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Pentane, 2,2,4-trimethyl-

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Gas phase thermochemistry data

Go To: Top, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry 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 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-53.57 ± 0.32kcal/molCcbProsen and Rossini, 1945ALS

Constant pressure heat capacity of gas

Cp,gas (cal/mol*K) Temperature (K) Reference Comment
31.209200.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
41.580273.15
45.03 ± 0.1298.15
45.280300.
58.461400.
70.129500.
80.201600.
88.901700.
96.401800.
102.90900.
108.701000.
113.701100.
118.201200.
122.001300.
126.001400.
129.001500.

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-61.98 ± 0.32kcal/molCcbProsen and Rossini, 1945ALS
Quantity Value Units Method Reference Comment
Deltacliquid-1305.29 ± 0.30kcal/molCcbProsen and Rossini, 1945Corresponding «DELTA»fliquid = -61.95 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS
Quantity Value Units Method Reference Comment
liquid78.401cal/mol*KN/APitzer K.S., 1940DH
liquid75.19cal/mol*KN/AParks, Huffman, et al., 1930Extrapolation below 90 K, 66.53 J/mol*K.; DH

Constant pressure heat capacity of liquid

Cp,liquid (cal/mol*K) Temperature (K) Reference Comment
57.957298.15Costas, Huu, et al., 1988DH
57.957298.15Perez-Casas, Aicart, et al., 1988DH
57.292298.15Shiohama, Ogawa, et al., 1988DH
56.848293.15Kalali, Kohler, et al., 1987T = 293.15, 313.15 K.; DH
57.0915298.15Fortier and Benson, 1976Average of three values.; DH
56.84298.15Rajagopal and Subrahmanyam, 1974T = 298.15 to 323.15 K.; DH
56.84298.15Subrahmanyam and Rajagopal, 1973T = 298 to 323 K.; DH
55.86300.Auerbach, Sage, et al., 1950T = 300 to 366 K. Cp given as 0.4980 Btu/lb*R at 80 F.; DH
57.020298.15Osborne and Ginnings, 1947T = 283 to 318 K.; DH
57.600301.9Pitzer K.S., 1940T = 15 to 318 K. Value is unsmoothed experimental datum.; DH
55.90295.2Parks, Huffman, et al., 1930T = 88 to 295 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:
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny, director
BS - Robert L. Brown and Stephen E. Stein
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
Tboil372.4 ± 0.2KAVGN/AAverage of 49 out of 52 values; Individual data points
Quantity Value Units Method Reference Comment
Tfus165.77 ± 0.06KAVGN/AAverage of 37 out of 44 values; Individual data points
Quantity Value Units Method Reference Comment
Ttriple165.760KN/AStreiff, 1959Uncertainty assigned by TRC = 0.4 K; TRC
Ttriple165.3KN/AParks, Huffman, et al., 1930, 2Uncertainty assigned by TRC = 0.2 K; TRC
Quantity Value Units Method Reference Comment
Tc543.9 ± 0.4KAVGN/AAverage of 6 values; Individual data points
Quantity Value Units Method Reference Comment
Pc25.4 ± 0.2atmN/ADaubert, 1996 
Pc25.340atmN/AMcMicking and Kay, 1965Uncertainty assigned by TRC = 0.4000 atm; TRC
Pc25.3080atmN/AKay and Warzel, 1951Uncertainty assigned by TRC = 0.09998 atm; TRC
Pc25.5000atmN/ABeattie and Edwards, 1948Uncertainty assigned by TRC = 0.1499 atm; from observed isotherms in critical region; TRC
Quantity Value Units Method Reference Comment
Vc0.468l/molN/ADaubert, 1996 
Vc0.482l/molN/ABeattie and Edwards, 1948Uncertainty assigned by TRC = 0.02 l/mol; from observed isotherms in the critical region; TRC
Quantity Value Units Method Reference Comment
rhoc2.14 ± 0.02mol/lN/ADaubert, 1996 
rhoc2.13mol/lN/AMcMicking and Kay, 1965Uncertainty assigned by TRC = 0.04 mol/l; TRC
rhoc2.13mol/lN/AKay and Warzel, 1951Uncertainty assigned by TRC = 0.03 mol/l; TRC
Quantity Value Units Method Reference Comment
Deltavap8.39 ± 0.05kcal/molAVGN/AAverage of 7 values; Individual data points

Enthalpy of vaporization

DeltavapH (kcal/mol) Temperature (K) Method Reference Comment
7.359372.4N/AMajer and Svoboda, 1985 
8.63304.N/AWu, Pividal, et al., 1991Based on data from 289. - 333. K.; AC
7.55438.AStephenson and Malanowski, 1987Based on data from 423. - 523. K.; AC
7.70387.AStephenson and Malanowski, 1987Based on data from 372. - 416. K.; AC
7.53428.AStephenson and Malanowski, 1987Based on data from 413. - 494. K.; AC
7.50505.AStephenson and Malanowski, 1987Based on data from 490. - 544. K.; AC
9.73209.AStephenson and Malanowski, 1987Based on data from 194. - 299. K. See also Milazzo, 1956.; AC
8.32312.A,MMStephenson and Malanowski, 1987Based on data from 297. - 374. K. See also Willingham, Taylor, et al., 1945.; AC
8.22 ± 0.02313.CSvoboda, Charvátová, et al., 1982AC
7.98 ± 0.02328.CSvoboda, Charvátová, et al., 1982AC
7.79 ± 0.02343.CSvoboda, Charvátová, et al., 1982AC
7.58 ± 0.02358.CSvoboda, Charvátová, et al., 1982AC
7.41 ± 0.02368.CSvoboda, Charvátová, et al., 1982AC
8.20 ± 0.02313.CMajer, Svoboda, et al., 1979AC
7.93 ± 0.02333.CMajer, Svoboda, et al., 1979AC
7.65 ± 0.02353.CMajer, Svoboda, et al., 1979AC
7.41371.CPitzer K.S., 1940AC
8.10333.EBSmith, 1940Based on data from 318. - 399. 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. - 353.12.020.2668543.9Majer 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
194.64 - 298.443.941651282.332-48.444Milazzo, 1956, 2Coefficents calculated by NIST from author's data.
297.51 - 373.283.931081257.84-52.415Williamham, Taylor, et al., 1945 

Enthalpy of fusion

DeltafusH (kcal/mol) Temperature (K) Reference Comment
2.2016165.79Pitzer K.S., 1940DH
2.16165.3Domalski and Hearing, 1996AC
2.161165.3Parks, Huffman, et al., 1930DH

Entropy of fusion

DeltafusS (cal/mol*K) Temperature (K) Reference Comment
13.28165.79Pitzer K.S., 1940DH
13.07165.3Parks, Huffman, et al., 1930DH

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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

1-Pentene, 2,4,4-trimethyl- + Hydrogen = Pentane, 2,2,4-trimethyl-

By formula: C8H16 + H2 = C8H18

Quantity Value Units Method Reference Comment
Deltar-25.5kcal/molChydTurner, Nettleton, et al., 1958liquid phase; solvent: Acetic acid
Deltar-26.99 ± 0.06kcal/molChydDolliver, Gresham, et al., 1937gas phase; Reanalyzed by Cox and Pilcher, 1970, Original value = -27.24 ± 0.06 kcal/mol; At 355 °K
Deltar-28.58 ± 0.80kcal/molChydCrawford and Parks, 1936liquid phase

2-Pentene, 2,4,4-trimethyl- + Hydrogen = Pentane, 2,2,4-trimethyl-

By formula: C8H16 + H2 = C8H18

Quantity Value Units Method Reference Comment
Deltar-26.8kcal/molChydTurner, Nettleton, et al., 1958liquid phase; solvent: Acetic acid
Deltar-28.39kcal/molChydDolliver, Gresham, et al., 1937gas phase; At 355 °K

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

By formula: C8H18 = C8H18

Quantity Value Units Method Reference Comment
Deltar-2.24 ± 0.25kcal/molCisoProsen and Rossini, 1945, 2liquid phase; Calculated from «DELTA»Hc

IR Spectrum

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Data compiled by: Coblentz Society, Inc.

Data compiled by: NIST Mass Spectrometry Data Center, William E. Wallace, director


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.
Origin Japan AIST/NIMC Database- Spectrum MS-NW- 662
NIST MS number 229172

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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]

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 K.S., 1940
Pitzer K.S., The thermodynamics of n-heptane and 2,2,4-trimethylpentane, including heat capacities, heats of fusion and vaporization and entropies, J. Am. Chem. Soc., 1940, 62, 1224-1227. [all data]

Parks, Huffman, et al., 1930
Parks, G.S.; Huffman, H.M.; Thomas, S.B., Thermal data on organic compounds. VI. The heat capacities, entropies and free energies of some saturated, non-benzenoid hydrocarbons, J. Am. Chem. Soc., 1930, 52, 1032-1041. [all data]

Costas, Huu, et al., 1988
Costas, M.; Huu, V.T.; Patterson, D.; Caceres-Alonso, M.; Tardajos, G.; Aicart, E., Liquid structure and second-order mixing functions for l-chloronaphthalene with linear and branched alkanes, J. Chem. Soc., Faraday Trans., 1988, 1 84(5), 1603-1616. [all data]

Perez-Casas, Aicart, et al., 1988
Perez-Casas, S.; Aicart, E.; Trojo, L.M.; Costas, M., Excess heat capacity. Chlorobenzene-2,2,4,4,6,8,8-heptamethylnonane, Int. Data Ser., Sel. Data Mixtures, 1988, (2)A, 123. [all data]

Shiohama, Ogawa, et al., 1988
Shiohama, Y.; Ogawa, H.; Murakami, S.; Fujihara, I., Excess molar isobaric heat capacities and isentropic compressibilities of (cis- or trans-decalin + benzene or toluene or iso-octane or n-heptane) at 298.15 K, J. Chem. Thermodynam., 1988, 20, 1183-1189. [all data]

Kalali, Kohler, et al., 1987
Kalali, H.; Kohler, F.; Svejda, P., Excess properties of the mixture bis(2-dichlorethyl)ether (chlorex) + 2,2,4-trimethylpentane (isooctane), Monatsh. Chem., 1987, 118, 1-18. [all data]

Fortier and Benson, 1976
Fortier, J.-L.; Benson, G.C., Excess heat capacities of binary liquid mixtures determined with a Picker flow calorimeter, J. Chem. Thermodynam., 1976, 8, 411-423. [all data]

Rajagopal and Subrahmanyam, 1974
Rajagopal, E.; Subrahmanyam, S.V., Excess function of VE,(dVE/dp)T, and CpE of isooctane + benzene and + toluene, J. Chem. Thermodynam., 1974, 6, 873-876. [all data]

Subrahmanyam and Rajagopal, 1973
Subrahmanyam, S.V.; Rajagopal, E., Excess thermodynamic functions of the systems isooctane + carbon tetrachloride and isooctane + cyclohexane, Z. Phys. Chem. [NF], 1973, 85, 256-268. [all data]

Auerbach, Sage, et al., 1950
Auerbach, C.E.; Sage, B.H.; Lacey, W.N., Isobaric heat capacities at bubble point, Ind. Eng. Chem., 1950, 42, 110-113. [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]

Streiff, 1959
Streiff, A.J., Unpublished 1959, 1959. [all data]

Parks, Huffman, et al., 1930, 2
Parks, G.S.; Huffman, H.M.; Thomas, S.B., Thermal Data on Organic Compounds VI. The Heat Capacities, Entropies and Free Energies of Some Saturated, Non-Benzenoid Hydrocarbons, J. Am. Chem. Soc., 1930, 52, 1032-41. [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]

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]

Kay and Warzel, 1951
Kay, W.B.; Warzel, F.M., 2,2,4-Trimethylpentane (Isooctane), Vapor Pressure, Critical Constants and Saturated Vapor and Liquid Densities, Ind. Eng. Chem., 1951, 43, 1150-2. [all data]

Beattie and Edwards, 1948
Beattie, J.A.; Edwards, D.G., The Vapor Pressure, Orthobaric Densities, and Critical Constants of 2,2,4-Trimethylpentane, J. Am. Chem. Soc., 1948, 70, 3382. [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]

Wu, Pividal, et al., 1991
Wu, Huey S.; Pividal, Katherine A.; Sandler, Stanley I., Vapor-liquid equilibria of hydrocarbons and fuel oxygenates, J. Chem. Eng. Data, 1991, 36, 4, 418-421, https://doi.org/10.1021/je00004a021 . [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]

Milazzo, 1956
Milazzo, G., Ann. Chim. (Rome), 1956, 46, 1105. [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]

Svoboda, Charvátová, et al., 1982
Svoboda, Václav; Charvátová, Vladimíra; Majer, Vladimír; Hynek, Vladimír, Determination of heats of vaporization and some other thermodynamic properties for four substituted hydrocarbons, Collect. Czech. Chem. Commun., 1982, 47, 2, 543-549, https://doi.org/10.1135/cccc19820543 . [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]

Smith, 1940
Smith, E.R., Boiling points of n-heptane and 2,2,4-trimethylpentane over the range 100- to 1,500-millimeter pressure, J. RES. NATL. BUR. STAN., 1940, 24, 3, 229-17, https://doi.org/10.6028/jres.024.010 . [all data]

Milazzo, 1956, 2
Milazzo, G., Tensioni di Vapore di Alcune Sostanze Organiche a Bassa Temperatura, Ann. Chim. (Rome), 1956, 46, 1105-1111. [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]

Turner, Nettleton, et al., 1958
Turner, R.B.; Nettleton, J.E.; Perelman, Heats of Hydrogenation. VI. Heats of hydrogenation of some substituted ethylenes, J. Am. Chem. Soc., 1958, 80, 1430-1433. [all data]

Dolliver, Gresham, et al., 1937
Dolliver, M.a.; Gresham, T.L.; Kistiakowsky, G.B.; Vaughan, W.E., Heats of organic reactions. V. Heats of hydrogenation of various hydrocarbons, J. Am. Chem. Soc., 1937, 59, 831-841. [all data]

Cox and Pilcher, 1970
Cox, J.D.; Pilcher, G., Thermochemistry of Organic and Organometallic Compounds, Academic Press, New York, 1970, 1-636. [all data]

Crawford and Parks, 1936
Crawford, B.L., Jr.; Parks, G.S., The heat of hydrogenation of diisobutylene, J. Am. Chem. Soc., 1936, 58, 373. [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