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Pentane, 2,2-dimethyl-

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Gas phase thermochemistry data

Go To: Top, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry 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 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
Deltafgas-206.2 ± 1.3kJ/molCcbProsen and Rossini, 1945ALS
Deltafgas-209.5kJ/molN/ADavies and Gilbert, 1941Value computed using «DELTA»fHliquid° value of -242.0±1.0 kj/mol from Davies and Gilbert, 1941 and «DELTA»vapH° value of 32.5 kj/mol from Prosen and Rossini, 1945.; DRB
Quantity Value Units Method Reference Comment
gas392.88J/mol*KN/AHuffman H.M., 1961GT

Constant pressure heat capacity of gas

Cp,gas (J/mol*K) Temperature (K) Reference Comment
116.86200.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. However, large uncertainties could be expected at high temperatures.; GT
153.93273.15
166.7 ± 0.4298.15
167.65300.
216.77400.
259.78500.
296.65600.
328.03700.
355.22800.
379.07900.
399.991000.
418.401100.
434.721200.
447.691300.
464.421400.
476.981500.

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
Deltafliquid-238.7 ± 1.3kJ/molCcbProsen and Rossini, 1945ALS
Deltafliquid-242. ± 1.kJ/molCcbDavies and Gilbert, 1941ALS
Quantity Value Units Method Reference Comment
Deltacliquid-4802.6 ± 1.3kJ/molCcbProsen and Rossini, 1945Corresponding «DELTA»fliquid = -238.6 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS
Deltacliquid-4798. ± 1.kJ/molCcbDavies and Gilbert, 1941Corresponding «DELTA»fliquid = -242.8 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS
Quantity Value Units Method Reference Comment
liquid300.29J/mol*KN/AHuffman, Gross, et al., 1961DH
liquid284.9J/mol*KN/AHuffman, Parks, et al., 1930Extrapolation below 90 K, 64.10 J/mol*K.; DH

Constant pressure heat capacity of liquid

Cp,liquid (J/mol*K) Temperature (K) Reference Comment
221.12298.15Huffman, Gross, et al., 1961T = 10 to 300 K.; DH
217.1294.1Huffman, Parks, et al., 1930T = 92 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
DH - Eugene S. Domalski and Elizabeth D. Hearing

Quantity Value Units Method Reference Comment
Tboil352.3 ± 0.3KAVGN/AAverage of 48 out of 53 values; Individual data points
Quantity Value Units Method Reference Comment
Tfus149. ± 2.KAVGN/AAverage of 20 out of 22 values; Individual data points
Quantity Value Units Method Reference Comment
Ttriple149.2 ± 0.9KAVGN/AAverage of 7 values; Individual data points
Quantity Value Units Method Reference Comment
Tc520.5 ± 0.5KN/ADaubert, 1996 
Tc520.44KN/AMcMicking and Kay, 1965Uncertainty assigned by TRC = 0.4 K; TRC
Tc520.85KN/AEdgar and Calingaert, 1929Uncertainty assigned by TRC = 0.5 K; measured by Keys and Kleinschmidt; TRC
Quantity Value Units Method Reference Comment
Pc27.7 ± 0.5barN/ADaubert, 1996 
Pc27.730barN/AMcMicking and Kay, 1965Uncertainty assigned by TRC = 0.4053 bar; TRC
Pc28.7763barN/AEdgar and Calingaert, 1929Uncertainty assigned by TRC = 0.5066 bar; measured by Keys and Kleinschmidt; TRC
Quantity Value Units Method Reference Comment
Vc0.416l/molN/ADaubert, 1996 
Quantity Value Units Method Reference Comment
rhoc2.41 ± 0.05mol/lN/ADaubert, 1996 
rhoc2.41mol/lN/AMcMicking and Kay, 1965Uncertainty assigned by TRC = 0.05 mol/l; TRC
Quantity Value Units Method Reference Comment
Deltavap32.56kJ/molN/AMajer and Svoboda, 1985 
Deltavap32.4 ± 0.1kJ/molCSvoboda, 1998AC
Deltavap32.4 ± 0.1kJ/molCOsborne and Ginnings, 1947AC
Deltavap32.2 ± 0.1kJ/molCOsborne and Ginnings, 1947AC
Deltavap32.42kJ/molCOsborne and Ginnings, 1947, 2ALS

Reduced pressure boiling point

Tboil (K) Pressure (bar) Reference Comment
351.20.991Aldrich Chemical Company Inc., 1990BS

Enthalpy of vaporization

DeltavapH (kJ/mol) Temperature (K) Method Reference Comment
29.23352.4N/AMajer and Svoboda, 1985 
31.8 ± 0.1308.CSvoboda, 1998AC
31.4 ± 0.1315.CSvoboda, 1998AC
31.0 ± 0.1323.CSvoboda, 1998AC
30.5 ± 0.1330.CSvoboda, 1998AC
30.1 ± 0.1338.CSvoboda, 1998AC
29.4 ± 0.1348.CSvoboda, 1998AC
28.8 ± 0.1358.CSvoboda, 1998AC
28.1 ± 0.1368.CSvoboda, 1998AC
33.2292.AStephenson and Malanowski, 1987Based on data from 277. - 354. K.; AC
30.1368.AStephenson and Malanowski, 1987Based on data from 353. - 483. K.; AC
32.8300.N/AForziati, Norris, et al., 1949Based on data from 285. - 353. K.; AC
32.6303.MMWillingham, Taylor, et al., 1945Based on data from 288. - 353. K.; AC

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
288.47 - 353.203.939991190.298-49.807Williamham, Taylor, et al., 1945

Enthalpy of fusion

DeltafusH (kJ/mol) Temperature (K) Reference Comment
5.824149.43Huffman, Gross, et al., 1961DH
5.86148.1Acree, 1991AC
5.862148.1Huffman, Parks, et al., 1930DH

Entropy of fusion

DeltafusS (J/mol*K) Temperature (K) Reference Comment
38.98149.43Huffman, Gross, et al., 1961DH
39.58148.1Huffman, 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

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

Hydrogen + 1-Pentene, 4,4-dimethyl- = Pentane, 2,2-dimethyl-

By formula: H2 + C7H14 = C7H16

Quantity Value Units Method Reference Comment
Deltar-122.6 ± 0.6kJ/molChydRogers and Dejroongruang, 1989liquid phase; solvent: Cyclohexane
Deltar-122.5 ± 0.42kJ/molChydDolliver, Gresham, et al., 1937gas phase; Reanalyzed by Cox and Pilcher, 1970, Original value = -123.56 ± 0.63 kJ/mol; At 355 °K

Hydrogen + 2-Pentene, 4,4-dimethyl-, (E)- = Pentane, 2,2-dimethyl-

By formula: H2 + C7H14 = C7H16

Quantity Value Units Method Reference Comment
Deltar-114.2 ± 0.4kJ/molChydRogers and Dejroongruang, 1989liquid phase; solvent: Cyclohexane
Deltar-111.kJ/molChydTurner, Nettleton, et al., 1958liquid phase; solvent: Acetic acid

Hydrogen + 2-Pentene, 4,4-dimethyl-, (Z)- = Pentane, 2,2-dimethyl-

By formula: H2 + C7H14 = C7H16

Quantity Value Units Method Reference Comment
Deltar-130.4 ± 0.4kJ/molChydRogers and Dejroongruang, 1989liquid phase; solvent: Cyclohexane
Deltar-129.kJ/molChydTurner, Nettleton, et al., 1958liquid phase; solvent: Acetic acid

Heptane = Pentane, 2,2-dimethyl-

By formula: C7H16 = C7H16

Quantity Value Units Method Reference Comment
Deltar-14.3 ± 1.2kJ/molCcbProsen and Rossini, 1941liquid phase; Heat of Isomerization
Deltar-18.6 ± 1.3kJ/molCcbProsen and Rossini, 1941gas phase; Heat of Isomerization

IR Spectrum

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

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 .


Mass spectrum (electron ionization)

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, IR Spectrum, 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.
NIST MS number 1042

All mass spectra in this site (plus many more) are available from the NIST/EPA/NIH Mass Spectral Library. Please see the following for information about the library and its accompanying search program.


References

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

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]

Huffman H.M., 1961
Huffman H.M., Low temperature thermodynamic properties of six isomeric heptanes, J. Phys. Chem., 1961, 65, 495-503. [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]

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]

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]

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]

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]

Svoboda, 1998
Svoboda, V., Enthalpies of vaporization, and the cohesive and internal energies of 2,2-dimethylpentane, 2,4-dimethylpentane, 2,2,3-trimethylpentane, 2,3,3-trimethylpentane, and 3-ethylpentane, The Journal of Chemical Thermodynamics, 1998, 30, 11, 1411-1417, https://doi.org/10.1006/jcht.1998.0414 . [all data]

Osborne and Ginnings, 1947
Osborne, Nathan S.; Ginnings, Defoe C., Measurements of heat of vaporization and heat capacity of a number of hydrocarbons, J. RES. NATL. BUR. STAN., 1947, 39, 5, 453-17, https://doi.org/10.6028/jres.039.031 . [all data]

Osborne and Ginnings, 1947, 2
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]

Aldrich Chemical Company Inc., 1990
Aldrich Chemical Company Inc., Catalog Handbook of Fine Chemicals, Aldrich Chemical Company, Inc., Milwaukee WI, 1990, 1. [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]

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]

Acree, 1991
Acree, William E., Thermodynamic properties of organic compounds: enthalpy of fusion and melting point temperature compilation, Thermochimica Acta, 1991, 189, 1, 37-56, https://doi.org/10.1016/0040-6031(91)87098-H . [all data]

Rogers and Dejroongruang, 1989
Rogers, D.W.; Dejroongruang, K., Enthalpies of hydrogenation of the dimethylpentenes, ethylpentenes, methylbutene, and trimethylbutene, J. Chem. Thermodyn., 1989, 21, 1115-1120. [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]

Cox and Pilcher, 1970
Cox, J.D.; Pilcher, G., Thermochemistry of Organic and Organometallic Compounds, Academic Press, New York, 1970, 1-636. [all data]

Turner, Nettleton, et al., 1958
Turner, R.B.; Nettleton, J.E.; Perelman, Heats of Hydrogenation. VI. Heats of hydrogenation of some substituted ethylenes, J. Am. Chem. Soc., 1958, 80, 1430-1433. [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

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