Selected ATcT [1, 2] enthalpy of formation based on version 1.176 of the Thermochemical Network [3]

This version of ATcT results[3] was generated by additional expansion of version 1.172 to include species related to Criegee intermediates that are involved in several ongoing studies[4].

Ethane

Formula: CH3CH3 (g)

CAS RN: 74-84-0

ATcT ID: 74-84-0*0

SMILES: CC

InChI: InChI=1S/C2H6/c1-2/h1-2H3

InChIKey: OTMSDBZUPAUEDD-UHFFFAOYSA-N

Hills Formula: C2H6

2D Image:

Aliases: CH3CH3; Ethane; Dimethyl; Bimethyl; Ethyl hydride; Methylmethane; C2H6 g; CH3CH3 g; CH3-CH3; UN 1035; UN 1961

Relative Molecular Mass: 30.0690 ± 0.0017

Δ_fH°(0 K)	Δ_fH°(298.15 K)	Uncertainty	Units
-68.40	-84.03	± 0.12	kJ/mol

3D Image of CH3CH3 (g)

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Top contributors to the provenance of Δ_fH° of CH3CH3 (g)

The 20 contributors listed below account only for 44.5% of the provenance of Δ_fH° of CH3CH3 (g).
A total of 976 contributors would be needed to account for 90% of the provenance.

Please note: The list is limited to 20 most important contributors or, if less, a number sufficient to account for 90% of the provenance. The Reference acts as a further link to the relevant references and notes for the measurement. The Measured Quantity is normaly given in the original units; in cases where we have reinterpreted the original measurement, the listed value may differ from that given by the authors. The quoted uncertainty is the a priori uncertainty used as input when constructing the initial Thermochemical Network, and corresponds either to the value proposed by the original authors or to our estimate; if an additional multiplier is given in parentheses immediately after the prior uncertainty, it corresponds to the factor by which the prior uncertainty needed to be multiplied during the ATcT analysis in order to make that particular measurement consistent with the prevailing knowledge contained in the Thermochemical Network.

Contribution (%)	TN ID	Reaction	Measured Quantity	Reference
5.9	2469.1	CH3CH3 (g) + 7/2 O2 (g) → 2 CO2 (g) + 3 H2O (cr,l)	Δ_rH°(298.15 K) = -1560.68 ± 0.25 (×1.384) kJ/mol	Pittam 1972
5.8	2375.1	2 H2 (g) + C (graphite) → CH4 (g)	Δ_rG°(1165 K) = 37.521 ± 0.068 kJ/mol	Smith 1946, note COf, 3rd Law
5.3	2530.1	CH2CH2 (g) + H2 (g) → CH3CH3 (g)	Δ_rH°(355.15 K) = -32.831 ± 0.05 kcal/mol	Kistiakowsky 1935
3.3	125.2	1/2 O2 (g) + H2 (g) → H2O (cr,l)	Δ_rH°(298.15 K) = -285.8261 ± 0.040 kJ/mol	Rossini 1939, Rossini 1931, Rossini 1931b, note H2Oa, Rossini 1930
3.1	9233.2	C6H4(C2H2(CC(C4H4))) (g) + 18 CH4 (g) → 9 CH3CH3 (g) + 7 CH2CH2 (g)	Δ_rH°(0 K) = 776.95 ± 6 kJ/mol	Dorofeeva 2022, est unc
2.5	2530.2	CH2CH2 (g) + H2 (g) → CH3CH3 (g)	Δ_rG°(723.15 K) = -10.867 ± 0.072 kcal/mol	Kistiakowsky 1951
2.5	2469.2	CH3CH3 (g) + 7/2 O2 (g) → 2 CO2 (g) + 3 H2O (cr,l)	Δ_rH°(298.15 K) = -372.805 ± 0.110 (×1.139) kcal/mol	Prosen 1945, Rossini 1934
2.0	2529.1	CH2CH2 (g) + 3 O2 (g) → 2 CO2 (g) + 2 H2O (cr,l)	Δ_rH°(298.15 K) = -1411.18 ± 0.30 kJ/mol	Rossini 1937
1.7	3255.12	CH3CH2CH3 (g) + CH4 (g) → 2 CH3CH3 (g)	Δ_rH°(0 K) = 2.96 ± 0.20 kcal/mol	Karton 2011, Karton 2009b
1.6	8261.6	CH(CH(CHCH)) (g) + 8 CH4 (g) → 6 CH3CH3 (g)	Δ_rH°(0 K) = -428.9 ± 3.0 (×1.067) kJ/mol	Klopper 2010a, Klopper 2009, est unc
1.4	9196.2	C6H4(C4H4) (g) + 12 CH4 (g) → 6 CH3CH3 (g) + 5 CH2CH2 (g)	Δ_rH°(0 K) = 516.00 ± 6 kJ/mol	Dorofeeva 2022, est unc
1.3	3253.1	CH3CH2CH3 (g) + 5 O2 (g) → 3 CO2 (g) + 4 H2O (cr,l)	Δ_rH°(298.15 K) = -2219.15 ± 0.46 (×1.114) kJ/mol	Pittam 1972
1.2	2530.3	CH2CH2 (g) + H2 (g) → CH3CH3 (g)	Δ_rG°(653.15 K) = -13.114 ± 0.104 kcal/mol	Kistiakowsky 1951
1.2	2228.7	C (graphite) + O2 (g) → CO2 (g)	Δ_rH°(298.15 K) = -393.464 ± 0.024 kJ/mol	Hawtin 1966, note CO2e
1.1	2268.11	CO (g) → C (g) + O (g)	Δ_rH°(0 K) = 1071.92 ± 0.10 kJ/mol	Thorpe 2021
0.8	2611.11	HCCH (g) + 2 H2 (g) → CH3CH3 (g)	Δ_rH°(0 K) = -71.01 ± 0.20 kcal/mol	Karton 2007
0.8	3463.11	CH3CCH (g) + CH4 (g) → HCCH (g) + CH3CH3 (g)	Δ_rH°(0 K) = 33.87 ± 0.8 kJ/mol	Ferguson 2013, est unc
0.7	3255.10	CH3CH2CH3 (g) + CH4 (g) → 2 CH3CH3 (g)	Δ_rH°(0 K) = 3.00 ± 0.30 kcal/mol	Karton 2011
0.6	2286.9	C (graphite) + CO2 (g) → 2 CO (g)	Δ_rG°(1165 K) = -33.545 ± 0.058 kJ/mol	Smith 1946, note COf, 3rd Law
0.6	2611.1	HCCH (g) + 2 H2 (g) → CH3CH3 (g)	Δ_rH°(355.15 K) = -75.078 ± 0.150 (×1.509) kcal/mol	Conn 1939, note C2H2

Top 10 species with enthalpies of formation correlated to the Δ_fH° of CH3CH3 (g)

Please note: The correlation coefficients are obtained by renormalizing the off-diagonal elements of the covariance matrix by the corresponding variances.
The correlation coefficient is a number from -1 to 1, with 1 representing perfectly correlated species, -1 representing perfectly anti-correlated species, and 0 representing perfectly uncorrelated species.

Correlation Coefficent (%)	Species Name	Formula	Δ_fH°(0 K)	Δ_fH°(298.15 K)	Uncertainty	Units	Relative Molecular Mass	ATcT ID
67.2	Propane	CH3CH2CH3 (g)	-82.73	-105.01	± 0.15	kJ/mol	44.0956 ± 0.0025	74-98-6*0
61.3	Ethylene	CH2CH2 (g)	60.89	52.38	± 0.11	kJ/mol	28.0532 ± 0.0016	74-85-1*0
61.2	Ethylene cation	[CH2CH2]+ (g)	1075.21	1067.99	± 0.11	kJ/mol	28.0526 ± 0.0016	34470-02-5*0
47.1	n-Butane	CH3CH2CH2CH3 (g)	-98.25	-125.56	± 0.18	kJ/mol	58.1222 ± 0.0033	106-97-8*0
46.1	Propene	CH3CHCH2 (g)	34.89	20.06	± 0.18	kJ/mol	42.0797 ± 0.0024	115-07-1*0
46.0	Propylene cation	[CH3CHCH2]+ (g)	975.18	961.65	± 0.18	kJ/mol	42.0792 ± 0.0024	34504-10-4*0
42.4	iso-Propylium	[CH3CHCH3]+ (g)	822.97	805.89	± 0.23	kJ/mol	43.0871 ± 0.0024	19252-53-0*0
39.0	Ethyl	CH3CH2 (g)	131.50	120.75	± 0.20	kJ/mol	29.0611 ± 0.0016	2025-56-1*0
38.3	Methane	CH4 (g)	-66.547	-74.516	± 0.043	kJ/mol	16.04246 ± 0.00085	74-82-8*0
37.7	Allyl anion	[CH2CHCH2]- (g)	134.00	122.99	± 0.21	kJ/mol	41.0723 ± 0.0024	1724-46-5*0

Most Influential reactions involving CH3CH3 (g)

Please note: The list, which is based on a hat (projection) matrix analysis, is limited to no more than 20 largest influences.

Influence Coefficient	TN ID	Reaction	Measured Quantity	Reference
0.813	2464.8	[CH3CH3]- (g) → CH3CH3 (g)	Δ_rH°(0 K) = -1.143 ± 0.050 eV	Ruscic W1RO
0.731	2462.6	CH3CH3 (g) → [CH3CH3]+ (g)	Δ_rH°(0 K) = 11.521 ± 0.007 eV	Nicholson 1965
0.252	8635.7	SiH3SiH3 (g) + 2 CH4 (g) → CH3CH3 (g) + 2 SiH4 (g)	Δ_rH°(0 K) = 13.99 ± 0.2 kcal/mol	Karton 2011, Karton 2007b
0.236	5317.6	CH2C(O)OH (g, syn) + CH3CH3 (g) → CH3C(O)OH (g, syn) + CH3CH2 (g)	Δ_rH°(0 K) = 7.41 ± 2.00 kJ/mol	Klippenstein 2017
0.236	7539.6	CH2N(O)O (g) + CH3CH3 (g) → CH3N(O)O (g) + CH3CH2 (g)	Δ_rH°(0 K) = -1.76 ± 2.0 kJ/mol	Klippenstein 2017
0.231	4464.4	O(CHCH) (g, singlet) + CH3CH3 (g) → O(CH2CH2) (g) + CH2CH2 (g)	Δ_rH°(0 K) = -43.57 ± 0.30 kcal/mol	Karton 2011
0.230	2485.3	[C2H7]+ (g) + CO (g) → [HCO]+ (g) + CH3CH3 (g)	Δ_rG°(298.15 K) = 1.43 ± 0.3 kcal/mol	Mackay 1981, 3rd Law, note unc5
0.227	5575.5	CH3CH2N (g) + CH3CH3 (g) → CH3N (g) + CH3CH2CH3 (g)	Δ_rH°(0 K) = 0.56 ± 0.85 kcal/mol	Ruscic W1RO
0.216	5302.9	HC(O)OCH2 (g, syn) + CH3CH3 (g) → HC(O)OCH3 (g, syn) + CH3CH2 (g)	Δ_rH°(0 K) = 4.04 ± 2.00 kJ/mol	Klippenstein 2017
0.214	6605.6	3 CH2FCH2F (g) → CF3CF3 (g) + 2 CH3CH3 (g)	Δ_rH°(0 K) = -166.144 ± 5.0 kJ/mol	Nagy 2014, est unc
0.209	7619.5	(CH2C(O)OH)2 (g) + 2 CH3 (g) → 2 CH2C(O)OH (g, syn) + CH3CH3 (g)	Δ_rH°(0 K) = -4.89 ± 0.9 kcal/mol	Ruscic W1RO
0.205	2530.1	CH2CH2 (g) + H2 (g) → CH3CH3 (g)	Δ_rH°(355.15 K) = -32.831 ± 0.05 kcal/mol	Kistiakowsky 1935
0.202	5575.4	CH3CH2N (g) + CH3CH3 (g) → CH3N (g) + CH3CH2CH3 (g)	Δ_rH°(0 K) = 0.64 ± 0.90 kcal/mol	Ruscic CBS-n
0.202	5575.2	CH3CH2N (g) + CH3CH3 (g) → CH3N (g) + CH3CH2CH3 (g)	Δ_rH°(0 K) = 0.80 ± 0.90 kcal/mol	Ruscic G4
0.202	5575.1	CH3CH2N (g) + CH3CH3 (g) → CH3N (g) + CH3CH2CH3 (g)	Δ_rH°(0 K) = 0.53 ± 0.90 kcal/mol	Ruscic G3X
0.198	3367.6	CH3CH2CH (g, triplet gauche) + CH3CH3 (g) → CH3CH (g, triplet) + CH3CH2CH3 (g)	Δ_rH°(0 K) = -2.89 ± 2.0 kJ/mol	Klippenstein 2017
0.198	3257.2	[CH3CH2CH3]+ (g) + CH3CH3 (g) → CH3CH2CH3 (g) + [CH3CH3]+ (g)	Δ_rH°(0 K) = 0.580 ± 0.039 eV	Ruscic G3X
0.189	6599.11	CH3CH2F (g) + CH4 (g) → CH3F (g) + CH3CH3 (g)	Δ_rH°(0 K) = 6.78 ± 0.20 kcal/mol	Karton 2011
0.178	6609.6	3 CH3CHF2 (g) → CF3CF3 (g) + 2 CH3CH3 (g)	Δ_rH°(0 K) = -2.037 ± 3.3 kJ/mol	Nagy 2014, est unc
0.170	7632.2	CH3CHBr2 (g) + CH3CH3 (g) → 2 CH3CH2Br (g)	Δ_rH°(0 K) = -1.68 ± 1.0 kcal/mol	Ruscic G4

References

1		B. Ruscic, R. E. Pinzon, M. L. Morton, G. von Laszewski, S. Bittner, S. G. Nijsure, K. A. Amin, M. Minkoff, and A. F. Wagner, Introduction to Active Thermochemical Tables: Several "Key" Enthalpies of Formation Revisited. J. Phys. Chem. A 108, 9979-9997 (2004) [DOI: 10.1021/jp047912y]
2		B. Ruscic, R. E. Pinzon, G. von Laszewski, D. Kodeboyina, A. Burcat, D. Leahy, D. Montoya, and A. F. Wagner, Active Thermochemical Tables: Thermochemistry for the 21^st Century. J. Phys. Conf. Ser. 16, 561-570 (2005) [DOI: 10.1088/1742-6596/16/1/078]
3		B. Ruscic and D. H. Bross, Active Thermochemical Tables (ATcT) values based on ver. 1.176 of the Thermochemical Network (2024); available at ATcT.anl.gov
4		T. L. Nguyen et al, ongoing studies (2024)
5		B. Ruscic, Uncertainty Quantification in Thermochemistry, Benchmarking Electronic Structure Computations, and Active Thermochemical Tables. Int. J. Quantum Chem. 114, 1097-1101 (2014) [DOI: 10.1002/qua.24605]
6		B. Ruscic and D. H. Bross, Thermochemistry Computer Aided Chem. Eng. 45, 3-114 (2019) [DOI: 10.1016/B978-0-444-64087-1.00001-2]

Formula

The aggregate state is given in parentheses following the formula, such as: g - gas-phase, cr - crystal, l - liquid, etc.

Uncertainties

The listed uncertainties correspond to estimated 95% confidence limits, as customary in thermochemistry (see, for example, Ruscic [5] and Ruscic and Bross[6]).
Note that an uncertainty of ± 0.000 kJ/mol indicates that the estimated uncertainty is < ± 0.000₅ kJ/mol.

Website Functionality Credits

The reorganization of the website was developed and implemented by David H. Bross (ANL).
The find function is based on the complete Species Dictionary entries for the appropriate version of the ATcT TN.
The molecule images are rendered by Indigo-depict.
The XYZ renderings are based on Jmol: an open-source Java viewer for chemical structures in 3D. http://www.jmol.org/.

Acknowledgement

This work was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences and Biosciences under Contract No. DE-AC02-06CH11357.