresponding Δfliquid = -56.61 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS
Δcliquid-1148.0 ± 0.3kcal/molCcbDavies and Gilbert, 1941Corresponding Δfliquid = -56.91 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS
Quantity Value Units Method Reference Comment
liquid69.849cal/mol*KN/AHuffman, Gross, et al., 1961DH
liquid6.479cal/mol*KN/AHuffman, Parks, et al., 1930Extrapolation below 90 K, 14.0 cal mol-1 K-1.; DH

Constant pressure heat capacity of liquid

Cp,liquid (cal/mol*K) Temperature (K) Reference Comment
51.030298.15Huffman, Gross, et al., 1961T = 10 to 300 K.; DH
49.81293.9Huffman, Parks, et al., 1930T = 89 to 294 K. Value is unsmoothed experimental datum.; DH

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
Tboil354.1 ± 0.2KAVGN/AAverage of 35 out of 37 values; Individual data points
Quantity Value Units Method Reference Comment
Tfus248. ± 1.KAVGN/AAverage of 17 out of 18 values; Individual data points
Quantity Value Units Method Reference Comment
Ttriple248.56KN/AHuffman, Gross, et al., 1961Crystal phase 1 phase; Uncertainty assigned by TRC = 0.07 K; solid solution assumed for impurities in extrapolation to the triple point; TRC
Ttriple248.480KN/AWaddington, 1952Uncertainty assigned by TRC = 0.05 K; TRC
Ttriple248.530KN/AWaddington, 1952Uncertainty assigned by TRC = 0.03 K; TRC
Ttriple248.530KN/AHuffman, 1948Uncertainty assigned by TRC = 0.05 K; TRC
Ttriple247.7KN/AHuffman, Parks, et al., 1930, 2Crystal phase 1 phase; Uncertainty assigned by TRC = 0.2 K; TRC
Quantity Value Units Method Reference Comment
Tc531.1 ± 0.3KN/ADaubert, 1996 
Tc531.1KN/AMajer and Svoboda, 1985 
Tc531.11KN/AMcMicking and Kay, 1965Uncertainty assigned by TRC = 0.4 K; TRC
Tc531.45KN/AEdgar and Calingaert, 1929Uncertainty assigned by TRC = 0.5 K; measured by Keys and Kleinschmidt; TRC
Quantity Value Units Method Reference Comment
Pc29.1 ± 0.5atmN/ADaubert, 1996 
Pc29.146atmN/AMcMicking and Kay, 1965Uncertainty assigned by TRC = 0.4000 atm; TRC
Pc29.7500atmN/AEdgar and Calingaert, 1929Uncertainty assigned by TRC = 0.5000 atm; measured by Keys and Kleinschmidt; TRC
Quantity Value Units Method Reference Comment
Vc0.398l/molN/ADaubert, 1996 
Quantity Value Units Method Reference Comment
ρc2.51 ± 0.05mol/lN/ADaubert, 1996 
ρc2.51mol/lN/AMcMicking and Kay, 1965Uncertainty assigned by TRC = 0.05 mol/l; TRC
Quantity Value Units Method Reference Comment
Δvap7.694kcal/molN/AMajer and Svoboda, 1985 
Δvap7.6kcal/molN/AReid, 1972AC
Δvap7.658kcal/molCOsborne and Ginnings, 1947ALS

Enthalpy of vaporization

ΔvapH (kcal/mol) Temperature (K) Method Reference Comment
6.91354.N/AMajer and Svoboda, 1985 
7.74299.AStephenson and Malanowski, 1987Based on data from 284. to 355. K.; AC
7.15368.AStephenson and Malanowski, 1987Based on data from 353. to 483. K.; AC
7.72301.N/AForziati, Norris, et al., 1949Based on data from 286. to 355. K.; AC
7.46 ± 0.02314.CWaddington, Todd, et al., 1947AC
7.62311.EBSmith, 1941Based on data from 296. to 378. 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
298. to 353.11.180.2726531.1Majer 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
285.70 to 354.923.91651203.362-46.776Forziati, Norris, et al., 1949, 2Coefficents calculated by NIST from author's data.

Enthalpy of fusion

ΔfusH (kcal/mol) Temperature (K) Reference Comment
0.53247.7Domalski and Hearing, 1996AC

Entropy of fusion

ΔfusS (cal/mol*K) Temperature (K) Reference Comment
4.694121.Domalski and Hearing, 1996CAL
2.12247.7

Enthalpy of phase transition

ΔHtrs (kcal/mol) Temperature (K) Initial Phase Final Phase Reference Comment
0.5359121.4crystaline, IIcrystaline, IHuffman, Gross, et al., 1961DH
0.5681121.0crystaline, IIcrystaline, IHuffman, Parks, et al., 1930Hump in heat capacity curve at about 105 K, with excess enthalpy of 243 J/mol.; DH
0.5261247.7crystaline, IliquidHuffman, Parks, et al., 1930DH

Entropy of phase transition

ΔStrs (cal/mol*K) Temperature (K) Initial Phase Final Phase Reference Comment
4.414121.4crystaline, IIcrystaline, IHuffman, Gross, et al., 1961DH
4.694121.0crystaline, IIcrystaline, IHuffman, Parks, et al., 1930Hump; DH
2.12247.7crystaline, IliquidHuffman, Parks, et al., 1930DH

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:


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

Heptane = Butane, 2,2,3-trimethyl-

By formula: C7H16 = C7H16

Quantity Value Units Method Reference Comment
Δr-3.00 ± 0.22kcal/molCcbProsen and Rossini, 1941liquid phase; Heat of Isomerization
Δr-4.17 ± 0.27kcal/molCcbProsen and Rossini, 1941gas phase; Heat of Isomerization

IR Spectrum

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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

Gas Phase Spectrum

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IR spectrum
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Additional Data

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Owner NIST Standard Reference Data Program
Collection (C) 2018 copyright by the U.S. Secretary of Commerce
on behalf of the United States of America. All rights reserved.
Origin NIST Mass Spectrometry Data Center
State gas
Instrument HP-GC/MS/IRD

This IR spectrum is from the NIST/EPA Gas-Phase Infrared Database .


References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, IR Spectrum, 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]

Davies and Gilbert, 1941
Davies, G.F.; Gilbert, E.C., Heats of combustion and formation of the nine isomeric heptanes in the liquid state, J. Am. Chem. Soc., 1941, 63, 2730-2732. [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]

Scott D.W., 1953
Scott D.W., Thermodynamic functions of 2,2,3-trimethylbutane, J. Am. Chem. Soc., 1953, 75, 2006-2007. [all data]

Waddington G., 1947
Waddington G., An improved flow calorimeter. Experimental vapor heat capacities and heats of vaporization of n-heptane and 2,2,3-trimethylbutane, J. Am. Chem. Soc., 1947, 69, 22-30. [all data]

Coops, Mulder, et al., 1946
Coops, J.; Mulder, D.; Dienske, J.W.; Smittenberg, J., The heats of combustion of a number of hydrocarbons, Rec. Trav. Chim. Pays/Bas, 1946, 65, 128. [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]

Huffman, Gross, et al., 1961
Huffman, H.M.; Gross, M.E.; Scott, D.W.; McCullough, I.P., Low temperature thermodynamic properties of six isomeric heptanes, J. Phys. Chem., 1961, 65, 495-503. [all data]

Huffman, Parks, et al., 1930
Huffman, H.M.; Parks, G.S.; Thomas, S.B., Thermal data on organic compounds. VIII. The heat capacities, entropies and free energies of the isomeric heptanes, J. Am. Chem. Soc., 1930, 52, 3241-3251. [all data]

Waddington, 1952
Waddington, G., Personal Commun., U. S. Bur. Mines, Bartlesville, OK, March 20, 1952. [all data]

Huffman, 1948
Huffman, H.M., Personal Commun., U. S. Bur. Mines, Bartlesville, OK, 1948. [all data]

Huffman, Parks, et al., 1930, 2
Huffman, H.M.; Parks, G.S.; Thomas, S.B., Thermal Data on Organic Compounds. VII The Heat Capacities, Entropies and Free Energies of the Isomeric Heptanes, J. Am. Chem. Soc., 1930, 52, 3241. [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]

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]

McMicking and Kay, 1965
McMicking, J.H.; Kay, W.B., Vapor Pressures and Saturated Liquid and Vapor Densities of The Isomeric Heptanes and Isomeric Octanes, Proc., Am. Pet. Inst., Sect. 3, 1965, 45, 75-90. [all data]

Edgar and Calingaert, 1929
Edgar, G.; Calingaert, G., Preparation and Properties of the Isomeric Heptanes II. Physical Prop. properties, J. Am. Chem. Soc., 1929, 51, 1540. [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]

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]

Forziati, Norris, et al., 1949
Forziati, Alphonse F.; Norris, William R.; Rossini, Frederick D., Vapor pressures and boiling points of sixty API-NBS hydrocarbons, J. RES. NATL. BUR. STAN., 1949, 43, 6, 555-17, https://doi.org/10.6028/jres.043.050 . [all data]

Waddington, Todd, et al., 1947
Waddington, Guy; Todd, Samuel S.; Huffman, Hugh M., An Improved Flow Calorimeter. Experimental Vapor Heat Capacities and Heats of Vaporization of n-Heptane and 2,2,3-Trimethylbutane 1, J. Am. Chem. Soc., 1947, 69, 1, 22-30, https://doi.org/10.1021/ja01193a007 . [all data]

Smith, 1941
Smith, E.R., Boiling points of benzene, 2,2,3-trimethylbutane, 3-ethylpentane, and 2,2,4,4-tetramethylpentane within the range 100 to 1,500 millimeters of mercury, J. RES. NATL. BUR. STAN., 1941, 26, 2, 129-17, https://doi.org/10.6028/jres.026.004 . [all data]

Forziati, Norris, et al., 1949, 2
Forziati, A.F.; Norris, W.R.; Rossini, F.D., Vapor Pressures and Boiling Points of Sixty API-NBS Hydrocarbons, J. Res. Natl. Bur. Stand. (U.S.), 1949, 43, 6, 555-563, https://doi.org/10.6028/jres.043.050 . [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]

Prosen and Rossini, 1941
Prosen, E.J.R.; Rossini, F.D., Heats of isomerization of the nine heptanes, J. Res. NBS, 1941, 27, 519-528. [all data]


Notes

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