Methane, iodo-

• Formula: CH₃I
• Molecular weight: 141.9390
• IUPAC Standard InChI: InChI=1S/CH3I/c1-2/h1H3 Copy

  
• IUPAC Standard InChIKey: INQOMBQAUSQDDS-UHFFFAOYSA-N Copy
• CAS Registry Number: 74-88-4
• 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:
  • iodo(2H3)methane
• Other names: Iodomethane; Methyl iodide; CH3I; Halon 10001; Iodometano; Iodure de methyle; Jod-methan; Joodmethaan; Methyljodid; Methyljodide; Metylu jodek; Monoioduro di metile; Rcra waste number U138; UN 2644; Methyl iodine; Monoiodomethane; NSC 9366
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Gas phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data
  • Mass spectrum (electron ionization)
  • Gas Chromatography
  • References
  • Notes
• Other data available:
  • Condensed phase thermochemistry data
  • Henry's Law data
  • Gas phase ion energetics data
  • Ion clustering data
  • IR Spectrum
  • Vibrational and/or electronic energy levels
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
  • X-ray Photoelectron Spectroscopy Database, version 5.0
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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 by: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

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
AC - William E. Acree, Jr., James S. Chickos
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

Enthalpy of vaporization

Antoine Equation Parameters

log₁₀(P) = A − (B / (T + C))
    P = vapor pressure (atm)
    T = temperature (K)

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Enthalpy of sublimation

Enthalpy of fusion

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
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
MS - José A. Martinho Simões

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: I^- + CH₃I = (I^- • CH₃I)

C₆H₇N⁺ +  = (C₆H₇N⁺ • )

By formula: C₆H₇N⁺ + CH₃I = (C₆H₇N⁺ • CH₃I)

Free energy of reaction

 +  = ( • )

By formula: Cl^- + CH₃I = (Cl^- • CH₃I)

 +  =  + 

By formula: HI + CH₃I = CH₄ + I₂

C₁₂H₁₆Nb (cr) + 2 (cr) = C₁₀H₁₀I₂Nb (cr) + 2 (l)

By formula: C₁₂H₁₆Nb (cr) + 2I₂ (cr) = C₁₀H₁₀I₂Nb (cr) + 2CH₃I (l)

C₁₄H₂₂CoN₅O₄ (solution) +  (solution) = C₁₃H₁₉CoIN₅O₄ (solution) +  (solution)

By formula: C₁₄H₂₂CoN₅O₄ (solution) + I₂ (solution) = C₁₃H₁₉CoIN₅O₄ (solution) + CH₃I (solution)

CH₃I₂^- + 2 = C₂H₆I₃^-

By formula: CH₃I₂^- + 2CH₃I = C₂H₆I₃^-

 (cr) +  (solution) = CH₃IMg (solution)

By formula: Mg (cr) + CH₃I (solution) = CH₃IMg (solution)

CH₂I^- +  =

By formula: CH₂I^- + H⁺ = CH₃I

 (l) + 2 (cr) = 2 (l) +  (cr)

By formula: C₂H₆Hg (l) + 2I₂ (cr) = 2CH₃I (l) + HgI₂ (cr)

 (l) + 3 (cr) = GaI₃ (cr) + 3 (l)

By formula: C₃H₉Ga (l) + 3I₂ (cr) = GaI₃ (cr) + 3CH₃I (l)

 (l) + 2 (cr) = CH₃GaI₂ (cr) + 2 (l)

By formula: C₃H₉Ga (l) + 2I₂ (cr) = CH₃GaI₂ (cr) + 2CH₃I (l)

C₁₆H₃₄P₂Ru (solution) +  (solution) = C₁₆H₃₃IP₂Ru (solution) +  (solution)

By formula: C₁₆H₃₄P₂Ru (solution) + CH₃I (solution) = C₁₆H₃₃IP₂Ru (solution) + CH₄ (solution)

C₂₂H₃₆Zr (solution) + 2 (solution) = C₂₀H₃₀I₂Zr (solution) + 2 (solution)

By formula: C₂₂H₃₆Zr (solution) + 2I₂ (solution) = C₂₀H₃₀I₂Zr (solution) + 2CH₃I (solution)

C₈H₅MoNaO₃ (solution) +  (l) = C₉H₈MoO₃ (solution) +  (cr)

By formula: C₈H₅MoNaO₃ (solution) + CH₃I (l) = C₉H₈MoO₃ (solution) + INa (cr)

C₁₂H₁₆Zr (solution) + 2 (solution) = C₁₀H₁₀I₂Zr (solution) + 2 (solution)

By formula: C₁₂H₁₆Zr (solution) + 2I₂ (solution) = C₁₀H₁₀I₂Zr (solution) + 2CH₃I (solution)

C₂₂H₃₆Hf (solution) + 2 (solution) = C₂₀H₃₀HfI₂ (solution) + 2 (solution)

By formula: C₂₂H₃₆Hf (solution) + 2I₂ (solution) = C₂₀H₃₀HfI₂ (solution) + 2CH₃I (solution)

 + 2 = 2 + 

By formula: H₂ + 2CH₃I = 2CH₄ + I₂

 +  = 2

By formula: CH₄ + CH₂I₂ = 2CH₃I

Mass spectrum (electron ionization)

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

Spectrum

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Additional Data

Gas Chromatography

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

Kovats' RI, non-polar column, isothermal

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Kovats' RI, polar column, isothermal

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Van Den Dool and Kratz RI, non-polar column, temperature ramp

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Normal alkane RI, non-polar column, custom temperature program

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Normal alkane RI, polar column, custom temperature program

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References

Go To: Top, Gas phase thermochemistry data, Phase change data, Reaction thermochemistry data, Mass spectrum (electron ionization), Gas Chromatography, Notes

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

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]

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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]

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Carson, A.S.; Carter, W.; Pedley, J.B., The thermochemistry of reductions caused by lithium aluminium hydride I. The C-I bond dissociation energy in CH₃I, Proc. Roy. Soc. London A, 1961, 260, 550-557. [all data]

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Wren, D.J.; Vikis, A.C., Vapour pressure of CH3I in the temperature range 176 to 227 K, The Journal of Chemical Thermodynamics, 1982, 14, 5, 435-437, https://doi.org/10.1016/0021-9614(82)90135-5 . [all data]

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Hiraoka, K.; Fujita, K.; Ishida, M.; Ichikawa, T.; Okada, H.; Hiizumi, K.; Wada, A.; Takao, K.; Yamabe, S.; Tsuchida, N., Gas-phase Ion/Molecule Reactions in C5F8, J. Phys. Chem. A (2005), 1905, 109, 6, 1049-1056., https://doi.org/10.1021/jp040251k . [all data]

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Notes

Go To: Top, Gas phase thermochemistry data, Phase change data, Reaction thermochemistry data, Mass spectrum (electron ionization), Gas Chromatography, References

• Symbols used in this document:
  

  T	Temperature
  Tboil	Boiling point
  Tfus	Fusion (melting) point
  ΔfH°gas	Enthalpy of formation of gas at standard conditions
  ΔfusH	Enthalpy of fusion
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions
  ΔrS°	Entropy of reaction at standard conditions
  ΔsubH	Enthalpy of sublimation
  ΔvapH	Enthalpy of vaporization

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