Octane

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Gas phase thermochemistry data

Go To: Top, Condensed phase thermochemistry data, Phase change data, Henry's Law 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 as indicated in comments:
DRB - Donald R. Burgess, Jr.
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-208.7kJ/molN/AGood, 1972Value computed using ΔfHliquid° value of -250.3±1.8 kj/mol from Good, 1972 and ΔvapH° value of 41.6 kj/mol from Prosen and Rossini, 1945.; DRB
Δfgas-208.4 ± 0.67kJ/molCcbProsen and Rossini, 1945see Prosen and Rossini, 1944; ALS
Quantity Value Units Method Reference Comment
gas467.06 ± 0.92J/mol*KN/AScott D.W., 1974This reference does not contain the original experimental data. Experimental entropy value is based on the results [ Messerly J.F., 1967] for S(liquid).; GT

Constant pressure heat capacity of gas

Cp,gas (J/mol*K) Temperature (K) Reference Comment
232.74 ± 0.47385.65Hossenlopp I.A., 1981Please also see Barrow G.M., 1951.; GT
238.95 ± 0.48398.15
242.67405.7
250.59 ± 0.50423.15
263.02 ± 0.53448.15
270.70462.5
274.84 ± 0.55473.15
285.98 ± 0.57498.15
295.39522.7
297.00 ± 0.59523.15

Constant pressure heat capacity of gas

Cp,gas (J/mol*K) Temperature (K) Reference Comment
144.77200.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., 1944, Pitzer K.S., 1946].; GT
175.69273.15
187.8 ± 0.4298.15
188.70300.
239.74400.
286.81500.
326.77600.
360.24700.
388.28800.
411.71900.
431.371000.
448.521100.
463.171200.
476.981300.
489.531400.
497.901500.

Condensed phase thermochemistry data

Go To: Top, Gas phase thermochemistry data, Phase change data, Henry's Law 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 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-250.3 ± 1.8kJ/molCcbGood, 1972ALS
Δfliquid-250.0 ± 0.84kJ/molCcbProsen and Rossini, 1945see Prosen and Rossini, 1944; ALS
Quantity Value Units Method Reference Comment
Δcliquid-5430. ± 100.kJ/molAVGN/AAverage of 6 values; Individual data points
Quantity Value Units Method Reference Comment
liquid361.20J/mol*KN/AFinke, Gross, et al., 1954DH
liquid359.8J/mol*KN/AHuffman, Parks, et al., 1931Extrapolation below 90 K, 75.73 J/mol*K.; DH
liquid359.8J/mol*KN/AParks, Huffman, et al., 1930Extrapolation below 90 K, 77.19 J/mol*K.; DH

Constant pressure heat capacity of liquid

Cp,liquid (J/mol*K) Temperature (K) Reference Comment
254.7299.Czarnota, 1993DH
262.20318.15Banipal, Garg, et al., 1991T = 318 to 373 K. p = 0.1 MPa.; DH
255.68298.15Trejo, Costas, et al., 1991DH
255.68298.15Andreoli-Ball, Patterson, et al., 1988DH
255.68298.15Perez-Casas, Aicart, et al., 1988DH
254.11298.15Benson and D'Arcy, 1986DH
255.68298.15Tardajos, Aicart, et al., 1986DH
254.18298.15Lainez, Grolier, et al., 1985DH
253.72298.15Lainez, Rodrigo, et al., 1985DH
252.4297.54Grigor'ev and Andolenko, 1984T = 297 to 410 K. Unsmoothed experimental datum given as 2.210 KJ/kg*K.; DH
254.02298.15Roux, Grolier, et al., 1984DH
252.4298.Zaripov, 1982T = 298, 323, 363 K.; DH
254.07298.15Grolier, Inglese, et al., 1981DH
252.92298.15Shakirov and Lyubarskii, 1980T = 65 to 300 K.; DH
253.2298.Grigor'ev, Rastorguev, et al., 1975T = 305 to 463 K.; DH
254.14298.15Finke, Gross, et al., 1954T = 12 to 300 K.; DH
253.93299.8Connolly, Sage, et al., 1951T = 80 to 200 F.; DH
253.89298.15Osborne and Ginnings, 1947T = 293 to 318 K.; DH
251.5298.3Huffman, Parks, et al., 1931T = 92 to 298 K. Value is unsmoothed experimental datum.; DH
247.7293.7Parks, Huffman, et al., 1930T = 85 to 294 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
Tboil398.7 ± 0.5KAVGN/AAverage of 75 out of 89 values; Individual data points
Quantity Value Units Method Reference Comment
Tfus216.3 ± 0.3KAVGN/AAverage of 39 out of 41 values; Individual data points
Quantity Value Units Method Reference Comment
Ttriple216.2 ± 0.6KAVGN/AAverage of 9 values; Individual data points
Quantity Value Units Method Reference Comment
Tc568.9 ± 0.5KAVGN/AAverage of 23 values; Individual data points
Quantity Value Units Method Reference Comment
Pc24.9 ± 0.1barAVGN/AAverage of 12 values; Individual data points
Quantity Value Units Method Reference Comment
Vc0.492l/molN/AAmbrose and Tsonopoulos, 1995 
Quantity Value Units Method Reference Comment
ρc2.034 ± 0.007mol/lAVGN/AAverage of 7 values; Individual data points
Quantity Value Units Method Reference Comment
Δvap41. ± 4.kJ/molAVGN/AAverage of 10 values; Individual data points

Enthalpy of vaporization

ΔvapH (kJ/mol) Temperature (K) Method Reference Comment
34.41398.8N/AMajer and Svoboda, 1985 
39.4338.EBEwing and Ochoa, 2003Based on data from 323. to 563. K.; AC
41.0312.AStephenson and Malanowski, 1987Based on data from 297. to 400. K.; AC
44.4263.AStephenson and Malanowski, 1987Based on data from 216. to 278. K.; AC
36.3411.AStephenson and Malanowski, 1987Based on data from 396. to 432. K.; AC
35.5443.AStephenson and Malanowski, 1987Based on data from 428. to 510. K.; AC
34.9521.AStephenson and Malanowski, 1987Based on data from 506. to 569. K.; AC
41.2310.N/APaul, Krug, et al., 1986Based on data from 295. to 402. K.; AC
41.9313.N/AMichou-Saucet, Jose, et al., 1984Based on data from 298. to 333. K.; AC
40.5 ± 0.1313.CMajer, Svoboda, et al., 1979AC
39.1 ± 0.1333.CMajer, Svoboda, et al., 1979AC
37.8 ± 0.1353.CMajer, Svoboda, et al., 1979AC
43.0282.N/ACarruth and Kobayashi, 1973Based on data from 217. to 297. K.; AC
38.0 ± 0.1311.CMcKay and Sage, 1960AC
36.7 ± 0.1328.CMcKay and Sage, 1960AC
35.4 ± 0.1344.CMcKay and Sage, 1960AC
39.2341.MMWillingham, Taylor, et al., 1945Based on data from 326. to 400. 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 426.
A (kJ/mol) 58.46
α 0.1834
β 0.3324
Tc (K) 568.8
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 Comment
216.59 to 297.105.20121936.281-20.143Carruth and Kobayashi, 1973Coefficents calculated by NIST from author's data.
326.08 to 399.724.048671355.126-63.633Williamham, Taylor, et al., 1945 

Enthalpy of sublimation

ΔsubH (kJ/mol) Temperature (K) Method Reference Comment
68.1216.BBondi, 1963AC

Enthalpy of fusion

ΔfusH (kJ/mol) Temperature (K) Method Reference Comment
20.740216.38N/AFinke, Gross, et al., 1954DH
21.8216.6DSCMondieig, Rajabalee, et al., 2004AC
20.74216.4N/ADomalski and Hearing, 1996AC
20.652215.8N/AHuffman, Parks, et al., 1931DH
20.092215.6N/AParks, Huffman, et al., 1930DH

Entropy of fusion

ΔfusS (J/mol*K) Temperature (K) Reference Comment
95.85216.38Finke, Gross, et al., 1954DH
95.7215.8Huffman, Parks, et al., 1931DH
93.19215.6Parks, Huffman, et al., 1930DH

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

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change 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: 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
0.00297800.XN/A 
0.00020 QN/A missing citation give several references for the Henry's law constants but don't assign them to specific species.
0.00034 LN/A 
0.00031 VN/A 

References

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

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Good, 1972
Good, W.D., The enthalpies of combustion and formation of n-octane and 2,2,3,3-tetramethylbutane, J. Chem. Thermodyn., 1972, 4, 709-714. [all data]

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]

Prosen and Rossini, 1944
Prosen, E.J.; Rossini, F.D., Heats of combustion of eight normal paraffin hydrocarbons in the liquid state, J. Res. NBS, 1944, 33, 255-272. [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]

Messerly J.F., 1967
Messerly J.F., Low-temperature thermal data for n-pentane, n-heptadecane, and n-octadecane. Revised thermodynamic functions for the n-alkanes, C5-C18, J. Chem. Eng. Data, 1967, 12, 338-346. [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, 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., 1944
Pitzer K.S., Thermodynamics of gaseous paraffins. Specific heat and related properties, Ind. Eng. Chem., 1944, 36, 829-831. [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]

Finke, Gross, et al., 1954
Finke, H.L.; Gross, M.E.; Waddington, G.; Huffman, H.M., Low-temperature thermal data for the nine normal paraffin hydrocarbons from octane to hexadecane, J. Am. Chem. Soc., 1954, 76, 333-341. [all data]

Huffman, Parks, et al., 1931
Huffman, H.M.; Parks, G.S.; Barmore, M., Thermal data on organic compounds. X. Further studies on the heat capacities, entropies and free energies of hydrocarbons, J. Am. Chem. Soc., 1931, 53, 3876-3888. [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]

Czarnota, 1993
Czarnota, I., Heat capacity of octane at high pressures, J. Chem. Thermodynam., 1993, 25, 355-359. [all data]

Banipal, Garg, et al., 1991
Banipal, T.S.; Garg, S.K.; Ahluwalia, J.C., Heat capacities and densities of liquid n-octane, n-nonane, n-decane, and n-hexadecane at temperatures from 318.15 to 373.15 K and at pressures up to 10 MPa, J. Chem. Thermodynam., 1991, 23, 923-931. [all data]

Trejo, Costas, et al., 1991
Trejo, L.M.; Costas, M.; Patterson, D., Excess heat capacity of organic mixtures, Internat. DATA Series, Selected Data Mixt., 1991, Ser. [all data]

Andreoli-Ball, Patterson, et al., 1988
Andreoli-Ball, L.; Patterson, D.; Costas, M.; Caceres-Alonso, M., Heat capacity and corresponding states in alkan-1-ol-n-alkane systems, J. Chem. Soc., Faraday Trans. 1, 1988, 84(11), 3991-4012. [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]

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]

Tardajos, Aicart, et al., 1986
Tardajos, G.; Aicart, E.; Costas, M.; Patterson, D., Liquid structure and second-order mixing functions for benzene, toluene, and p-xylene with n-alkanes, J. Chem. Soc., Faraday Trans., 1986, 1 82, 2977-2987. [all data]

Lainez, Grolier, et al., 1985
Lainez, A.; Grolier, J.-P.E.; Wilhelm, E., Excess molar heat capacity and excess molar volume of 1,6-dichlorohexane + n-octane, Thermochim. Acta, 1985, 91, 243-248. [all data]

Lainez, Rodrigo, et al., 1985
Lainez, A.; Rodrigo, M.; Roux, A.H.; Grolier, J.-P.E.; Wilhelm, E., Relations between structure and thermodynamic properties. Heat capacities of polar substances (nitrobenzene and benzonitrile) in alkane solutions, Calorim. Anal. Therm., 1985, 16, 153-158. [all data]

Grigor'ev and Andolenko, 1984
Grigor'ev, B.A.; Andolenko, R.A., Investigation of the isobaric heat capacity of n-paraffinic hydrocarbons at atmospheric pressure, Izv. Vyssh. Ucheb. Zaved., Neft i Gaz, 1984, (2), 60-62. [all data]

Roux, Grolier, et al., 1984
Roux, A.H.; Grolier, J.-P.E.; Inglese, A.; Wilhelm, E., Excess molar enthalpies, excess molar heat capacities and excess molar volumes of (fluorobenzene + an n-alkane), Ber. Bunsenges. Phys. Chem., 1984, 88, 986-992. [all data]

Zaripov, 1982
Zaripov, Z.I., Experimental study of the isobaric heat capacity of liquid organic compounds with molecular weights of up to 4000 a.e.m., 1982, Teplomassoobmen Teplofiz. [all data]

Grolier, Inglese, et al., 1981
Grolier, J.P.E.; Inglese, A.; Roux, A.H.; Wilhelm, E., Thermodynamics of (1-chloronaphthalene + n-alkane): excess enthalpies, excess volumes and excess heat capacities, Ber. Bunsenges. Phys. Chem., 1981, 85, 768-772. [all data]

Shakirov and Lyubarskii, 1980
Shakirov, R.F.; Lyubarskii, M.V., Low-temperature heat capacity and thermodynamic functions of methyl trichlorothioacrylate, SPSTL Deposited Publication 3 KhP-D80, 1980, 19p. [all data]

Grigor'ev, Rastorguev, et al., 1975
Grigor'ev, B.A.; Rastorguev, Yu.L.; Yanin, G.S., Experimental determination of the isobaric specific heat of n-alkanes, Iz. Vyssh. Uchebn. Zaved. Neft Gaz 18, 1975, No.10, 63-66. [all data]

Connolly, Sage, et al., 1951
Connolly, T.J.; Sage, B.H.; Lacey, W.N., Isobaric heat capacities at bubble point. n-Hexane, methylcyclopentane, and n-octane, Ind. Eng. Chem., 1951, 43, 946-950. [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]

Ambrose and Tsonopoulos, 1995
Ambrose, D.; Tsonopoulos, C., Vapor-Liquid Critical Properties of Elements and Compounds. 2. Normal Alkenes, J. Chem. Eng. Data, 1995, 40, 531-546. [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]

Ewing and Ochoa, 2003
Ewing, M.B.; Ochoa, J.C. Sanchez, The vapour pressures of n-octane determined using comparative ebulliometry, Fluid Phase Equilibria, 2003, 210, 2, 277-285, https://doi.org/10.1016/S0378-3812(03)00174-2 . [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]

Paul, Krug, et al., 1986
Paul, Hanns-Ingolf; Krug, Joseph; Knapp, Helmut, Measurements of VLE, hE and vE for binary mixtures of n-alkanes with n-alkylbenzenes, Thermochimica Acta, 1986, 108, 9-27, https://doi.org/10.1016/0040-6031(86)85073-0 . [all data]

Michou-Saucet, Jose, et al., 1984
Michou-Saucet, Marie-Annie; Jose, Jacques; Michou-Saucet, Christian; Merlin, J.C., Pressions de vapeur et enthalpies libres d'exces de systemes binaires: Hexamethylphosphorotriamide (HMPT) + n-hexane; n-heptane; n-octane: A 298,15 K; 303,15 K; 313,15 K; 323,15 K; 333,15 K, Thermochimica Acta, 1984, 75, 1-2, 85-106, https://doi.org/10.1016/0040-6031(84)85009-1 . [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]

Carruth and Kobayashi, 1973
Carruth, Grant F.; Kobayashi, Riki, Vapor pressure of normal paraffins ethane through n-decane from their triple points to about 10 mm mercury, J. Chem. Eng. Data, 1973, 18, 2, 115-126, https://doi.org/10.1021/je60057a009 . [all data]

McKay and Sage, 1960
McKay, R.A.; Sage, B.H., Latent Heat of Vaporization for n-Octane., J. Chem. Eng. Data, 1960, 5, 1, 21-24, https://doi.org/10.1021/je60005a005 . [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]

Bondi, 1963
Bondi, A., Heat of Siblimation of Molecular Crystals: A Catalog of Molecular Structure Increments., J. Chem. Eng. Data, 1963, 8, 3, 371-381, https://doi.org/10.1021/je60018a027 . [all data]

Mondieig, Rajabalee, et al., 2004
Mondieig, D.; Rajabalee, F.; Metivaud, V.; Oonk, H.A.J.; Cuevas-Diarte, M.A., n -Alkane Binary Molecular Alloys, Chem. Mater., 2004, 16, 5, 786-798, https://doi.org/10.1021/cm031169p . [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

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