Pentane, 3-ethyl-3-methyl-

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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: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

Quantity Value Units Method Reference Comment
Δfliquid-253.0 ± 1.3kJ/molCcbProsen and Rossini, 1945 
Quantity Value Units Method Reference Comment
Δcliquid-5467.7 ± 1.1kJ/molCcbProsen and Rossini, 1945Corresponding Δfliquid = -252.9 kJ/mol (simple calculation by NIST; no Washburn corrections)

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

Quantity Value Units Method Reference Comment
Tboil391.5 ± 0.3KAVGN/AAverage of 17 values; Individual data points
Quantity Value Units Method Reference Comment
Tfus182.5 ± 0.8KAVGN/AAverage of 12 values; Individual data points
Quantity Value Units Method Reference Comment
Tc576.5 ± 0.5KN/ADaubert, 1996 
Tc576.5KN/AMajer and Svoboda, 1985 
Tc576.51KN/AMcMicking and Kay, 1965Uncertainty assigned by TRC = 0.4 K; TRC
Quantity Value Units Method Reference Comment
Pc28.1 ± 0.4barN/ADaubert, 1996 
Pc28.073barN/AMcMicking and Kay, 1965Uncertainty assigned by TRC = 0.4053 bar; TRC
Quantity Value Units Method Reference Comment
Vc0.455l/molN/ADaubert, 1996 
Quantity Value Units Method Reference Comment
ρc2.20 ± 0.04mol/lN/ADaubert, 1996 
ρc2.20mol/lN/AMcMicking and Kay, 1965Uncertainty assigned by TRC = 0.04 mol/l; TRC
Quantity Value Units Method Reference Comment
Δvap38.05kJ/molN/AMajer and Svoboda, 1985 
Δvap38.0kJ/molN/AReid, 1972AC
Δvap38.0 ± 0.1kJ/molCOsborne and Ginnings, 1947AC
Δvap37.98kJ/molCOsborne and Ginnings, 1947, 2ALS

Enthalpy of vaporization

ΔvapH (kJ/mol) Temperature (K) Method Reference Comment
32.78391.4N/AMajer and Svoboda, 1985 
36.9327.A,MMStephenson and Malanowski, 1987Based on data from 312. to 393. K. See also Willingham, Taylor, et al., 1945.; AC
40.2264.N/AStull, 1947Based on data from 249. to 391. 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) β Tc (K) Reference Comment
298. to 391.52.460.2592576.5Majer 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
249.3 to 391.54.048171380.13-49.963Stull, 1947Coefficents calculated by NIST from author's data.

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

Octane = Pentane, 3-ethyl-3-methyl-

By formula: C8H18 = C8H18

Quantity Value Units Method Reference Comment
Δr-3.1 ± 0.88kJ/molCisoProsen and Rossini, 1945, 2liquid phase; Calculated from ΔHc

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, 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]

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]

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]

Stull, 1947
Stull, Daniel R., Vapor Pressure of Pure Substances. Organic and Inorganic Compounds, Ind. Eng. Chem., 1947, 39, 4, 517-540, https://doi.org/10.1021/ie50448a022 . [all data]

Prosen and Rossini, 1945, 2
Prosen, E.J.; Rossini, F.D., Heats of isomerization of the 18 octanes, J. Res. NBS, 1945, 34, 163-174. [all data]


Notes

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