Methane, iodo-
- Formula: CH3I
- Molecular weight: 141.9390
- IUPAC Standard InChIKey: INQOMBQAUSQDDS-UHFFFAOYSA-N
- 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:
- 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
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Condensed phase thermochemistry data
Go To: Top, Reaction thermochemistry 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 |
---|---|---|---|---|---|
ΔfH°liquid | -3.3 ± 0.1 | kcal/mol | Ccr | Carson, Laye, et al., 1993 | ALS |
ΔfH°liquid | -2.9 ± 0.3 | kcal/mol | Chyd | Carson, Carter, et al., 1961 | ALS |
Quantity | Value | Units | Method | Reference | Comment |
ΔcH°liquid | -193.3 ± 0.07 | kcal/mol | Ccr | Carson, Laye, et al., 1993 | ALS |
Constant pressure heat capacity of liquid
Cp,liquid (cal/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
19.78 | 298.15 | Carson, Laye, et al., 1993 | DH |
19.6 | 298.15 | Shehatta, 1993 | DH |
19.78 | 298.2 | Low and Moelwyn-Hughes, 1962 | T = 293 to 308 K.; DH |
19.76 | 300. | Harrison and Moelwyn-Hughes, 1957 | T = 243 to 303 K.; DH |
35.40 | 298. | Kurbatov, 1948 | T = -56 to 35°C. Mean Cp five temperatures.; DH |
Reaction thermochemistry data
Go To: Top, Condensed phase thermochemistry 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:
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)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 8.53 ± 0.20 | kcal/mol | N/A | Van Duzor, Wei, et al., 2010 | gas phase; B |
ΔrH° | 7.80 ± 0.20 | kcal/mol | TDAs | Hiraoka, Fujita, et al., 1905 | gas phase; B |
ΔrH° | 8.40 ± 0.50 | kcal/mol | N/A | Arnold, Neumark, et al., 1995 | gas phase; ZEKE data, shift relative to bare I-; B |
ΔrH° | 8.30 ± 0.50 | kcal/mol | PDis | Cyr, Bishea, et al., 1992 | gas phase; B |
ΔrH° | 9.0 ± 2.0 | kcal/mol | TDAs | Dougherty and Roberts, 1974 | gas phase; B,M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 16.4 | cal/mol*K | HPMS | Dougherty and Roberts, 1974 | gas phase; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 2.73 ± 0.20 | kcal/mol | TDAs | Hiraoka, Fujita, et al., 1905 | gas phase; B |
ΔrG° | 4.10 ± 0.30 | kcal/mol | TDAs | Dougherty and Roberts, 1974 | gas phase; B |
By formula: C6H7N+ + CH3I = (C6H7N+ • CH3I)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 9.7 | kcal/mol | PHPMS | Meot-Ner (Mautner) and El-Shall, 1986 | gas phase; Entropy change calculated or estimated; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 18. | cal/mol*K | N/A | Meot-Ner (Mautner) and El-Shall, 1986 | gas phase; Entropy change calculated or estimated; M |
Free energy of reaction
ΔrG° (kcal/mol) | T (K) | Method | Reference | Comment |
---|---|---|---|---|
4.3 | 299. | PHPMS | Meot-Ner (Mautner) and El-Shall, 1986 | gas phase; Entropy change calculated or estimated; M |
By formula: Cl- + CH3I = (Cl- • CH3I)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 9.80 ± 0.20 | kcal/mol | TDAs | Dougherty and Roberts, 1974 | gas phase; B,M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 7.3 | cal/mol*K | HPMS | Dougherty and Roberts, 1974 | gas phase; Entropy change is questionable; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 7.0 ± 1.3 | kcal/mol | TDAs | Dougherty and Roberts, 1974 | gas phase; B |
By formula: HI + CH3I = CH4 + I2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -12.56 ± 0.13 | kcal/mol | Eqk | Golden, Walsh, et al., 1965 | gas phase; ALS |
ΔrH° | -12.67 ± 0.05 | kcal/mol | Eqk | Goy and Pritchard, 1965 | gas phase; ALS |
ΔrH° | -11.0 ± 1.3 | kcal/mol | Cm | Nichol and Ubbelohde, 1952 | gas phase; ALS |
C12H16Nb (cr) + 2 (cr) = C10H10I2Nb (cr) + 2
(l)
By formula: C12H16Nb (cr) + 2I2 (cr) = C10H10I2Nb (cr) + 2CH3I (l)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -57.91 ± 0.57 | kcal/mol | RSC | Diogo, Simoni, et al., 1993 | The difference between the enthalpies of formation of Nb(Cp)2(I)2 and Nb(Cp)2(Me)2 is calculated as -51.41 ± 0.62 kcal/mol; MS |
C14H22CoN5O4 (solution) + (solution) = C13H19CoIN5O4 (solution) +
(solution)
By formula: C14H22CoN5O4 (solution) + I2 (solution) = C13H19CoIN5O4 (solution) + CH3I (solution)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -22.2 ± 0.60 | kcal/mol | RSC | Toscano, Seligson, et al., 1989 | solvent: Bromoform; The enthalpy of solution of Co(py)(dmg)2(Me)(cr) was measured as 2.61 kcal/mol Toscano, Seligson, et al., 1989; MS |
By formula: CH3I2- + 2CH3I = C2H6I3-
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 7.00 ± 0.20 | kcal/mol | TDAs | Hiraoka, Fujita, et al., 1905 | gas phase; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 1.04 ± 0.20 | kcal/mol | TDAs | Hiraoka, Fujita, et al., 1905 | gas phase; B |
(cr) +
(solution) = CH3IMg (solution)
By formula: Mg (cr) + CH3I (solution) = CH3IMg (solution)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -65.4 ± 0.2 | kcal/mol | RSC | Carson and Skinner, 1950 | solvent: Diethyl ether; It was assumed that MeI(l) has a negligible solution enthalpy in ether; MS |
CH2I- + =
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 386.3 ± 4.9 | kcal/mol | G+TS | Ingemann and Nibbering, 1985 | gas phase; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 379.4 ± 4.8 | kcal/mol | IMRB | Ingemann and Nibbering, 1985 | gas phase; B |
By formula: C2H6Hg (l) + 2I2 (cr) = 2CH3I (l) + HgI2 (cr)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -44.1 ± 0.2 | kcal/mol | RSC | Hartley, Pritchard, et al., 1950 | Please also see Pedley and Rylance, 1977 and Cox and Pilcher, 1970.; MS |
(l) + 3
(cr) = GaI3 (cr) + 3
(l)
By formula: C3H9Ga (l) + 3I2 (cr) = GaI3 (cr) + 3CH3I (l)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -47.8 ± 2.0 | kcal/mol | RSC | Fowell and Mortimer, 1958 | Please also see Pedley and Rylance, 1977 and Cox and Pilcher, 1970.; MS |
(l) + 2
(cr) = CH3GaI2 (cr) + 2
(l)
By formula: C3H9Ga (l) + 2I2 (cr) = CH3GaI2 (cr) + 2CH3I (l)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -37.9 ± 1.0 | kcal/mol | RSC | Fowell and Mortimer, 1958 | Please also see Pedley and Rylance, 1977 and Cox and Pilcher, 1970.; MS |
C16H34P2Ru (solution) + (solution) = C16H33IP2Ru (solution) +
(solution)
By formula: C16H34P2Ru (solution) + CH3I (solution) = C16H33IP2Ru (solution) + CH4 (solution)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -45.00 ± 0.69 | kcal/mol | RSC | Luo, Li, et al., 1995 | solvent: Tetrahydrofuran; MS |
C22H36Zr (solution) + 2 (solution) = C20H30I2Zr (solution) + 2
(solution)
By formula: C22H36Zr (solution) + 2I2 (solution) = C20H30I2Zr (solution) + 2CH3I (solution)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -70.00 ± 0.60 | kcal/mol | RSC | Schock and Marks, 1988 | solvent: Toluene; MS |
C8H5MoNaO3 (solution) + (l) = C9H8MoO3 (solution) +
(cr)
By formula: C8H5MoNaO3 (solution) + CH3I (l) = C9H8MoO3 (solution) + INa (cr)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -7.70 ± 0.31 | kcal/mol | RSC | Nolan, López de la Vega, et al., 1986 | solvent: Tetrahydrofuran; MS |
C12H16Zr (solution) + 2 (solution) = C10H10I2Zr (solution) + 2
(solution)
By formula: C12H16Zr (solution) + 2I2 (solution) = C10H10I2Zr (solution) + 2CH3I (solution)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -69.60 ± 0.60 | kcal/mol | RSC | Schock and Marks, 1988 | solvent: Toluene; MS |
C22H36Hf (solution) + 2 (solution) = C20H30HfI2 (solution) + 2
(solution)
By formula: C22H36Hf (solution) + 2I2 (solution) = C20H30HfI2 (solution) + 2CH3I (solution)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -63.41 ± 0.79 | kcal/mol | RSC | Schock and Marks, 1988 | solvent: Toluene; MS |
By formula: H2 + 2CH3I = 2CH4 + I2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -30.0 ± 0.6 | kcal/mol | Chyd | Carson, Carter, et al., 1961 | liquid phase; solvent: Ether; ALS |
By formula: CH4 + CH2I2 = 2CH3I
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -4.7 ± 1.0 | kcal/mol | Eqk | Furuyama, Golden, et al., 1968 | gas phase; ALS |
Henry's Law 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 compiled by: Rolf Sander
Henry's Law constant (water solution)
kH(T) = k°H exp(d(ln(kH))/d(1/T) ((1/T) - 1/(298.15 K)))
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)
k°H (mol/(kg*bar)) | d(ln(kH))/d(1/T) (K) | Method | Reference | Comment |
---|---|---|---|---|
0.14 | 4300. | M | N/A | |
0.35 | Q | N/A | missing citation give several references for the Henry's law constants but don't assign them to specific species. | |
0.19 | 3800. | M | N/A | |
0.18 | V | N/A | ||
0.17 | C | N/A |
References
Go To: Top, Condensed phase thermochemistry data, Reaction thermochemistry 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.
Carson, Laye, et al., 1993
Carson, A.S.; Laye, P.G.; Pedley, J.B.; Welsby, A.M.,
The enthalpies of formation iodomethane, diiodomethane, triiodomethane, and tetraiodomethane by rotating combustion calorimetry,
J. Chem. Thermodyn., 1993, 25, 261-269. [all data]
Carson, Carter, et al., 1961
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]
Shehatta, 1993
Shehatta, I.,
Heat capacity at constant pressure of some halogen compounds,
Thermochim. Acta, 1993, 213, 1-10. [all data]
Low and Moelwyn-Hughes, 1962
Low, D.I.R.; Moelwyn-Hughes, E.A.,
The heat capacities of acetone, methyl iodide and mixtures thereof in the liquid state,
Proc. Roy. Soc. (London), 1962, A267, 384-394. [all data]
Harrison and Moelwyn-Hughes, 1957
Harrison, D.; Moelwyn-Hughes, E.A.,
The heat capacities of certain liquids,
Proc. Roy. Soc. (London), 1957, A239, 230-246. [all data]
Kurbatov, 1948
Kurbatov, V.Ya.,
Heat capacity of liquids. 2. Heat capacity and the temperature dependence of heat capacity from halogen derivatives of acylic hydrocarbons,
Zh. Obshch. Kim., 1948, 18, 372-389. [all data]
Van Duzor, Wei, et al., 2010
Van Duzor, M.; Wei, J.; Mbaiwa, F.; Mabbs, R.,
I-center dot CH3X (X=Cl, Br, I) photodetachment: The effect of electron-molecule interactions in cluster anion photodetachment spectra and angular distributions,
J. Chem. Phys., 2010, 133, 14, 144303, https://doi.org/10.1063/1.3487739
. [all data]
Hiraoka, Fujita, et al., 1905
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]
Arnold, Neumark, et al., 1995
Arnold, C.C.; Neumark, D.M.; Cyr, D.M.; Johnson, M.A.,
Negative ion zero electron kinetic energy spectroscopy of I-center dot CH3I,
J. Phys. Chem., 1995, 99, 6, 1633, https://doi.org/10.1021/j100006a002
. [all data]
Cyr, Bishea, et al., 1992
Cyr, D.M.; Bishea, G.A.; Scarton, M.G.; Johnson, M.A.,
Observation of Charge-Transfer Excited States in the I-.CH3I, I-.CH3Br, and I-.CH2Br2 S(N)2 Reaction Intermediates Using Photofragmentation,
J. Chem. Phys., 1992, 97, 8, 5911, https://doi.org/10.1063/1.463752
. [all data]
Dougherty and Roberts, 1974
Dougherty, R.C.; Roberts, J.D.,
SN2 reactions in the gas phase. Nucleophilicity effects,
Org. Mass Spectrom., 1974, 8, 81. [all data]
Meot-Ner (Mautner) and El-Shall, 1986
Meot-Ner (Mautner), M.; El-Shall, M.S.,
Ionic Charge Transfer Complexes. 1. Cationic Complexes with Delocalized and Partially Localized pi Systems,
J. Am. Chem. Soc., 1986, 108, 15, 4386, https://doi.org/10.1021/ja00275a026
. [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]
Diogo, Simoni, et al., 1993
Diogo, H.P.; Simoni, J.A.; Minas da Piedade, M.E.; Dias, A.R.; Martinho Simões, J.A.,
J. Am. Chem. Soc., 1993, 115, 2764. [all data]
Toscano, Seligson, et al., 1989
Toscano, P.J.; Seligson, A.L.; Curran, M.T.; Skrobutt, A.T.; Sonnenberger, D.C.,
Inorg. Chem., 1989, 28, 166; ibid. 1989. [all data]
Carson and Skinner, 1950
Carson, A.S.; Skinner, H.A.,
Nature, 1950, 165, 484. [all data]
Ingemann and Nibbering, 1985
Ingemann, S.; Nibbering, N.M.M.,
Gas-phase acidity of CH3X [X = P(CH3)2, SCH3, F, Cl, Br, I] compounds,
J. Chem. Soc. Perkin Trans. 2, 1985, 837. [all data]
Hartley, Pritchard, et al., 1950
Hartley, K.; Pritchard, H.O.; Skinner, H.A.,
Thermochemistry of metallic alkyls. III.?mercury dimethyl and mercury methyl halides,
Trans. Faraday Soc., 1950, 46, 1019, https://doi.org/10.1039/tf9504601019
. [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]
Cox and Pilcher, 1970
Cox, J.D.; Pilcher, G.,
Thermochemistry of Organic and Organometallic Compounds
in Academic Press, New York, 1970. [all data]
Fowell and Mortimer, 1958
Fowell, P.A.; Mortimer, C.T.,
J. Chem. Soc., 1958, 3734.. [all data]
Luo, Li, et al., 1995
Luo, L.; Li, C.; Cucullu, M.E.; Nolan, S.P.,
Organometallics, 1995, 14, 1333. [all data]
Schock and Marks, 1988
Schock, L.E.; Marks, T.J.,
J. Am. Chem. Soc., 1988, 110, 7701. [all data]
Nolan, López de la Vega, et al., 1986
Nolan, S.P.; López de la Vega, R.; Hoff, C.D.,
J. Organometal. Chem., 1986, 315, 187. [all data]
Furuyama, Golden, et al., 1968
Furuyama, S.; Golden, D.M.; Benson, S.W.,
The thermochemistry of the gas-phase equilibrium 2CH3I = CH4 + CH2i2. The heat of formation of CH2I2,
J. Phys. Chem., 1968, 72, 4713-4715. [all data]
Notes
Go To: Top, Condensed phase thermochemistry data, Reaction thermochemistry data, Henry's Law data, References
- Symbols used in this document:
Cp,liquid Constant pressure heat capacity of liquid T Temperature d(ln(kH))/d(1/T) Temperature dependence parameter for Henry's Law constant k°H Henry's Law constant at 298.15K ΔcH°liquid Enthalpy of combustion of liquid at standard conditions ΔfH°liquid Enthalpy of formation of liquid at standard conditions ΔrG° Free energy of reaction at standard conditions ΔrH° Enthalpy of reaction at standard conditions ΔrS° Entropy of reaction at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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