Octane

• Formula: C₈H₁₈
• Molecular weight: 114.2285
• IUPAC Standard InChI: InChI=1S/C8H18/c1-3-5-7-8-6-4-2/h3-8H2,1-2H3 Copy

  
• IUPAC Standard InChIKey: TVMXDCGIABBOFY-UHFFFAOYSA-N Copy
• CAS Registry Number: 111-65-9
• Chemical structure:
  This structure is also available as a 2d Mol file or as a computed 3d SD file
  The 3d structure may be viewed using Java or Javascript.
• Isotopologues:
  • Octane-d18-
  • Octane-1,2,3,4,5,6-d13
  • Octane-1,2,3,4-d9
  • Octane-1,2-d5
• Other names: n-Octane; n-C8H18; Oktan; Oktanen; Ottani; UN 1262
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Condensed phase thermochemistry data
  • Reaction thermochemistry data
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Phase change data
  • Henry's Law data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • Fluid Properties
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
  • Reference simulation
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Condensed phase thermochemistry data

Go To: Top, Reaction thermochemistry 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 as indicated in comments:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DH - Eugene S. Domalski and Elizabeth D. Hearing

Constant pressure heat capacity of liquid

Reaction thermochemistry data

Go To: Top, Condensed phase thermochemistry 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: 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

 +  =

By formula: C₈H₁₆ + H₂ = C₈H₁₈

 +  =

By formula: H₂ + C₈H₁₆ = C₈H₁₈

2 +  =

By formula: 2H₂ + C₈H₁₄ = C₈H₁₈

2 +  =

By formula: 2H₂ + C₈H₁₄ = C₈H₁₈

=

By formula: C₈H₁₈ = C₈H₁₈

=

By formula: C₈H₁₈ = C₈H₁₈

=

By formula: C₈H₁₈ = C₈H₁₈

=

By formula: C₈H₁₈ = C₈H₁₈

=

By formula: C₈H₁₈ = C₈H₁₈

=

By formula: C₈H₁₈ = C₈H₁₈

=

By formula: C₈H₁₈ = C₈H₁₈

=

By formula: C₈H₁₈ = C₈H₁₈

=

By formula: C₈H₁₈ = C₈H₁₈

=

By formula: C₈H₁₈ = C₈H₁₈

=

By formula: C₈H₁₈ = C₈H₁₈

=

By formula: C₈H₁₈ = C₈H₁₈

=

By formula: C₈H₁₈ = C₈H₁₈

=

By formula: C₈H₁₈ = C₈H₁₈

=

By formula: C₈H₁₈ = C₈H₁₈

=

By formula: C₈H₁₈ = C₈H₁₈

=

By formula: C₈H₁₈ = C₈H₁₈

 +  =

By formula: H₂ + C₈H₁₆ = C₈H₁₈

 +  =

By formula: H₂ + C₈H₁₆ = C₈H₁₈

 +  =

By formula: H₂ + C₈H₁₆ = C₈H₁₈

 +  =

By formula: H₂ + C₈H₁₆ = C₈H₁₈

2 +  =

By formula: 2H₂ + C₈H₁₄ = C₈H₁₈

 +  =

By formula: H₂ + C₈H₁₆ = C₈H₁₈

2 +  =

By formula: 2H₂ + C₈H₁₄ = C₈H₁₈

4 +  =

By formula: 4H₂ + C₈H₁₀ = C₈H₁₈

3 +  =

By formula: 3H₂ + C₈H₁₂ = C₈H₁₈

4 +  =

By formula: 4H₂ + C₈H₁₀ = C₈H₁₈

=  + 

By formula: C₈H₁₈ = H₂ + C₈H₁₆

=  + 

By formula: C₈H₁₈ = H₂ + C₈H₁₆

=  + 

By formula: C₈H₁₈ = H₂ + C₈H₁₆

=  + 

By formula: C₈H₁₈ = H₂ + C₈H₁₆

=  + 

By formula: C₈H₁₈ = H₂ + C₈H₁₆

=  + 

By formula: C₈H₁₈ = H₂ + C₈H₁₆

=  + 

By formula: C₈H₁₈ = C₈H₁₆ + H₂

Gas phase ion energetics data

Go To: Top, Condensed phase thermochemistry data, Reaction thermochemistry data, References, Notes

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

Data evaluated as indicated in comments:
L - Sharon G. Lias

Data compiled as indicated in comments:
LL - Sharon G. Lias and Joel F. Liebman
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard
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

Appearance energy determinations

References

Go To: Top, Condensed phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics 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]

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]

Rogers, Dejroongruang, et al., 1992
Rogers, D.W.; Dejroongruang, K.; Samuel, S.D.; Fang, W.; Zhao, Y., Enthalpies of hydrogenation of the octenes and the methylheptenes, J. Chem. Thermodyn., 1992, 24, 561-565. [all data]

Rogers and Siddiqui, 1975
Rogers, D.W.; Siddiqui, N.A., Heats of hydrogenation of large molecules. I. Esters of unsaturated fatty acids, J. Phys. Chem., 1975, 79, 574-577. [all data]

Turner, Jarrett, et al., 1973
Turner, R.B.; Jarrett, A.D.; Goebel, P.; Mallon, B.J., Heats of hydrogenation. 9. Cyclic acetylenes and some miscellaneous olefins, J. Am. Chem. Soc., 1973, 95, 790-792. [all data]

Rogers, Dagdagan, et al., 1979
Rogers, D.W.; Dagdagan, O.A.; Allinger, N.L., Heats of hydrogenation and formation of linear alkynes and a molecular mechanics interpretation, J. Am. Chem. Soc., 1979, 101, 671-676. [all data]

Sicher, Svoboda, et al., 1966
Sicher, J.; Svoboda, M.; Zavada, J.; Turner, R.B.; Goebel, P., Sterochemical studies - XXXVI. An approach to conformational analysis of medium ring compounds. Unsaturated ten-membered ring derivates, Tetrahedron, 1966, 22, 659-671. [all data]

Molnar, Rachford, et al., 1984
Molnar, A.; Rachford, R.; Smith, G.V.; Liu, R., Heats of hydrogenation by a simple and rapid flow calorimetric method, Appl. Catal., 1984, 9, 219-223. [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]

Flitcroft, Skinner, et al., 1957
Flitcroft, T.; Skinner, H.A.; Whiting, M.C., Heats of hydrogenation Part 1.-Dodeca-3:9 and -5:7 Diynes, Trans. Faraday Soc., 1957, 53, 784-790. [all data]

Flitcroft and Skinner, 1958
Flitcroft, T.L.; Skinner, H.A., Heats of hydrogenation Part 2.-Acetylene derivatives, Trans. Faraday Soc., 1958, 54, 47-53. [all data]

Roth, Scholz, et al., 1982
Roth, W.R.; Scholz, B.P.; Breuckmann, R.; Jelich, K.; Lennartz, H.W., Thermolysis of 1,2,6,7-octatetraene, Chem. Ber., 1982, 115, 1934-1946. [all data]

Eliseev, 1986
Eliseev, N.A., Thermodynamic calculation of the equilibrium composition of isomeric octenes in dehydrogenation of n-octane, Izv. Vyssh. Uchebn. Zaved., Khim. Khim. Tekhnol., 1986, 29, 26-29. [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, 1982
Lias, S.G., Thermochemical information from ion-molecule rate constants, Ion Cyclotron Reson. Spectrom. 1982, 1982, 409. [all data]

Mautner(Meot-Ner), Sieck, et al., 1981
Mautner(Meot-Ner), M.; Sieck, L.W.; Ausloos, P., Ionization of normal alkanes: Enthalpy, entropy, structural, and isotope effects, J. Am. Chem. Soc., 1981, 103, 5342. [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]

Potzinger and Bunau, 1969
Potzinger, P.; Bunau, G.v., Empirische Beruksichtigung von Uberschussenergien bei der Auftrittspotentialbestimmung, Ber. Bunsen-Ges. Phys. Chem., 1969, 73, 466. [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]

Lewis and Hamill, 1970
Lewis, D.; Hamill, W.H., Excited states of neutral molecular fragments from appearance potentials by electron impact in a mass spectrometer, J. Chem. Phys., 1970, 52, 6348. [all data]

Notes

Go To: Top, Condensed phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, References

• Symbols used in this document:
  

  AE	Appearance energy
  Cp,liquid	Constant pressure heat capacity of liquid
  IE (evaluated)	Recommended ionization energy
  S°liquid	Entropy of liquid at standard conditions
  ΔcH°liquid	Enthalpy of combustion of liquid at standard conditions
  ΔfH°liquid	Enthalpy of formation of liquid at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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