Heptane, 2-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-215.5 ± 1.3kJ/molCcbProsen and Rossini, 1945ALS
Quantity Value Units Method Reference Comment
gas459.49 ± 0.88J/mol*KN/AMesserly J.F., 1971GT

Constant pressure heat capacity of gas

Cp,gas (J/mol*K) Temperature (K) Reference Comment
186.13298.15Colgate S.O., 1990GT
202.07323.15
230.06373.15
248.37408.15
265.52448.15

Constant pressure heat capacity of gas

Cp,gas (J/mol*K) Temperature (K) Reference Comment
135.65200.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
173.89273.15
187.2 ± 0.2298.15
188.20300.
241.25400.
288.78500.
329.28600.
363.17700.
391.62800.
416.31900.
436.811000.
454.801100.
470.701200.
485.341300.
497.901400.
510.451500.

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-255.2 ± 1.3kJ/molCcbProsen and Rossini, 1945ALS
Quantity Value Units Method Reference Comment
Δcliquid-5465.5 ± 1.2kJ/molCcbProsen and Rossini, 1945Corresponding Δfliquid = -255.1 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS
Δcliquid-5447.1kJ/molCcbFajans, 1920Corresponding Δfliquid = -273. kJ/mol (simple calculation by NIST; no Washburn corrections); ALS
Δcliquid-5274.6kJ/molCcbRichards and Jesse, 1910At 293 K; Corresponding Δfliquid = -446.0 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS
Quantity Value Units Method Reference Comment
liquid356.39J/mol*KN/AMesserly and Finke, 1971DH

Constant pressure heat capacity of liquid

Cp,liquid (J/mol*K) Temperature (K) Reference Comment
252.00298.15Messerly and Finke, 1971T = 11 to 370 K.; DH
251.58298.15Osborne and Ginnings, 1947T = 283 to 318 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
Tboil390.7 ± 0.8KAVGN/AAverage of 37 out of 38 values; Individual data points
Quantity Value Units Method Reference Comment
Tfus163. ± 2.KAVGN/AAverage of 14 values; Individual data points
Quantity Value Units Method Reference Comment
Ttriple160. ± 9.KAVGN/AAverage of 10 values; Individual data points
Quantity Value Units Method Reference Comment
Tc559.7 ± 0.1KN/ADaubert, 1996 
Tc559.7KN/AAbara, Jennings, et al., 1988Uncertainty assigned by TRC = 0.2 K; TRC
Tc559.6KN/AMajer and Svoboda, 1985 
Tc559.56KN/AMcMicking and Kay, 1965Uncertainty assigned by TRC = 0.4 K; TRC
Tc559.57KN/AAmbrose, Cox, et al., 1960Uncertainty assigned by TRC = 0.2 K; Visual, PRT, IPTS-48; TRC
Quantity Value Units Method Reference Comment
Pc25.0 ± 0.2barN/ADaubert, 1996 
Pc25.00barN/AAbara, Jennings, et al., 1988Uncertainty assigned by TRC = 0.40 bar; TRC
Pc24.842barN/AMcMicking and Kay, 1965Uncertainty assigned by TRC = 0.4053 bar; TRC
Quantity Value Units Method Reference Comment
Vc0.488l/molN/ADaubert, 1996 
Quantity Value Units Method Reference Comment
ρc2.05 ± 0.02mol/lN/ADaubert, 1996 
ρc2.05mol/lN/AMcMicking and Kay, 1965Uncertainty assigned by TRC = 0.04 mol/l; TRC
Quantity Value Units Method Reference Comment
Δvap39. ± 5.kJ/molAVGN/AAverage of 6 values; Individual data points

Reduced pressure boiling point

Tboil (K) Pressure (bar) Reference Comment
389.21.01Aldrich Chemical Company Inc., 1990BS

Enthalpy of vaporization

ΔvapH (kJ/mol) Temperature (K) Method Reference Comment
33.26390.8N/AMajer and Svoboda, 1985 
39.8300.AStephenson and Malanowski, 1987Based on data from 285. to 392. K.; AC
41.6268.IPStephenson and Malanowski, 1987Based on data from 233. to 283. K. See also Osborn and Douslin, 1974.; AC
38.7 ± 0.1313.CMajer, Svoboda, et al., 1979AC
37.3 ± 0.1333.CMajer, Svoboda, et al., 1979AC
36.0 ± 0.1353.CMajer, Svoboda, et al., 1979AC
38.1330.MMWillingham, Taylor, et al., 1945Based on data from 315. 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 353.57.870.2919559.6Majer 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
233. to 283.4.845621718.531-29.682Osborn and Douslin, 1974Coefficents calculated by NIST from author's data.
314.86 to 391.694.042271337.468-59.457Williamham, Taylor, et al., 1945 

Enthalpy of fusion

ΔfusH (kJ/mol) Temperature (K) Reference Comment
11.92064.19Messerly and Finke, 1971DH
11.92164.2Domalski and Hearing, 1996AC

Entropy of fusion

ΔfusS (J/mol*K) Temperature (K) Reference Comment
72.6064.19Messerly and Finke, 1971DH

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:


References

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

Messerly J.F., 1971
Messerly J.F., Low-temperature thermal properties of 2-methylheptane and 2-methyldecane: the thermodynamic properties of 2-methylalkanes, J. Chem. Thermodyn., 1971, 3, 675-687. [all data]

Colgate S.O., 1990
Colgate S.O., Acoustical determination of ideal gas heat capacities of three C-8 compounds, Fluid Phase Equilib., 1990, 60, 191-203. [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]

Fajans, 1920
Fajans, K., Die Energie der Atombindungen im Diamanten und in aliphatischen Kohlenwasserstoffen, Ber., 1920, 53, 643-665. [all data]

Richards and Jesse, 1910
Richards, T.W.; Jesse, R.H., Jr., The heats of combustion of the octanes and xylenes, J. Am. Chem. Soc., 1910, 32, 268-298. [all data]

Messerly and Finke, 1971
Messerly, J.F.; Finke, H.L., Low-temperature thermal properties of 2-methylheptane and 2-methyldecane: the thermodynamic properties of the 2-methylalkanes, J. Chem. Thermodynam., 1971, 3, 675-687. [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]

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]

Abara, Jennings, et al., 1988
Abara, J.A.; Jennings, D.W.; Kay, W.B.; Teja, A.S., Phase Behavior in the Critical Region of Six Binary Mixtures of 2-Methylalkanes, J. Chem. Eng. Data, 1988, 33, 242. [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]

Ambrose, Cox, et al., 1960
Ambrose, D.; Cox, J.D.; Townsend, R., The critical temperatures of forty organic compounds, Trans. Faraday Soc., 1960, 56, 1452. [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]

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]

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]

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]


Notes

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