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Pentane, 2,3,4-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
GT - Glushko Thermocenter, Russian Academy of Sciences, Moscow

Quantity Value Units Method Reference Comment
Deltafgas-51.97 ± 0.40kcal/molCcbProsen and Rossini, 1945ALS
Quantity Value Units Method Reference Comment
gas102.10 ± 0.30cal/mol*KN/APitzer K.S., 1941GT

Constant pressure heat capacity of gas

Cp,gas (cal/mol*K) Temperature (K) Reference Comment
55.81 ± 0.11373.15Hossenlopp I.A., 1981Please also see Pitzer K.S., 1941, Barrow G.M., 1951.; GT
58.91 ± 0.12398.15
59.300402.8
60.10 ± 0.60417.0
61.79 ± 0.12423.15
64.78 ± 0.13448.15
66.200463.6
67.65 ± 0.14473.15
70.26 ± 0.14498.15
72.500521.6
72.89 ± 0.15523.15

Constant pressure heat capacity of gas

Cp,gas (cal/mol*K) Temperature (K) Reference Comment
29.560200.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
42.110273.15
45.8 ± 0.1298.15
46.061300.
59.199400.
70.370500.
79.900600.
88.200700.
95.301800.
101.50900.
106.901000.
111.701100.
115.801200.
120.001300.
123.001400.
126.001500.

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-60.99 ± 0.40kcal/molCcbProsen and Rossini, 1945ALS
Quantity Value Units Method Reference Comment
Deltacliquid-1306.28 ± 0.38kcal/molCcbProsen and Rossini, 1945Corresponding «DELTA»fliquid = -60.96 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS
Quantity Value Units Method Reference Comment
liquid78.709cal/mol*KN/APitzer and Scott, 1941DH

Constant pressure heat capacity of liquid

Cp,liquid (cal/mol*K) Temperature (K) Reference Comment
59.111298.15Osborne and Ginnings, 1947T = 278 to 318 K.; DH
58.850293.79Pitzer and Scott, 1941T = 14 to 325 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
Tboil386.8 ± 0.3KAVGN/AAverage of 18 values; Individual data points
Quantity Value Units Method Reference Comment
Tfus163.8 ± 0.4KAVGN/AAverage of 10 out of 11 values; Individual data points
Quantity Value Units Method Reference Comment
Ttriple163.63KN/APitzer and Scott, 1941, 2Uncertainty assigned by TRC = 0.12 K; measured in calorimeter, extrap. to 1/F=0; TRC
Quantity Value Units Method Reference Comment
Tc566.4 ± 0.5KN/ADaubert, 1996 
Tc566.3KN/AMajer and Svoboda, 1985 
Tc566.34KN/AMcMicking and Kay, 1965Uncertainty assigned by TRC = 0.5 K; TRC
Quantity Value Units Method Reference Comment
Pc26.9 ± 0.4atmN/ADaubert, 1996 
Pc26.941atmN/AMcMicking and Kay, 1965Uncertainty assigned by TRC = 0.4000 atm; TRC
Quantity Value Units Method Reference Comment
Vc0.460l/molN/ADaubert, 1996 
Quantity Value Units Method Reference Comment
rhoc2.17 ± 0.04mol/lN/ADaubert, 1996 
rhoc2.17mol/lN/AMcMicking and Kay, 1965Uncertainty assigned by TRC = 0.04 mol/l; TRC
Quantity Value Units Method Reference Comment
Deltavap9.039kcal/molN/AMajer and Svoboda, 1985 
Deltavap9.01 ± 0.02kcal/molCHossenlopp and Scott, 1981AC
Deltavap9.01kcal/molN/AReid, 1972AC
Deltavap9.01 ± 0.02kcal/molCOsborne and Ginnings, 1947, 2AC
Deltavap9.011kcal/molCOsborne and Ginnings, 1947ALS

Enthalpy of vaporization

DeltavapH (kcal/mol) Temperature (K) Method Reference Comment
7.734386.6N/AMajer and Svoboda, 1985 
9.01303.AStephenson and Malanowski, 1987Based on data from 288. - 400. K.; AC
9.35274.AStephenson and Malanowski, 1987Based on data from 223. - 289. K.; AC
9.87238.IP,EBOsborn and Douslin, 1974Based on data from 223. - 426. K.; AC
9.51263.IPOsborn and Douslin, 1974Based on data from 223. - 278. K.; AC
8.77325.MMWillingham, Taylor, et al., 1945Based on data from 310. - 388. 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) beta Tc (K) Reference Comment
298. - 414.12.840.2772566.3Majer 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
222.83 - 426.324.150601420.71-44.618Osborn and Douslin, 1974Coefficents calculated by NIST from author's data.
309.72 - 387.533.973151315.084-55.624Williamham, Taylor, et al., 1945 

Enthalpy of fusion

DeltafusH (kcal/mol) Temperature (K) Reference Comment
2.215163.63Pitzer and Scott, 1941DH
2.22163.6Domalski and Hearing, 1996AC

Entropy of fusion

DeltafusS (cal/mol*K) Temperature (K) Reference Comment
13.54163.63Pitzer and Scott, 1941DH

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

Octane = Pentane, 2,3,4-trimethyl-

By formula: C8H18 = C8H18

Quantity Value Units Method Reference Comment
Deltar-1.25 ± 0.32kcal/molCisoProsen and Rossini, 1945, 2liquid phase; Calculated from «DELTA»Hc

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

View image of digitized spectrum (can be printed in landscape orientation).

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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 NIST Mass Spectrometry Data Center, 1990.
NIST MS number 114222

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]

Pitzer K.S., 1941
Pitzer K.S., The thermodynamics of branched-chain paraffins. The heat capacity, heat of fusion and vaporization and entropy of 2,3,4-trimethylpentane, J. Am. Chem. Soc., 1941, 63, 2419-2422. [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]

Barrow G.M., 1951
Barrow G.M., Experimental vapor heat capacities and heats of vaporization of seven octanes, J. Am. Chem. Soc., 1951, 73, 1824-1826. [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]

Pitzer and Scott, 1941
Pitzer, K.S.; Scott, D.W., The thermodynamics of branched-chain paraffins. The heat capacity, heat of fusion and vaporization, and entropy of 2,3,4-trimethylpentane, J. Am. Chem. Soc., 1941, 63, 2419-2422. [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]

Pitzer and Scott, 1941, 2
Pitzer, K.S.; Scott, D.W., The Thermodynamics of Branched-Chain Paraffins. The HEat Capacity, Heat of Fusion and Vaporization, and Entropy of 2,3,4-Trimethylpentane, J. Am. Chem. Soc., 1941, 63, 2419-22. [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, 2
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]

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]

Osborn and Douslin, 1974
Osborn, Ann G.; Douslin, Donald R., Vapor-pressure relations for 15 hydrocarbons, J. Chem. Eng. Data, 1974, 19, 2, 114-117, https://doi.org/10.1021/je60061a022 . [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]

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

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