Methane

• Formula: CH₄
• Molecular weight: 16.0425
• IUPAC Standard InChI: InChI=1S/CH4/h1H4 Copy

  
• IUPAC Standard InChIKey: VNWKTOKETHGBQD-UHFFFAOYSA-N Copy
• CAS Registry Number: 74-82-8
• 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.
• Other names: Marsh gas; Methyl hydride; CH4; Fire Damp; R 50; Biogas; R 50 (refrigerant)
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Reaction thermochemistry data (reactions 1 to 50)
  • Vibrational and/or electronic energy levels
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data: reactions 51 to 100, reactions 101 to 112
  • Henry's Law data
  • Gas phase ion energetics data
  • Ion clustering data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • Fluid Properties
• Data at other public NIST sites:
  • Microwave spectra (on physics lab web site)
  • Electron-Impact Ionization Cross Sections (on physics web site)
  • Gas Phase Kinetics Database
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Reaction 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:
B - John E. Bartmess
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
MS - José A. Martinho Simões
ALS - 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.

Reactions 1 to 50

CH₃^- +  =

By formula: CH₃^- + H⁺ = CH₄

(CH₅⁺ • ) +  = (CH₅⁺ • 2)

By formula: (CH₅⁺ • CH₄) + CH₄ = (CH₅⁺ • 2CH₄)

CH₅⁺ +  = (CH₅⁺ • )

By formula: CH₅⁺ + CH₄ = (CH₅⁺ • CH₄)

C₂H₅⁺ +  = (C₂H₅⁺ • )

By formula: C₂H₅⁺ + CH₄ = (C₂H₅⁺ • CH₄)

( • 2) +  = ( • 3)

By formula: (Co⁺ • 2CH₄) + CH₄ = (Co⁺ • 3CH₄)

Enthalpy of reaction

Free energy of reaction

 +  = ( • )

By formula: Co⁺ + CH₄ = (Co⁺ • CH₄)

Enthalpy of reaction

( • ) +  = ( •  • )

By formula: (Co⁺ • CH₄) + H₂ = (Co⁺ • H₂ • CH₄)

Enthalpy of reaction

( • ) +  = ( •  • )

By formula: (Co⁺ • H₂) + CH₄ = (Co⁺ • CH₄ • H₂)

Enthalpy of reaction

 (g) = C₅MnO₅ (g) +  (g)

By formula: C₆H₃MnO₅ (g) = C₅MnO₅ (g) + CH₄ (g)

( • ) +  = ( • 2)

By formula: (Co⁺ • CH₄) + CH₄ = (Co⁺ • 2CH₄)

Enthalpy of reaction

(CH₅⁺ • 2) +  = (CH₅⁺ • 3)

By formula: (CH₅⁺ • 2CH₄) + CH₄ = (CH₅⁺ • 3CH₄)

(CH₅⁺ • 3) +  = (CH₅⁺ • 4)

By formula: (CH₅⁺ • 3CH₄) + CH₄ = (CH₅⁺ • 4CH₄)

 (g) + CH₃BrMg (solution) =  (solution) + Br₂Mg (solution)

By formula: HBr (g) + CH₃BrMg (solution) = CH₄ (solution) + Br₂Mg (solution)

( • ) +  = ( •  • )

By formula: (Co⁺ • CH₄) + C₂H₆ = (Co⁺ • C₂H₆ • CH₄)

Enthalpy of reaction

C₆₃H₉₁CoN₁₃O₁₄P (solution) =  (solution) +  (solution)

By formula: C₆₃H₉₁CoN₁₃O₁₄P (solution) = C₆₃H₈₈CoN₁₄O₁₄P (solution) + CH₄ (solution)

C₃H₇⁺ +  = (C₃H₇⁺ • )

By formula: C₃H₇⁺ + CH₄ = (C₃H₇⁺ • CH₄)

 +  =  + 

By formula: HI + CH₃I = CH₄ + I₂

(C₂H₅⁺ • 9) +  = (C₂H₅⁺ • 10)

By formula: (C₂H₅⁺ • 9CH₄) + CH₄ = (C₂H₅⁺ • 10CH₄)

(C₃H₇⁺ • 7) +  = (C₃H₇⁺ • 8)

By formula: (C₃H₇⁺ • 7CH₄) + CH₄ = (C₃H₇⁺ • 8CH₄)

(C₄H₉⁺ • 8) +  = (C₄H₉⁺ • 9)

By formula: (C₄H₉⁺ • 8CH₄) + CH₄ = (C₄H₉⁺ • 9CH₄)

(CH₅⁺ • 8) +  = (CH₅⁺ • 9)

By formula: (CH₅⁺ • 8CH₄) + CH₄ = (CH₅⁺ • 9CH₄)

( • ) +  = ( •  • )

By formula: (Co⁺ • H₂O) + CH₄ = (Co⁺ • CH₄ • H₂O)

Enthalpy of reaction

( • ) +  = ( • 2)

By formula: (H₃O⁺ • CH₄) + CH₄ = (H₃O⁺ • 2CH₄)

( • ) +  = ( •  • )

By formula: (Co⁺ • C₂H₆) + CH₄ = (Co⁺ • CH₄ • C₂H₆)

Enthalpy of reaction

 +  = ( • )

By formula: H₄N⁺ + CH₄ = (H₄N⁺ • CH₄)

 (g) +  (cr) =  (g) +  (cr)

By formula: HBr (g) + CH₃Li (cr) = CH₄ (g) + BrLi (cr)

2 +  =  + 2

By formula: 2H₂ + CH₂Cl₂ = CH₄ + 2HCl

 (l) + ( • 100) (solution) = 2 (g) + ( • 100) (solution)

By formula: C₂H₆Zn (l) + (H₂O₄S • 100H₂O) (solution) = 2CH₄ (g) + (O₄SZn • 100H₂O) (solution)

(CH₅⁺ • 4) +  = (CH₅⁺ • 5)

By formula: (CH₅⁺ • 4CH₄) + CH₄ = (CH₅⁺ • 5CH₄)

(CH₅⁺ • 5) +  = (CH₅⁺ • 6)

By formula: (CH₅⁺ • 5CH₄) + CH₄ = (CH₅⁺ • 6CH₄)

(CH₅⁺ • 6) +  = (CH₅⁺ • 7)

By formula: (CH₅⁺ • 6CH₄) + CH₄ = (CH₅⁺ • 7CH₄)

(CH₅⁺ • 7) +  = (CH₅⁺ • 8)

By formula: (CH₅⁺ • 7CH₄) + CH₄ = (CH₅⁺ • 8CH₄)

(C₂H₅⁺ • 2) +  = (C₂H₅⁺ • 3)

By formula: (C₂H₅⁺ • 2CH₄) + CH₄ = (C₂H₅⁺ • 3CH₄)

(C₂H₅⁺ • 3) +  = (C₂H₅⁺ • 4)

By formula: (C₂H₅⁺ • 3CH₄) + CH₄ = (C₂H₅⁺ • 4CH₄)

(C₂H₅⁺ • 4) +  = (C₂H₅⁺ • 5)

By formula: (C₂H₅⁺ • 4CH₄) + CH₄ = (C₂H₅⁺ • 5CH₄)

(C₂H₅⁺ • 5) +  = (C₂H₅⁺ • 6)

By formula: (C₂H₅⁺ • 5CH₄) + CH₄ = (C₂H₅⁺ • 6CH₄)

(C₂H₅⁺ • 6) +  = (C₂H₅⁺ • 7)

By formula: (C₂H₅⁺ • 6CH₄) + CH₄ = (C₂H₅⁺ • 7CH₄)

(C₂H₅⁺ • 7) +  = (C₂H₅⁺ • 8)

By formula: (C₂H₅⁺ • 7CH₄) + CH₄ = (C₂H₅⁺ • 8CH₄)

(C₂H₅⁺ • 8) +  = (C₂H₅⁺ • 9)

By formula: (C₂H₅⁺ • 8CH₄) + CH₄ = (C₂H₅⁺ • 9CH₄)

(C₃H₇⁺ • 2) +  = (C₃H₇⁺ • 3)

By formula: (C₃H₇⁺ • 2CH₄) + CH₄ = (C₃H₇⁺ • 3CH₄)

(C₃H₇⁺ • 3) +  = (C₃H₇⁺ • 4)

By formula: (C₃H₇⁺ • 3CH₄) + CH₄ = (C₃H₇⁺ • 4CH₄)

(C₃H₇⁺ • 4) +  = (C₃H₇⁺ • 5)

By formula: (C₃H₇⁺ • 4CH₄) + CH₄ = (C₃H₇⁺ • 5CH₄)

(C₃H₇⁺ • 5) +  = (C₃H₇⁺ • 6)

By formula: (C₃H₇⁺ • 5CH₄) + CH₄ = (C₃H₇⁺ • 6CH₄)

(C₃H₇⁺ • 6) +  = (C₃H₇⁺ • 7)

By formula: (C₃H₇⁺ • 6CH₄) + CH₄ = (C₃H₇⁺ • 7CH₄)

(C₄H₉⁺ • 2) +  = (C₄H₉⁺ • 3)

By formula: (C₄H₉⁺ • 2CH₄) + CH₄ = (C₄H₉⁺ • 3CH₄)

(C₄H₉⁺ • 3) +  = (C₄H₉⁺ • 4)

By formula: (C₄H₉⁺ • 3CH₄) + CH₄ = (C₄H₉⁺ • 4CH₄)

(C₄H₉⁺ • 4) +  = (C₄H₉⁺ • 5)

By formula: (C₄H₉⁺ • 4CH₄) + CH₄ = (C₄H₉⁺ • 5CH₄)

(C₄H₉⁺ • 5) +  = (C₄H₉⁺ • 6)

By formula: (C₄H₉⁺ • 5CH₄) + CH₄ = (C₄H₉⁺ • 6CH₄)

(C₄H₉⁺ • 6) +  = (C₄H₉⁺ • 7)

By formula: (C₄H₉⁺ • 6CH₄) + CH₄ = (C₄H₉⁺ • 7CH₄)

(C₄H₉⁺ • 7) +  = (C₄H₉⁺ • 8)

By formula: (C₄H₉⁺ • 7CH₄) + CH₄ = (C₄H₉⁺ • 8CH₄)

Vibrational and/or electronic energy levels

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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: Takehiko Shimanouchi

Symmetry:   T_d     Symmetry Number σ = 12

Source: Shimanouchi, 1972

Notes

References

Go To: Top, Reaction thermochemistry data, Vibrational and/or electronic energy levels, Notes

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

Ellison, Engelking, et al., 1978
Ellison, G.B.; Engelking, P.C.; Lineberger, W.C., An experimental determination of the geometry and electron affinity of CH₃, J. Am. Chem. Soc., 1978, 100, 2556. [all data]

Graul and Squires, 1990
Graul, S.T.; Squires, R.R., Gas-Phase Acidities Derived from Threshold Energies for Activated Reactions, J. Am. Chem. Soc., 1990, 112, 7, 2517, https://doi.org/10.1021/ja00163a007 . [all data]

Bohme, Lee-Ruff, et al., 1972
Bohme, D.K.; Lee-Ruff, E.; Young, L.B., Acidity order of selected bronsted acids in the gas phase at 300K, J. Am. Chem. Soc., 1972, 94, 5153. [all data]

Check, Faust, et al., 2001
Check, C.E.; Faust, T.O.; Bailey, J.M.; Wright, B.J.; Gilbert, T.M.; Sunderlin, L.S., Addition of Polarization and Diffuse Functions to the LANL2DZ Basis Set for P-Block Elements, J. Phys. Chem. A,, 2001, 105, 34, 8111, https://doi.org/10.1021/jp011945l . [all data]

Hiraoka and Mori, 1989
Hiraoka, K.; Mori, T., Gas - Phase Stability and Structure of Cluster Ions CH5+(CH4)n with n = 1 - 9, Chem. Phys. Lett., 1989, 161, 2, 111, https://doi.org/10.1016/0009-2614(89)85040-7 . [all data]

Hiraoka and Kebarle, 1975
Hiraoka, K.; Kebarle, P., Energetics, Stabilities and Possible Structures of CH5+(CH4)n Clusters from Gas Phase Study of Equilibria CH5+(CH4)n - 1 + CH4 = CH5+(CH4)n for n = 1 - 5, J. Am. Chem. Soc., 1975, 97, 15, 4179, https://doi.org/10.1021/ja00848a005 . [all data]

Field and Beggs, 1971
Field, F.H.; Beggs, D.P., Reversible Reactions of Gas Phase Ions. III. Studies with Methane at 0.1-1.0 Torr and 77-300 K, J. Am. Chem. Soc., 1971, 93, 7, 1585, https://doi.org/10.1021/ja00736a003 . [all data]

Hiraoka, Mori, et al., 1993
Hiraoka, K.; Mori, T.; Yamabe, S., The Gas-Phase Solvation of C2H5+, s-C3H7+ and s-C4H9+ with CH4. The Isomeric Structures of C2H5+ and C2H5+.CH4, Chem. Phys. Lett., 1993, 207, 2-3, 178, https://doi.org/10.1016/0009-2614(93)87011-Q . [all data]

Hiroka and Kebarle, 1975
Hiroka, K.; Kebarle, P., Information on the Proton Affinity and Protolysis of Propane from Measurement of the Ion Cluster Equilibrium: C2H5+ + CH4 = C3H9+, Can. J. Phys., 1975, 53, 970. [all data]

Kemper, Bushnell, et al., 1993
Kemper, P.R.; Bushnell, J.; Von Koppen, P.; Bowers, M.T., Binding Energies of Co+(H2/CH4/C2H6)1,2,3 Clusters, J. Phys. Chem., 1993, 97, 9, 1810, https://doi.org/10.1021/j100111a016 . [all data]

Armentrout and Kickel, 1994
Armentrout, P.B.; Kickel, B.L., Gas Phase Thermochemistry of Transition Metal Ligand Systems: Reassessment of Values and Periodic Trends, in Organometallic Ion Chemistry, B. S. Freiser, ed, 1994. [all data]

Haynes and Armentrout, 1996
Haynes, C.L.; Armentrout, P.B., Guided Ion Beam Determination of the Co+ - H2 Bond Dissociation energy, Chem Phys. Let., 1996, 249, 1-2, 64, https://doi.org/10.1016/0009-2614(95)01337-7 . [all data]

Kemper, Bushnell, et al., 1993, 2
Kemper, P.R.; Bushnell, J.; Von Helden, G.; Bowers, M.T., Co+(H2)n Clusters: Binding Energies and Molecular Parameters, J. Chem Phys., 1993, 97, 1, 52, https://doi.org/10.1021/j100103a012 . [all data]

Martinho Simões and Beauchamp, 1990
Martinho Simões, J.A.; Beauchamp, J.L., Chem. Rev., 1990, 90, 629. [all data]

Holm, 1981
Holm, T., J. Chem. Soc., Perkin Trans. II, 1981, 464.. [all data]

Pedley, 1994
Pedley, J.B., Thermodynamic Data and Structures of Organic Compounds; Thermodynamics Research Center Data Series, Vol I, Thermodynamics Research Center, College Station, 1994. [all data]

Martin and Finke, 1990
Martin, B.D.; Finke, R.G., J. Am. Chem. Soc., 1990, 112, 2419. [all data]

Martin and Finke, 1992
Martin, B.D.; Finke, R.G., J. Am. Chem. Soc., 1992, 114, 585. [all data]

Hiraoka and Kebarle, 1976
Hiraoka, K.; Kebarle, P., Stabilities and Energetics of Pentacoordinated Carbonium Ions. The Isomeric C2H7+ Ions and Some Higher Analogues: C3H9+ and C4H11+, J. Am. Chem. Soc., 1976, 98, 20, 6119, https://doi.org/10.1021/ja00436a009 . [all data]

Golden, Walsh, et al., 1965
Golden, D.M.; Walsh, R.; Benson, S.W., The thermochemistry of the gas phase equilibrium I₂ + CH₄ «=» CH₃I + HI and the heat of formation of the methyl radical, J. Am. Chem. Soc., 1965, 87, 4053-4057. [all data]

Goy and Pritchard, 1965
Goy, C.A.; Pritchard, H.O., Kinetics and thermodynamics of the reaction between iodine and methane and the heat of formation of methyl iodide, J. Phys. Chem., 1965, 69, 3040-3041. [all data]

Nichol and Ubbelohde, 1952
Nichol, R.J.; Ubbelohde, A.R., A thermochemical evaluation of bond strengths in some carbon compounds. part II. Bond strengths based on the reaction CH₃I + HI = CH₄ + I₂, J. Am. Chem. Soc., 1952, 415-421. [all data]

Bennet and Field, 1972
Bennet, S.L.; Field, F.H., Reversible Reactions of Gaseous Ions. V. The Methane - Water System at Low Temperatures, J. Am. Chem. Soc., 1972, 94, 15, 5188, https://doi.org/10.1021/ja00770a008 . [all data]

Bennet and Field, 1972, 2
Bennet, S.L.; Field, F.H., Reversible Reactions of Gaseous Ions. VI. The NH3 - CH4, H2S - CH4 and CF4 - CH4 Systems at Low Temperatures, J. Am. Chem. Soc., 1972, 94, 18, 6305, https://doi.org/10.1021/ja00773a009 . [all data]

Holm, 1974
Holm, T., J. Organometal. Chem., 1974, 77, 27. [all data]

Pedley and Rylance, 1977
Pedley, J.B.; Rylance, J., Computer Analysed Thermochemical Data: Organic and Organometallic Compounds, University of Sussex, Brigton, 1977. [all data]

Liebman, Martinho Simões, et al., 1995
Liebman, J.F.; Martinho Simões, J.A.; Slayden, S.W., In Lithium Chemistry: A Theoretical and Experimental Overview Wiley: New York, Sapse, A.-M.; Schleyer, P. von Ragué, ed(s)., 1995. [all data]

Lacher, Amador, et al., 1967
Lacher, J.R.; Amador, A.; Park, J.D., Reaction heats of organic compounds. Part 5.-Heats of hydrogenation of dichloromethane, 1,1- and 1,2-dichloroethane and 1,2-dichloropropane, Trans. Faraday Soc., 1967, 63, 1608-1611. [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]

Carson, Hartley, et al., 1949
Carson, A.S.; Hartley, K.; Skinner, H.A., Thermochemistry of metal alkyls. Part II.?The bond dissociation energies of some Zn?C and Cd?C bonds, and of Et?I., Trans. Faraday Soc., 1949, 45, 1159, https://doi.org/10.1039/tf9494501159 . [all data]

Cox and Pilcher, 1970, 2
Cox, J.D.; Pilcher, G., Thermochemistry of Organic and Organometallic Compounds in Academic Press, New York, 1970. [all data]

Shimanouchi, 1972
Shimanouchi, T., Tables of Molecular Vibrational Frequencies Consolidated Volume I, National Bureau of Standards, 1972, 1-160. [all data]

Notes

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• Symbols used in this document:
  

  T	Temperature
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions
  ΔrS°	Entropy of reaction at standard conditions

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