Pentane, 3-methyl-

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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
Δfgas-171.6 ± 0.96kJ/molCcbProsen and Rossini, 1945ALS
Quantity Value Units Method Reference Comment
gas382.88 ± 0.67J/mol*KN/AFinke H.L., 1973The entropy values S(323.8 K)=397.46 and S(336.5 K)=400.66 J/mol*K were calculated by [ Scott D.W., 1974] from the experimental data [ Finke H.L., 1973].; GT

Constant pressure heat capacity of gas

Cp,gas (J/mol*K) Temperature (K) Reference Comment
98.91200.Scott D.W., 1974, 2Recommended values were obtained from the consistent correlation scheme for alkanes [ Scott D.W., 1974, Scott D.W., 1974, 2]. This approach gives a better agreement with experimental data than the statistical thermodynamics calculation [ Pitzer K.S., 1946] (see also [ Waddington G., 1949]).; GT
129.83273.15
140.1 ± 0.4298.15
140.88300.
181.17400.
217.48500.
248.95600.
275.73700.
298.74800.
318.82900.
335.981000.
351.041100.
364.011200.
376.561300.
384.931400.
397.481500.

Constant pressure heat capacity of gas

Cp,gas (J/mol*K) Temperature (K) Reference Comment
154.31332.10Waddington G., 1949GT
168.41367.55
181.71402.35
194.64436.20
207.32471.15

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-202.0 ± 0.96kJ/molCcbProsen and Rossini, 1945ALS
Quantity Value Units Method Reference Comment
Δcliquid-4159.9 ± 0.88kJ/molCcbProsen and Rossini, 1945Corresponding Δfliquid = -201.9 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS
Quantity Value Units Method Reference Comment
liquid292.5J/mol*KN/AFinke and Messerly, 1973Thermodynamic properties calculated from a Debye function at 10 K.; DH

Constant pressure heat capacity of liquid

Cp,liquid (J/mol*K) Temperature (K) Reference Comment
191.16298.15Ohnishi, Fujihara, et al., 1989DH
190.99298.15`Benson and D'Arcy, 1986DH
190.86298.15Benson, D'Arcy, et al., 1984DH
190.77298.15Aicart, Kumaran, et al., 1983DH
190.77298.15Benson, D'Arcy, et al., 1983DH
187.1288.19Oguni, Watanabe, et al., 1982T = 80 to 370 K. Unsmoothed experimental datum. Heat capacity measured as a check of the calorimeter's performance.; DH
186.8298.95Czarnota, 1980DH
190.67298.15Finke and Messerly, 1973T = 10 to 330 K.; DH
187.36298.1Stull, 1937T = 90 to 320 K.; DH

Constant pressure heat capacity of solid

Cp,solid (J/mol*K) Temperature (K) Reference Comment
190.83298.15Douslin and Huffman, 1946T = 13 to 300 K.; 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
Tboil336.4 ± 0.4KAVGN/AAverage of 53 out of 57 values; Individual data points
Quantity Value Units Method Reference Comment
Tfus155.15KN/AHoog, Smittenberg, et al., 1937Uncertainty assigned by TRC = 2. K; TRC
Tfus155.15KN/ABruun and Hicks-Brunn, 1930Uncertainty assigned by TRC = 1. K; TRC
Quantity Value Units Method Reference Comment
Ttriple110.25KN/AFinke and Messerly, 1973, 2Uncertainty assigned by TRC = 0.006 K; by extrapolation of 1/f to 0; TRC
Quantity Value Units Method Reference Comment
Tc504. ± 4.KAVGN/AAverage of 8 values; Individual data points
Quantity Value Units Method Reference Comment
Pc31.1 ± 0.6barAVGN/AAverage of 6 values; Individual data points
Quantity Value Units Method Reference Comment
Vc0.368l/molN/ADaubert, 1996 
Quantity Value Units Method Reference Comment
ρc2.72 ± 0.02mol/lN/ADaubert, 1996 
ρc2.72mol/lN/AGenco, Teja, et al., 1980Uncertainty assigned by TRC = 0.06 mol/l; TRC
ρc2.73mol/lN/AKay, 1946Uncertainty assigned by TRC = 0.02 mol/l; by extrapolation of rectilinear diameter to Tc; TRC
Quantity Value Units Method Reference Comment
Δvap30.3 ± 0.2kJ/molAVGN/AAverage of 6 values; Individual data points

Enthalpy of vaporization

ΔvapH (kJ/mol) Temperature (K) Method Reference Comment
28.06336.4N/AMajer and Svoboda, 1985 
29.9331.N/ALoras, Aucejo, et al., 1999Based on data from 316. to 361. K.; AC
30.5308.AStephenson and Malanowski, 1987Based on data from 293. to 338. K.; AC
29.5 ± 0.1313.CMajer, Svoboda, et al., 1979AC
28.3 ± 0.1333.CMajer, Svoboda, et al., 1979AC
27.0 ± 0.1353.CMajer, Svoboda, et al., 1979AC
30.00 ± 0.008303.1CWaddington, Smith, et al., 1949ALS
30.0 ± 0.1303.CWaddington, Smith, et al., 1949AC
28.8 ± 0.1324.CWaddington, Smith, et al., 1949AC
28.1 ± 0.1336.CWaddington, Smith, et al., 1949AC
30.2303.MMWillingham, Taylor, et al., 1945Based on data from 288. to 337. K.; AC

Enthalpy of vaporization

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

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Temperature (K) 298. to 353.
A (kJ/mol) 45.24
α 0.
β 0.2703
Tc (K) 504.4
ReferenceMajer 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
288.44 to 337.233.973771152.368-46.021Williamham, Taylor, et al., 1945

Enthalpy of fusion

ΔfusH (kJ/mol) Temperature (K) Reference Comment
5.31110.3Domalski and Hearing, 1996AC

Enthalpy of phase transition

ΔHtrs (kJ/mol) Temperature (K) Initial Phase Final Phase Reference Comment
5.3032110.26crystaline, IliquidFinke and Messerly, 1973DH

Entropy of phase transition

ΔStrs (J/mol*K) Temperature (K) Initial Phase Final Phase Reference Comment
48.101110.26crystaline, IliquidFinke and Messerly, 1973DH

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:


Henry's Law 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: Rolf Sander

Henry's Law constant (water solution)

kH(T) = H exp(d(ln(kH))/d(1/T) ((1/T) - 1/(298.15 K)))
H = Henry's law constant for solubility in water at 298.15 K (mol/(kg*bar))
d(ln(kH))/d(1/T) = Temperature dependence constant (K)

H (mol/(kg*bar)) d(ln(kH))/d(1/T) (K) Method Reference Comment
0.00088 QN/A missing citation give several references for the Henry's law constants but don't assign them to specific species.
0.00059 LN/A 
0.00059 VN/A 

Gas phase ion energetics data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Henry's Law 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 as indicated in comments:
LL - Sharon G. Lias and Joel F. Liebman
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron

Ionization energy determinations

IE (eV) Method Reference Comment
10.04ESTLuo and Pacey, 1992LL
9.82EQLias, Ausloos, et al., 1976LLK
10.08PIWatanabe, Nakayama, et al., 1962RDSH

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
C4H8+10.58 ± 0.015C2H6PISteiner, Giese, et al., 1961RDSH
C4H9+10.95 ± 0.07C2H5PISteiner, Giese, et al., 1961RDSH
C5H10+10.70 ± 0.055CH4PISteiner, Giese, et al., 1961RDSH
C5H11+10.86 ± 0.085CH3PISteiner, Giese, et al., 1961RDSH

Mass spectrum (electron ionization)

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Henry's Law data, Gas phase ion energetics data, 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.
Origin Japan AIST/NIMC Database- Spectrum MS-NW-1215
NIST MS number 227827

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References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Henry's Law data, Gas phase ion energetics data, 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]

Finke H.L., 1973
Finke H.L., 3-Methylpentane and 3-methylheptane: low-temperature thermodynamic properties, J. Chem. Thermodyn., 1973, 5, 247-257. [all data]

Scott D.W., 1974
Scott D.W., Correlation of the chemical thermodynamic properties of alkane hydrocarbons, J. Chem. Phys., 1974, 60, 3144-3165. [all data]

Scott D.W., 1974, 2
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]

Pitzer K.S., 1946
Pitzer K.S., The entropies and related properties of branched paraffin hydrocarbons, Chem. Rev., 1946, 39, 435-447. [all data]

Waddington G., 1949
Waddington G., Experimental vapor heat capacities and heats of vaporization of 2-methylpentane, 3-methylpentane, and 2,3-dimethylbutane, J. Am. Chem. Soc., 1949, 71, 3902-3906. [all data]

Finke and Messerly, 1973
Finke, H.L.; Messerly, J.F., 3-Methylpentane and 3-methylheptane: low-temperature thermodynamic properties, J. Chem. Thermodynam., 1973, 5, 247-257. [all data]

Ohnishi, Fujihara, et al., 1989
Ohnishi, K.; Fujihara, I.; Murakami, S., Thermodynamic properties of decalins mixed with hexane isomers at 298.15K. 1. Excess enthalpies and excess isobaric heat capacities, Fluid Phase Equilib., 1989, 46, 59-72. [all data]

Benson and D'Arcy, 1986
Benson, G.C.; D'Arcy, P.J., Heat capacities of binary mixtures of n-octane with each of the hexane isomers at 298.15 K, Can. J. Chem., 1986, 64, 2139-2141. [all data]

Benson, D'Arcy, et al., 1984
Benson, G.C.; D'Arcy, P.J.; Kumaran, M.K., Heat capacities of binary mixtures of n-heptane with hexane isomers, Thermochim. Acta, 1984, 75, 353-360. [all data]

Aicart, Kumaran, et al., 1983
Aicart, E.; Kumaran, M.K.; Halpin, C.J.; Benson, G.C., Ultrasonic speeds and isentropic compressibilities of 2-methylpentan-1-ol with hexane isomers at 298.15 K, J. Chem. Thermodynam., 1983, 15, 1189-1197. [all data]

Benson, D'Arcy, et al., 1983
Benson, G.C.; D'Arcy, P.J.; Sugamori, M.E., Heat capacities of binary mixtures of 1-hexanol with hexane isomers at 298.15 K, Thermochim. Acta, 1983, 71, 161-166. [all data]

Oguni, Watanabe, et al., 1982
Oguni, M.; Watanabe, K.; Matsuo, T.; Suga, H.; Seki, S., Construction of an adiabatic calorimeter workable under constant high pressure, Bull. Chem. Soc. Japan, 1982, 55, 77-84. [all data]

Czarnota, 1980
Czarnota, I., Heat capacity of 3-methylpentane at high pressures, Bull. Acad. Pol. Sci., Ser. Sci. Chim., 1980, 28(9-10), 651-659. [all data]

Stull, 1937
Stull, D.R., A semi-micro calorimeter for measuring heat capacities at low temperatures, J. Am. Chem. Soc., 1937, 59, 2726-2733. [all data]

Douslin and Huffman, 1946
Douslin, D.R.; Huffman, H.M., Low-temperature thermal data on the five isometric hexanes, J. Am. Chem. Soc., 1946, 68, 1704-1708. [all data]

Hoog, Smittenberg, et al., 1937
Hoog, H.; Smittenberg, J.; Visser, G.H., Composition of the Primary Polymerization Prod. of Propene and Butenes in IIe Congr. Mondial Pet. 2, Sect. 2, Phys. Chim. Raffin- age, p 489, 1937. [all data]

Bruun and Hicks-Brunn, 1930
Bruun, J.H.; Hicks-Brunn, M.M., The Isolation of the Isomers of Hexane from Petroleum, J. Res. Natl. Bur. Stand. (U. S.), 1930, 5, 933. [all data]

Finke and Messerly, 1973, 2
Finke, H.L.; Messerly, J.F., 3-Methylpentane and 3-Methylheptane: Low-temperature Thermo. Properties properties, J. Chem. Thermodyn., 1973, 5, 247. [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]

Genco, Teja, et al., 1980
Genco, J.M.; Teja, A.S.; Kay, W.B., Study of the critical and azeotropic behavior of binary mixtures I critical states of perfluoromethylcyclohexane + isomeric hexane systems, J. Chem. Eng. Data, 1980, 25, 350. [all data]

Kay, 1946
Kay, W.B., The Vapor Pressures and Saturated Liquid and Vapor Densities of the Isomeric Hexanes, J. Am. Chem. Soc., 1946, 68, 1336. [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]

Loras, Aucejo, et al., 1999
Loras, Sonia; Aucejo, Antonio; Muñoz, Rosa, Vapor--liquid equilibria in the systems 3-methylpentane+methyl 1,1-dimethylethyl ether and 3-methylpentane+methyl 1,1-dimethylpropyl ether at 101.3 kPa, Fluid Phase Equilibria, 1999, 156, 1-2, 185-195, https://doi.org/10.1016/S0378-3812(99)00028-X . [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]

Majer, Svoboda, et al., 1979
Majer, Vladimír; Svoboda, Václav; Hála, Slavoj; Pick, Jirí, Temperature dependence of heats of vaporization of saturated hydrocarbons C5-C8; Experimental data and an estimation method, Collect. Czech. Chem. Commun., 1979, 44, 3, 637-651, https://doi.org/10.1135/cccc19790637 . [all data]

Waddington, Smith, et al., 1949
Waddington, G.; Smith, J.C.; Scott, D.W.; Huffman, H.M., Experimental vapor heat capacities and heats of vaporization of 2-methylpentane, 3-methylpentane and 2,3-dimethylbutane, J. Am. Chem. Soc., 1949, 71, 3902-3906. [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]

Luo and Pacey, 1992
Luo, Y.-R.; Pacey, P.D., Effects of alkyl substitution on ionization energies of alkanes and haloalkanes and on heats of formation of their molecular cations. Part 2. Alkanes and chloro-, bromo- and iodoalkanes, Int. J. Mass Spectrom. Ion Processes, 1992, 112, 63. [all data]

Lias, Ausloos, et al., 1976
Lias, S.G.; Ausloos, P.; Horvath, Z., Charge transfer reactions in alkane and cycloalkane systems. Estimated ionization potentials, Int. J. Chem. Kinet., 1976, 8, 725. [all data]

Watanabe, Nakayama, et al., 1962
Watanabe, K.; Nakayama, T.; Mottl, J., Ionization potentials of some molecules, J. Quant. Spectry. Radiative Transfer, 1962, 2, 369. [all data]

Steiner, Giese, et al., 1961
Steiner, B.; Giese, C.F.; Inghram, M.G., Photoionization of alkanes. Dissociation of excited molecular ions, J. Chem. Phys., 1961, 34, 189. [all data]


Notes

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Henry's Law data, Gas phase ion energetics data, Mass spectrum (electron ionization), References