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Pentane, 3,3-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
DRB - Donald R. Burgess, Jr.
GT - Glushko Thermocenter, Russian Academy of Sciences, Moscow

Quantity Value Units Method Reference Comment
Deltafgas-201.5 ± 0.92kJ/molCcbProsen and Rossini, 1945ALS
Deltafgas-205.9kJ/molN/ADavies and Gilbert, 1941Value computed using «DELTA»fHliquid° value of -239.0±1.0 kj/mol from Davies and Gilbert, 1941 and «DELTA»vapH° value of 33.1 kj/mol from Prosen and Rossini, 1945.; DRB
Quantity Value Units Method Reference Comment
gas398.02J/mol*KN/AFinke H.L., 1976GT

Constant pressure heat capacity of gas

Cp,gas (J/mol*K) Temperature (K) Reference Comment
187.44 ± 0.37344.13Hossenlopp I.A., 1981GT
197.68 ± 0.40366.22
214.51 ± 0.43402.31
235.08 ± 0.47449.30
250.70 ± 0.50487.21

Constant pressure heat capacity of gas

Cp,gas (J/mol*K) Temperature (K) Reference Comment
113.72200.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
152.97273.15
165.8 ± 0.8298.15
166.69300.
215.35400.
258.45500.
295.81600.
327.61700.
355.22800.
379.49900.
400.411000.
419.241100.
435.551200.
451.871300.
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-234.6 ± 0.92kJ/molCcbProsen and Rossini, 1945ALS
Deltafliquid-239. ± 1.kJ/molCcbDavies and Gilbert, 1941ALS
Quantity Value Units Method Reference Comment
Deltacliquid-4806.70 ± 0.79kJ/molCcbProsen and Rossini, 1945Corresponding «DELTA»fliquid = -234.5 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS
Deltacliquid-4802. ± 1.kJ/molCcbDavies and Gilbert, 1941Corresponding «DELTA»fliquid = -239.1 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS
Quantity Value Units Method Reference Comment
liquid305.6J/mol*KN/AFinke, Messerly, et al., 1976DH
liquid293.3J/mol*KN/AHuffman, Parks, et al., 1930Extrapolation below 90 K, 60.67 J/mol*K.; DH

Constant pressure heat capacity of liquid

Cp,liquid (J/mol*K) Temperature (K) Reference Comment
214.8298.15Finke, Messerly, et al., 1976T = 10 to 400 K.; DH
211.7292.9Huffman, Parks, et al., 1930T = 92 to 293 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
Tboil359.2 ± 0.2KAVGN/AAverage of 34 out of 38 values; Individual data points
Quantity Value Units Method Reference Comment
Tfus138.1 ± 0.9KAVGN/AAverage of 25 values; Individual data points
Quantity Value Units Method Reference Comment
Ttriple138.75KN/AFinke, Messerly, et al., 1976, 2Crystal phase 1 phase; Uncertainty assigned by TRC = 0.1 K; TRC
Ttriple138.2KN/AFinke, Messerly, et al., 1976, 2Crystal phase 2 phase; Uncertainty assigned by TRC = 0.03 K; C2 is metastable at the melting point; TRC
Ttriple138.2KN/AHuffman, Parks, et al., 1930, 2Uncertainty assigned by TRC = 0.2 K; TRC
Quantity Value Units Method Reference Comment
Tc536.4 ± 0.5KN/ADaubert, 1996 
Tc536.3KN/AMajer and Svoboda, 1985 
Tc536.34KN/AMcMicking and Kay, 1965Uncertainty assigned by TRC = 0.4 K; TRC
Quantity Value Units Method Reference Comment
Pc29.5 ± 0.5barN/ADaubert, 1996 
Pc29.458barN/AMcMicking and Kay, 1965Uncertainty assigned by TRC = 0.4053 bar; TRC
Quantity Value Units Method Reference Comment
Vc0.414l/molN/ADaubert, 1996 
Quantity Value Units Method Reference Comment
rhoc2.42 ± 0.05mol/lN/ADaubert, 1996 
rhoc2.42mol/lN/AMcMicking and Kay, 1965Uncertainty assigned by TRC = 0.05 mol/l; TRC
Quantity Value Units Method Reference Comment
Deltavap33.15kJ/molN/AMajer and Svoboda, 1985 
Deltavap33.0 ± 0.1kJ/molCHossenlopp and Scott, 1981AC
Deltavap33.0kJ/molN/AReid, 1972AC
Deltavap33.0 ± 0.1kJ/molCOsborne and Ginnings, 1947AC
Deltavap33.02kJ/molCOsborne and Ginnings, 1947, 2ALS

Enthalpy of vaporization

DeltavapH (kJ/mol) Temperature (K) Method Reference Comment
29.62359.2N/AMajer and Svoboda, 1985 
34.8266.N/AStephenson and Malanowski, 1987Based on data from 213. - 281. K.; AC
33.6295.N/AStephenson and Malanowski, 1987Based on data from 280. - 360. K.; AC
33.3300.MMStephenson and Malanowski, 1987Based on data from 285. - 360. K. See also Willingham, Taylor, et al., 1945.; AC
33.2302.N/AForziati, Norris, et al., 1949Based on data from 287. - 360. K.; AC

Enthalpy of vaporization

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

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Temperature (K) A (kJ/mol) beta Tc (K) Reference Comment
298. - 359.47.530.2661536.3Majer and Svoboda, 1985 

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
286.63 - 360.113.955681230.986-47.568Forziati, Norris, et al., 1949, 2Coefficents calculated by NIST from author's data.

Enthalpy of fusion

DeltafusH (kJ/mol) Temperature (K) Reference Comment
7.07138.2Domalski and Hearing, 1996AC
7.067138.2Huffman, Parks, et al., 1930DH

Entropy of fusion

DeltafusS (J/mol*K) Temperature (K) Reference Comment
51.14138.2Huffman, Parks, et al., 1930DH

Enthalpy of phase transition

DeltaHtrs (kJ/mol) Temperature (K) Initial Phase Final Phase Reference Comment
0.7937132.7crystaline, IIcrystaline, IFinke, Messerly, et al., 1976DH
7.6425138.20crystaline, IIliquidFinke, Messerly, et al., 1976DH
6.8463138.75crystaline, IliquidFinke, Messerly, et al., 1976DH

Entropy of phase transition

DeltaStrs (J/mol*K) Temperature (K) Initial Phase Final Phase Reference Comment
5.98132.7crystaline, IIcrystaline, IFinke, Messerly, et al., 1976DH
55.30138.20crystaline, IIliquidFinke, Messerly, et al., 1976DH
49.34138.75crystaline, IliquidFinke, Messerly, et al., 1976DH

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

Heptane = Pentane, 3,3-dimethyl-

By formula: C7H16 = C7H16

Quantity Value Units Method Reference Comment
Deltar-10.2 ± 0.63kJ/molCcbProsen and Rossini, 1941liquid phase; Heat of Isomerization
Deltar-13.6 ± 0.88kJ/molCcbProsen and Rossini, 1941gas phase; Heat of Isomerization

Hydrogen + 1-Pentene, 3,3-dimethyl- = Pentane, 3,3-dimethyl-

By formula: H2 + C7H14 = C7H16

Quantity Value Units Method Reference Comment
Deltar-122.9 ± 1.0kJ/molChydRogers and Dejroongruang, 1989liquid phase; solvent: Cyclohexane

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 Sadtler Research Labs Under US-EPA Contract
State gas

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 19768

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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]

Finke H.L., 1976
Finke H.L., Low-temperature thermal quantities for five alkyl-substituted pentanes, J. Chem. Thermodyn., 1976, 8, 965-983. [all data]

Hossenlopp I.A., 1981
Hossenlopp I.A., Vapor heat capacities and enthalpies of vaporization of five alkane hydrocarbons, J. Chem. Thermodyn., 1981, 13, 415-421. [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]

Finke, Messerly, et al., 1976
Finke, H.L.; Messerly, J.F.; Douslin, D.R., Low-temperature thermal quantities for five alkyl-substituted pentanes, J. Chem. Thermodynam., 1976, 8, 965-983. [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]

Finke, Messerly, et al., 1976, 2
Finke, H.L.; Messerly, J.F.; Douslin, D.R., Low-Temp. Thermal Quantities for Five Alkyl-Substituted Pentanes, J. Chem. Thermodyn., 1976, 8, 965. [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]

Hossenlopp and Scott, 1981
Hossenlopp, I.A.; Scott, D.W., Vapor heat capacities and enthalpies of vaporization of five alkane hydrocarbons, J. Chem. Thermodyn., 1981, 13, 415-421. [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, 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]

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]

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]

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]

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]

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]


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