Methane

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Gas phase thermochemistry data

Go To: Top, Reaction thermochemistry data, Henry's Law data, Vibrational and/or electronic energy levels, 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-17.89kcal/molReviewChase, 1998Data last reviewed in March, 1961
Δfgas-17.8 ± 0.07kcal/molReviewManion, 2002adopted recommendation of Gurvich, Veyts, et al., 1991; DRB
Δfgas-17.8 ± 0.1kcal/molCcbPittam and Pilcher, 1972ALS
Δfgas-17.889 ± 0.075kcal/molCcbProsen and Rossini, 1945Hf derived from Heat of Hydrogenation; ALS
Δfgas-17.54 ± 0.26kcal/molCcbRoth and Banse, 1932Reanalyzed by Cox and Pilcher, 1970, Original value = -17.97 kcal/mol; ALS
Quantity Value Units Method Reference Comment
Δcgas-212.88 ± 0.09kcal/molCcbPittam and Pilcher, 1972Corresponding Δfgas = -17.80 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS
Δcgas-212.798 ± 0.072kcal/molCcbProsen and Rossini, 1945Hf derived from Heat of Hydrogenation; Corresponding Δfgas = -17.883 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS
Δcgas-213.14 ± 0.26kcal/molCcbRoth and Banse, 1932Reanalyzed by Cox and Pilcher, 1970, Original value = -212.07 ± 0.25 kcal/mol; Corresponding Δfgas = -17.54 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS
Δcgas-212.753 ± 0.072kcal/molCmRossini, 1931Corresponding Δfgas = -17.928 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS
Quantity Value Units Method Reference Comment
gas45.09 ± 0.10cal/mol*KN/AColwell J.H., 1963The calorimetric value is significantly higher than the statistically calculated entropy, 186.26 J/mol*K, which remains the best value for use in thermodynamic calculations [ Vogt G.J., 1976, Friend D.G., 1989, Gurvich, Veyts, et al., 1989]. Earlier the value of 185.3 J/mol*K was calculated from experimental data [ Giauque W.F., 1931]. The value of S(298.15 K)=185.94 J/mol*K was obtained by high accuracy ab initio calculation [ East A.L.L., 1997].; GT
Quantity Value Units Method Reference Comment
gas,1 bar44.515cal/mol*KReviewChase, 1998Data last reviewed in March, 1961

Constant pressure heat capacity of gas

Cp,gas (cal/mol*K) Temperature (K) Reference Comment
8.346 ± 0.060279.Halford J.O., 1957GT

Constant pressure heat capacity of gas

Cp,gas (cal/mol*K) Temperature (K) Reference Comment
7.954100.Gurvich, Veyts, et al., 1989p=1 bar. Because of more precise method of calculation, the recommended values are more accurate, especially at high temperatures, than those obtained by [ McDowell R.S., 1963] and often regarded as reference data [ Friend D.G., 1989].; GT
8.009200.
8.530298.15
8.547300.
9.711400.
11.14500.
12.61600.
14.01700.
15.32800.
16.52900.
17.631000.
18.621100.
19.521200.
20.331300.
21.061400.
21.721500.
22.311600.
22.841700.
23.331800.
23.781900.
24.1972000.
24.5772100.
24.9312200.
25.2632300.
25.5742400.
25.8682500.
26.1452600.
26.4102700.
26.6632800.
26.9052900.
27.1393000.

Gas Phase Heat Capacity (Shomate Equation)

Cp° = A + B*t + C*t2 + D*t3 + E/t2
H° − H°298.15= A*t + B*t2/2 + C*t3/3 + D*t4/4 − E/t + F − H
S° = A*ln(t) + B*t + C*t2/2 + D*t3/3 − E/(2*t2) + G
    Cp = heat capacity (cal/mol*K)
    H° = standard enthalpy (kcal/mol)
    S° = standard entropy (cal/mol*K)
    t = temperature (K) / 1000.

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Temperature (K) 298. to 1300.1300. to 6000.
A -0.16802820.50960
B 25.926702.692321
C -10.16290-0.505293
D 1.4012400.033028
E 0.162181-6.315060
F -18.36610-36.69520
G 37.9341153.63631
H -17.89510-17.89510
ReferenceChase, 1998Chase, 1998
Comment Data last reviewed in March, 1961 Data last reviewed in March, 1961

Reaction thermochemistry data

Go To: Top, Gas phase thermochemistry data, Henry's Law data, Vibrational and/or electronic energy levels, 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
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- + Hydrogen cation = Methane

By formula: CH3- + H+ = CH4

Quantity Value Units Method Reference Comment
Δr416.74 ± 0.70kcal/molD-EAEllison, Engelking, et al., 1978gas phase; B
Δr418.0 ± 3.5kcal/molCIDTGraul and Squires, 1990gas phase; B
Δr>404.18 ± 0.10kcal/molG+TSBohme, Lee-Ruff, et al., 1972gas phase; B
Δr414.80kcal/molN/ACheck, Faust, et al., 2001gas phase; FeBr3; ; ΔS(EA)=9.3; B
Quantity Value Units Method Reference Comment
Δr408.66 ± 0.80kcal/molH-TSEllison, Engelking, et al., 1978gas phase; B
Δr409.9 ± 3.6kcal/molH-TSGraul and Squires, 1990gas phase; B
Δr>396.10kcal/molIMRBBohme, Lee-Ruff, et al., 1972gas phase; B
Δr407.30kcal/molN/ACheck, Faust, et al., 2001gas phase; FeBr3; ; ΔS(EA)=9.3; B

(CH5+ • Methane) + Methane = (CH5+ • 2Methane)

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

Quantity Value Units Method Reference Comment
Δr5.3 ± 0.3kcal/molPHPMSHiraoka and Mori, 1989gas phase; M
Δr5.9kcal/molPHPMSHiraoka and Kebarle, 1975gas phase; M
Δr1.5kcal/molHPMSField and Beggs, 1971gas phase; Entropy change is questionable; M
Quantity Value Units Method Reference Comment
Δr24.9cal/mol*KPHPMSHiraoka and Mori, 1989gas phase; M
Δr24.4cal/mol*KPHPMSHiraoka and Kebarle, 1975gas phase; M
Δr7.2cal/mol*KHPMSField and Beggs, 1971gas phase; Entropy change is questionable; M

CH5+ + Methane = (CH5+ • Methane)

By formula: CH5+ + CH4 = (CH5+ • CH4)

Quantity Value Units Method Reference Comment
Δr6.9 ± 0.3kcal/molPHPMSHiraoka and Mori, 1989gas phase; M
Δr7.4kcal/molPHPMSHiraoka and Kebarle, 1975gas phase; M
Δr4.1kcal/molHPMSField and Beggs, 1971gas phase; Entropy change is questionable; M
Quantity Value Units Method Reference Comment
Δr22.1cal/mol*KPHPMSHiraoka and Mori, 1989gas phase; M
Δr20.8cal/mol*KPHPMSHiraoka and Kebarle, 1975gas phase; M
Δr12.4cal/mol*KHPMSField and Beggs, 1971gas phase; Entropy change is questionable; M

C2H5+ + Methane = (C2H5+ • Methane)

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

Quantity Value Units Method Reference Comment
Δr5.50kcal/molPHPMSHiraoka, Mori, et al., 1993gas phase; M
Δr6.6kcal/molPHPMSHiroka and Kebarle, 1975gas phase; M
Δr2.4kcal/molHPMSField and Beggs, 1971gas phase; Entropy change is questionable; M
Quantity Value Units Method Reference Comment
Δr22.2cal/mol*KPHPMSHiraoka, Mori, et al., 1993gas phase; M
Δr23.4cal/mol*KPHPMSHiroka and Kebarle, 1975gas phase; M
Δr8.6cal/mol*KHPMSField and Beggs, 1971gas phase; Entropy change is questionable; M

(Cobalt ion (1+) • 2Methane) + Methane = (Cobalt ion (1+) • 3Methane)

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

Quantity Value Units Method Reference Comment
Δr11.kcal/molSIDTKemper, Bushnell, et al., 1993gas phase; Entropy change calculated or estimated; M
Quantity Value Units Method Reference Comment
Δr20.cal/mol*KN/AKemper, Bushnell, et al., 1993gas phase; Entropy change calculated or estimated; M

Enthalpy of reaction

ΔrH° (kcal/mol) T (K) Method Reference Comment
9.8 (+1.2,-0.) CIDArmentrout and Kickel, 1994gas phase; guided ion beam CID; M

Free energy of reaction

ΔrG° (kcal/mol) T (K) Method Reference Comment
0.7477.SIDTKemper, Bushnell, et al., 1993gas phase; Entropy change calculated or estimated; M

Cobalt ion (1+) + Methane = (Cobalt ion (1+) • Methane)

By formula: Co+ + CH4 = (Co+ • CH4)

Quantity Value Units Method Reference Comment
Δr19.8cal/mol*KSIDTKemper, Bushnell, et al., 1993gas phase; ΔrS(530 K); M

Enthalpy of reaction

ΔrH° (kcal/mol) T (K) Method Reference Comment
21.5 (+1.6,-0.) CIDHaynes and Armentrout, 1996gas phase; guided ion beam CID; M
21.5 (+1.4,-0.) CIDArmentrout and Kickel, 1994gas phase; guided ion beam CID; M
22.5 (+0.5,-0.) SIDTKemper, Bushnell, et al., 1993gas phase; ΔrS(530 K); M

(Cobalt ion (1+) • Methane) + Hydrogen = (Cobalt ion (1+) • Hydrogen • Methane)

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

Quantity Value Units Method Reference Comment
Δr22.9cal/mol*KSIDTKemper, Bushnell, et al., 1993gas phase; switching reaction(Co+).2H2, ΔrS(440 K); Kemper, Bushnell, et al., 1993, 2; M

Enthalpy of reaction

ΔrH° (kcal/mol) T (K) Method Reference Comment
17.4 (+0.8,-0.) SIDTKemper, Bushnell, et al., 1993gas phase; switching reaction(Co+).2H2, ΔrS(440 K); Kemper, Bushnell, et al., 1993, 2; M

(Cobalt ion (1+) • Hydrogen) + Methane = (Cobalt ion (1+) • Methane • Hydrogen)

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

Quantity Value Units Method Reference Comment
Δr21.8cal/mol*KSIDTKemper, Bushnell, et al., 1993gas phase; switching reaction(Co+)2H2, ΔrS(440 K); Kemper, Bushnell, et al., 1993, 2; M

Enthalpy of reaction

ΔrH° (kcal/mol) T (K) Method Reference Comment
22.6 (+1.2,-0.) SIDTKemper, Bushnell, et al., 1993gas phase; switching reaction(Co+)2H2, ΔrS(440 K); Kemper, Bushnell, et al., 1993, 2; M

Manganese, pentacarbonylmethyl- (g) = C5MnO5 (g) + Methane (g)

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

Quantity Value Units Method Reference Comment
Δr45.9 ± 3.6kcal/molPIMSMartinho Simões and Beauchamp, 1990The reaction enthalpy was derived from the appearance energy of Mn(CO)5(+), 224.8 ± 1.1 kcal/mol, using Mn(CO)5(Me) as the neutral precursor, together with the adiabatic ionization energy of Mn(CO)5 radical, 179. ± 3.3 kcal/mol Martinho Simões and Beauchamp, 1990; MS

(Cobalt ion (1+) • Methane) + Methane = (Cobalt ion (1+) • 2Methane)

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

Quantity Value Units Method Reference Comment
Δr26.1cal/mol*KSIDTKemper, Bushnell, et al., 1993gas phase; ΔrS(500 K); M

Enthalpy of reaction

ΔrH° (kcal/mol) T (K) Method Reference Comment
22.9 (+1.2,-0.) CIDArmentrout and Kickel, 1994gas phase; guided ion beam CID; M
24.8 (+1.0,-0.) SIDTKemper, Bushnell, et al., 1993gas phase; ΔrS(500 K); M

(CH5+ • 2Methane) + Methane = (CH5+ • 3Methane)

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

Quantity Value Units Method Reference Comment
Δr3.1 ± 0.2kcal/molPHPMSHiraoka and Mori, 1989gas phase; M
Δr4.1kcal/molPHPMSHiraoka and Kebarle, 1975gas phase; M
Quantity Value Units Method Reference Comment
Δr22.4cal/mol*KPHPMSHiraoka and Mori, 1989gas phase; M
Δr26.1cal/mol*KPHPMSHiraoka and Kebarle, 1975gas phase; M

(CH5+ • 3Methane) + Methane = (CH5+ • 4Methane)

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

Quantity Value Units Method Reference Comment
Δr3.0 ± 0.2kcal/molPHPMSHiraoka and Mori, 1989gas phase; M
Δr3.9kcal/molPHPMSHiraoka and Kebarle, 1975gas phase; M
Quantity Value Units Method Reference Comment
Δr23.7cal/mol*KPHPMSHiraoka and Mori, 1989gas phase; M
Δr26.6cal/mol*KPHPMSHiraoka and Kebarle, 1975gas phase; M

Hydrogen bromide (g) + CH3BrMg (solution) = Methane (solution) + Br2Mg (solution)

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

Quantity Value Units Method Reference Comment
Δr-65.61 ± 0.53kcal/molRSCHolm, 1981solvent: Diethyl ether; The enthalpy of formation was calculated using the assumptions and the auxiliary data in Holm, 1981, except for the organic compound, whose enthalpy of formation was quoted from Pedley, 1994; MS

(Cobalt ion (1+) • Methane) + Ethane = (Cobalt ion (1+) • Ethane • Methane)

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

Quantity Value Units Method Reference Comment
Δr25.9cal/mol*KSIDTKemper, Bushnell, et al., 1993gas phase; switching reaction(Co+).2CH4, ΔrS(480 K); M

Enthalpy of reaction

ΔrH° (kcal/mol) T (K) Method Reference Comment
28.4 (+1.3,-0.) SIDTKemper, Bushnell, et al., 1993gas phase; switching reaction(Co+).2CH4, ΔrS(480 K); M

C63H91CoN13O14P (solution) = Cyanocobalamin (solution) + Methane (solution)

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

Quantity Value Units Method Reference Comment
Δr37.0 ± 3.1kcal/molKinSMartin and Finke, 1990solvent: Ethylene glycol; Please also see Martin and Finke, 1992. The reaction enthalpy relies on 41.0 ± 3.0 kcal/mol for the reaction activation enthalpy. The reaction refers to "base-on" cobalamine.; MS

C3H7+ + Methane = (C3H7+ • Methane)

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

Quantity Value Units Method Reference Comment
Δr2.59kcal/molPHPMSHiraoka, Mori, et al., 1993gas phase; M
Δr3.4kcal/molPHPMSHiraoka and Kebarle, 1976gas phase; M
Quantity Value Units Method Reference Comment
Δr17.4cal/mol*KPHPMSHiraoka, Mori, et al., 1993gas phase; M
Δr20.cal/mol*KPHPMSHiraoka and Kebarle, 1976gas phase; M

Hydrogen iodide + Methane, iodo- = Methane + Iodine

By formula: HI + CH3I = CH4 + I2

Quantity Value Units Method Reference Comment
Δr-12.56 ± 0.13kcal/molEqkGolden, Walsh, et al., 1965gas phase; ALS
Δr-12.67 ± 0.05kcal/molEqkGoy and Pritchard, 1965gas phase; ALS
Δr-11.0 ± 1.3kcal/molCmNichol and Ubbelohde, 1952gas phase; ALS

(C2H5+ • 9Methane) + Methane = (C2H5+ • 10Methane)

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

Quantity Value Units Method Reference Comment
Δr1.91kcal/molPHPMSHiraoka, Mori, et al., 1993gas phase; Entropy change calculated or estimated; M
Quantity Value Units Method Reference Comment
Δr22.cal/mol*KN/AHiraoka, Mori, et al., 1993gas phase; Entropy change calculated or estimated; M

(C3H7+ • 7Methane) + Methane = (C3H7+ • 8Methane)

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

Quantity Value Units Method Reference Comment
Δr1.98kcal/molPHPMSHiraoka, Mori, et al., 1993gas phase; Entropy change calculated or estimated; M
Quantity Value Units Method Reference Comment
Δr22.cal/mol*KN/AHiraoka, Mori, et al., 1993gas phase; Entropy change calculated or estimated; M

(C4H9+ • 8Methane) + Methane = (C4H9+ • 9Methane)

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

Quantity Value Units Method Reference Comment
Δr1.86kcal/molPHPMSHiraoka, Mori, et al., 1993gas phase; Entropy change calculated or estimated; M
Quantity Value Units Method Reference Comment
Δr20.cal/mol*KN/AHiraoka, Mori, et al., 1993gas phase; Entropy change calculated or estimated; M

(CH5+ • 8Methane) + Methane = (CH5+ • 9Methane)

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

Quantity Value Units Method Reference Comment
Δr1.54kcal/molPHPMSHiraoka and Mori, 1989gas phase; Entropy change calculated or estimated; M
Quantity Value Units Method Reference Comment
Δr20.cal/mol*KN/AHiraoka and Mori, 1989gas phase; Entropy change calculated or estimated; M

(Cobalt ion (1+) • Water) + Methane = (Cobalt ion (1+) • Methane • Water)

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

Quantity Value Units Method Reference Comment
Δr27.0cal/mol*KSIDTKemper, Bushnell, et al., 1993gas phase; ΔrS(525 K); M

Enthalpy of reaction

ΔrH° (kcal/mol) T (K) Method Reference Comment
25.9 (+0.7,-0.) SIDTKemper, Bushnell, et al., 1993gas phase; ΔrS(525 K); M

(Hydronium cation • Methane) + Methane = (Hydronium cation • 2Methane)

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

Quantity Value Units Method Reference Comment
Δr3.4kcal/molHPMSBennet and Field, 1972gas phase; Entropy change is questionable; M
Quantity Value Units Method Reference Comment
Δr8.1cal/mol*KHPMSBennet and Field, 1972gas phase; Entropy change is questionable; M

(Cobalt ion (1+) • Ethane) + Methane = (Cobalt ion (1+) • Methane • Ethane)

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

Quantity Value Units Method Reference Comment
Δr26.4cal/mol*KSIDTKemper, Bushnell, et al., 1993gas phase; ΔrS(490 K); M

Enthalpy of reaction

ΔrH° (kcal/mol) T (K) Method Reference Comment
24.4 (+1.1,-0.) SIDTKemper, Bushnell, et al., 1993gas phase; ΔrS(490 K); M

NH4+ + Methane = (NH4+ • Methane)

By formula: H4N+ + CH4 = (H4N+ • CH4)

Quantity Value Units Method Reference Comment
Δr3.6kcal/molHPMSBennet and Field, 1972, 2gas phase; Entropy change is questionable; M
Quantity Value Units Method Reference Comment
Δr15.5cal/mol*KHPMSBennet and Field, 1972, 2gas phase; Entropy change is questionable; M

Hydrogen bromide (g) + methyllithium (cr) = Methane (g) + Lithium bromide (cr)

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

Quantity Value Units Method Reference Comment
Δr-75.84 ± 0.48kcal/molRSCHolm, 1974Please also see Pedley and Rylance, 1977. The reaction enthalpy was quoted from Pedley and Rylance, 1977. See Liebman, Martinho Simões, et al., 1995 for comments; MS

2Hydrogen + Methylene chloride = Methane + 2Hydrogen chloride

By formula: 2H2 + CH2Cl2 = CH4 + 2HCl

Quantity Value Units Method Reference Comment
Δr-39.05 ± 0.30kcal/molChydLacher, Amador, et al., 1967gas phase; Reanalyzed by Cox and Pilcher, 1970, Original value = -40.07 ± 0.30 kcal/mol; At 250 C; ALS

Dimethylzinc (l) + (Sulfuric Acid • 100Water) (solution) = 2Methane (g) + (zinc sulphate • 100Water) (solution)

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

Quantity Value Units Method Reference Comment
Δr-81.7 ± 0.2kcal/molRSCCarson, Hartley, et al., 1949Please also see Pedley and Rylance, 1977 and Cox and Pilcher, 1970, 2.; MS

(CH5+ • 4Methane) + Methane = (CH5+ • 5Methane)

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

Quantity Value Units Method Reference Comment
Δr2.8 ± 0.2kcal/molPHPMSHiraoka and Mori, 1989gas phase; M
Quantity Value Units Method Reference Comment
Δr24.8cal/mol*KPHPMSHiraoka and Mori, 1989gas phase; M

(CH5+ • 5Methane) + Methane = (CH5+ • 6Methane)

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

Quantity Value Units Method Reference Comment
Δr2.7 ± 0.2kcal/molPHPMSHiraoka and Mori, 1989gas phase; M
Quantity Value Units Method Reference Comment
Δr25.3cal/mol*KPHPMSHiraoka and Mori, 1989gas phase; M

(CH5+ • 6Methane) + Methane = (CH5+ • 7Methane)

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

Quantity Value Units Method Reference Comment
Δr2.7 ± 0.2kcal/molPHPMSHiraoka and Mori, 1989gas phase; M
Quantity Value Units Method Reference Comment
Δr26.5cal/mol*KPHPMSHiraoka and Mori, 1989gas phase; M

(CH5+ • 7Methane) + Methane = (CH5+ • 8Methane)

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

Quantity Value Units Method Reference Comment
Δr2.0 ± 0.2kcal/molPHPMSHiraoka and Mori, 1989gas phase; M
Quantity Value Units Method Reference Comment
Δr21.6cal/mol*KPHPMSHiraoka and Mori, 1989gas phase; M

(C2H5+ • 2Methane) + Methane = (C2H5+ • 3Methane)

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

Quantity Value Units Method Reference Comment
Δr2.28kcal/molPHPMSHiraoka, Mori, et al., 1993gas phase; M
Quantity Value Units Method Reference Comment
Δr17.9cal/mol*KPHPMSHiraoka, Mori, et al., 1993gas phase; M

(C2H5+ • 3Methane) + Methane = (C2H5+ • 4Methane)

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

Quantity Value Units Method Reference Comment
Δr2.26kcal/molPHPMSHiraoka, Mori, et al., 1993gas phase; M
Quantity Value Units Method Reference Comment
Δr18.4cal/mol*KPHPMSHiraoka, Mori, et al., 1993gas phase; M

(C2H5+ • 4Methane) + Methane = (C2H5+ • 5Methane)

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

Quantity Value Units Method Reference Comment
Δr2.22kcal/molPHPMSHiraoka, Mori, et al., 1993gas phase; M
Quantity Value Units Method Reference Comment
Δr18.9cal/mol*KPHPMSHiraoka, Mori, et al., 1993gas phase; M

(C2H5+ • 5Methane) + Methane = (C2H5+ • 6Methane)

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

Quantity Value Units Method Reference Comment
Δr2.21kcal/molPHPMSHiraoka, Mori, et al., 1993gas phase; M
Quantity Value Units Method Reference Comment
Δr19.4cal/mol*KPHPMSHiraoka, Mori, et al., 1993gas phase; M

(C2H5+ • 6Methane) + Methane = (C2H5+ • 7Methane)

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

Quantity Value Units Method Reference Comment
Δr2.13kcal/molPHPMSHiraoka, Mori, et al., 1993gas phase; M
Quantity Value Units Method Reference Comment
Δr20.7cal/mol*KPHPMSHiraoka, Mori, et al., 1993gas phase; M

(C2H5+ • 7Methane) + Methane = (C2H5+ • 8Methane)

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

Quantity Value Units Method Reference Comment
Δr2.10kcal/molPHPMSHiraoka, Mori, et al., 1993gas phase; M
Quantity Value Units Method Reference Comment
Δr21.0cal/mol*KPHPMSHiraoka, Mori, et al., 1993gas phase; M

(C2H5+ • 8Methane) + Methane = (C2H5+ • 9Methane)

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

Quantity Value Units Method Reference Comment
Δr2.08kcal/molPHPMSHiraoka, Mori, et al., 1993gas phase; M
Quantity Value Units Method Reference Comment
Δr21.8cal/mol*KPHPMSHiraoka, Mori, et al., 1993gas phase; M

(C3H7+ • 2Methane) + Methane = (C3H7+ • 3Methane)

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

Quantity Value Units Method Reference Comment
Δr2.26kcal/molPHPMSHiraoka, Mori, et al., 1993gas phase; M
Quantity Value Units Method Reference Comment
Δr18.4cal/mol*KPHPMSHiraoka, Mori, et al., 1993gas phase; M

(C3H7+ • 3Methane) + Methane = (C3H7+ • 4Methane)

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

Quantity Value Units Method Reference Comment
Δr2.20kcal/molPHPMSHiraoka, Mori, et al., 1993gas phase; M
Quantity Value Units Method Reference Comment
Δr19.0cal/mol*KPHPMSHiraoka, Mori, et al., 1993gas phase; M

(C3H7+ • 4Methane) + Methane = (C3H7+ • 5Methane)

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

Quantity Value Units Method Reference Comment
Δr2.20kcal/molPHPMSHiraoka, Mori, et al., 1993gas phase; M
Quantity Value Units Method Reference Comment
Δr20.9cal/mol*KPHPMSHiraoka, Mori, et al., 1993gas phase; M

(C3H7+ • 5Methane) + Methane = (C3H7+ • 6Methane)

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

Quantity Value Units Method Reference Comment
Δr2.19kcal/molPHPMSHiraoka, Mori, et al., 1993gas phase; M
Quantity Value Units Method Reference Comment
Δr21.0cal/mol*KPHPMSHiraoka, Mori, et al., 1993gas phase; M

(C3H7+ • 6Methane) + Methane = (C3H7+ • 7Methane)

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

Quantity Value Units Method Reference Comment
Δr2.16kcal/molPHPMSHiraoka, Mori, et al., 1993gas phase; M
Quantity Value Units Method Reference Comment
Δr21.8cal/mol*KPHPMSHiraoka, Mori, et al., 1993gas phase; M

(C4H9+ • 2Methane) + Methane = (C4H9+ • 3Methane)

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

Quantity Value Units Method Reference Comment
Δr2.37kcal/molPHPMSHiraoka, Mori, et al., 1993gas phase; M
Quantity Value Units Method Reference Comment
Δr19.7cal/mol*KPHPMSHiraoka, Mori, et al., 1993gas phase; M

(C4H9+ • 3Methane) + Methane = (C4H9+ • 4Methane)

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

Quantity Value Units Method Reference Comment
Δr2.36kcal/molPHPMSHiraoka, Mori, et al., 1993gas phase; M
Quantity Value Units Method Reference Comment
Δr20.0cal/mol*KPHPMSHiraoka, Mori, et al., 1993gas phase; M

(C4H9+ • 4Methane) + Methane = (C4H9+ • 5Methane)

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

Quantity Value Units Method Reference Comment
Δr2.21kcal/molPHPMSHiraoka, Mori, et al., 1993gas phase; M
Quantity Value Units Method Reference Comment
Δr19.4cal/mol*KPHPMSHiraoka, Mori, et al., 1993gas phase; M

(C4H9+ • 5Methane) + Methane = (C4H9+ • 6Methane)

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

Quantity Value Units Method Reference Comment
Δr2.09kcal/molPHPMSHiraoka, Mori, et al., 1993gas phase; M
Quantity Value Units Method Reference Comment
Δr19.3cal/mol*KPHPMSHiraoka, Mori, et al., 1993gas phase; M

(C4H9+ • 6Methane) + Methane = (C4H9+ • 7Methane)

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

Quantity Value Units Method Reference Comment
Δr2.05kcal/molPHPMSHiraoka, Mori, et al., 1993gas phase; M
Quantity Value Units Method Reference Comment
Δr19.7cal/mol*KPHPMSHiraoka, Mori, et al., 1993gas phase; M

(C4H9+ • 7Methane) + Methane = (C4H9+ • 8Methane)

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

Quantity Value Units Method Reference Comment
Δr1.99kcal/molPHPMSHiraoka, Mori, et al., 1993gas phase; M
Quantity Value Units Method Reference Comment
Δr20.1cal/mol*KPHPMSHiraoka, Mori, et al., 1993gas phase; M

Henry's Law 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: 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
0.00141600.LN/AThe parameterization given by missing citation (parameters A, B, C) doesn't fit the data in the same paper for this substance. Therefore the parameteriztaion of the solubility data (X1) was recalculated.
0.00131900.QN/AOnly the tabulated data between T = 273. K and T = 303. K from missing citation was used to derive kH and -Δ kH/R. Above T = 303. K the tabulated data could not be parameterized by equation (reference missing) very well. The partial pressure of water vapor (needed to convert some Henry's law constants) was calculated using the formula given by missing citation. The quantities A and α from missing citation were assumed to be identical.
0.0015 QN/A missing citation give several references for the Henry's law constants but don't assign them to specific species.
0.0013 LN/A 
0.00131800.XN/A 
0.00141700.LN/A 
0.0015 VN/A 
0.00097 CN/A 
0.0014 RN/A 
0.0092 VN/A 

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:   Td     Symmetry Number σ = 12


 Sym.   No   Approximate   Selected Freq.  Infrared   Raman   Comments 
 Species   type of mode   Value   Rating   Value  Phase  Value  Phase

a1 1 Sym str 2917  A  ia 2917.0 gas
e 2 Deg deform 1534  A 1533 ia gas 1533.6 Observed through Coriolis interaction with ν4
f2 3 Deg str 3019  A 3018.9 gas 3019.5
f2 4 Deg deform 1306  C 1306.2 gas

Source: Shimanouchi, 1972

Notes

iaInactive
A0~1 cm-1 uncertainty
C3~6 cm-1 uncertainty

References

Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Henry's Law 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.

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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]

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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]

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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]

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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]

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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]

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Notes

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