Selected ATcT [1, 2] enthalpy of formation based on version 1.130 of the Thermochemical Network [3]

This version of ATcT results[4] was generated by additional expansion of version 1.128 [5,6] to include with the calculations provided in reference [4].

Water

Formula: H2O (cr,l)

CAS RN: 7732-18-5

ATcT ID: 7732-18-5*500

SMILES: O

InChI: InChI=1S/H2O/h1H2

InChIKey: XLYOFNOQVPJJNP-UHFFFAOYSA-N

Hills Formula: H2O1

2D Image:

Aliases: Water; Oxidane; HOH; Dihydrogen oxide; Dihydrogen monoxide; Hydrogen oxide; Oxygen dyhydride; H2O

Relative Molecular Mass: 18.01528 ± 0.00033

Δ_fH°(0 K)	Δ_fH°(298.15 K)	Uncertainty	Units
-286.272	-285.800	± 0.022	kJ/mol

Top contributors to the provenance of Δ_fH° of H2O (cr,l)

The 20 contributors listed below account only for 66.4% of the provenance of Δ_fH° of H2O (cr,l).
A total of 269 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
30.1	121.2	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
8.8	2277.7	CH4 (g) + 2 O2 (g) → CO2 (g) + 2 H2O (cr,l)	Δ_rH°(298.15 K) = -890.578 ± 0.078 kJ/mol	Schley 2010
8.3	2279.1	2 H2 (g) + C (graphite) → CH4 (g)	Δ_rG°(1165 K) = 37.521 ± 0.068 kJ/mol	Smith 1946, note COf, 3rd Law
2.1	111.11	H2O (g) → O (g) + 2 H (g)	Δ_rH°(0 K) = 917.80 ± 0.15 kJ/mol	Thorpe 2021
2.0	153.1	OH (g) → [OH]+ (g)	Δ_rH°(0 K) = 104989 ± 5 (×2.278) cm-1	Wiedmann 1992, note unc
1.7	163.6	H2O (g) → [OH]+ (g) + H (g)	Δ_rH°(0 K) = 18.1183 ± 0.0015 (×1.022) eV	Bodi 2014
1.4	148.1	OH (g) → O (g) + H (g)	Δ_rH°(0 K) = 35580 ± 15 cm-1	Sun 2020
1.4	1702.1	N2 (g) + 3 H2O (cr,l) + 2 H+ (aq) → 3/2 O2 (g) + 2 [NH4]+ (aq)	Δ_rH°(298.15 K) = 141.292 ± 0.119 kcal/mol	Vanderzee 1972c
1.2	165.1	[OH]- (g) → O- (g) + H (g)	Δ_rH°(0 K) = 4.7796 ± 0.0010 (×2.044) eV	Martin 2001, est unc
1.2	2277.4	CH4 (g) + 2 O2 (g) → CO2 (g) + 2 H2O (cr,l)	Δ_rH°(298.15 K) = -890.61 ± 0.21 kJ/mol	Dale 2002
1.0	163.7	H2O (g) → [OH]+ (g) + H (g)	Δ_rH°(0 K) = 18.1190 ± 0.002 eV	Bodi 2014
0.9	2172.11	CO (g) → C (g) + O (g)	Δ_rH°(0 K) = 1071.92 ± 0.10 (×1.215) kJ/mol	Thorpe 2021
0.8	163.5	H2O (g) → [OH]+ (g) + H (g)	Δ_rH°(0 K) = 18.1177 ± 0.0015 (×1.445) eV	Bodi 2014
0.8	171.1	[OH]+ (g) → O+ (g) + H (g)	Δ_rH°(0 K) = 40412.0 ± 2.2 cm-1	Moselhy 1975, note unc
0.7	2277.8	CH4 (g) + 2 O2 (g) → CO2 (g) + 2 H2O (cr,l)	Δ_rH°(298.15 K) = -890.482 ± 0.260 kJ/mol	Haloua 2015
0.7	2277.6	CH4 (g) + 2 O2 (g) → CO2 (g) + 2 H2O (cr,l)	Δ_rH°(298.15 K) = -890.44 ± 0.26 kJ/mol	GOMB Ref Calorimeter, Alexandrov 2002
0.7	2189.3	CO (g) + H2O (g) → CO2 (g) + H2 (g)	Δ_rG°(893 K) = -6.369 ± 0.283 kJ/mol	Meyer 1938, note COi, 3rd Law
0.6	2182.2	CO (g) → C+ (g) + O (g)	Δ_rH°(0 K) = 22.3713 ± 0.0015 eV	Ng 2007
0.5	1517.4	NNO (g) + CO (g) → CO2 (g) + N2 (g)	Δ_rH°(293.15 K) = -365.642 ± 0.243 kJ/mol	Fenning 1933, note N2Oa
0.5	221.4	HOOH (g) → 2 H (g) + 2 O (g)	Δ_rH°(0 K) = 1054.84 ± 0.56 kJ/mol	Harding 2008

Top 10 species with enthalpies of formation correlated to the Δ_fH° of H2O (cr,l)

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
100.0	Water	H2O (l)		-285.800	± 0.022	kJ/mol	18.01528 ± 0.00033	7732-18-5*590
100.0	Water	H2O (g, ortho)	-238.617	-241.805	± 0.022	kJ/mol	18.01528 ± 0.00033	7732-18-5*1
100.0	Water	H2O (g, para)	-238.902	-241.805	± 0.022	kJ/mol	18.01528 ± 0.00033	7732-18-5*2
100.0	Water	H2O (g)	-238.902	-241.805	± 0.022	kJ/mol	18.01528 ± 0.00033	7732-18-5*0
100.0	Water	H2O (cr, l, eq.press.)	-286.274	-285.801	± 0.022	kJ/mol	18.01528 ± 0.00033	7732-18-5*499
100.0	Water	H2O (l, eq.press.)		-285.801	± 0.022	kJ/mol	18.01528 ± 0.00033	7732-18-5*589
100.0	Oxonium	[H3O]+ (aq)		-285.800	± 0.022	kJ/mol	19.02267 ± 0.00037	13968-08-6*800
99.9	Water	H2O (cr)	-286.272	-292.712	± 0.022	kJ/mol	18.01528 ± 0.00033	7732-18-5*510
99.9	Water	H2O (cr, eq.press.)	-286.274	-292.714	± 0.022	kJ/mol	18.01528 ± 0.00033	7732-18-5*509
99.8	Hydroxyl	OH (g)	37.279	37.518	± 0.022	kJ/mol	17.00734 ± 0.00031	3352-57-6*0

Most Influential reactions involving H2O (cr,l)

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
1.000	1755.1	NH3 (aq, 1 H2O) + H2O (cr,l) → NH4OH (cr,l)	Δ_rH°(298.15 K) = 0 ± 0 cm-1	triv
1.000	2054.1	(HON(O)O)(H2O) (cr,l) → HON(O)O (aq, 1 H2O) + H2O (cr,l)	Δ_rH°(298.15 K) = 0 ± 0 kJ/mol	triv
1.000	1698.1	NH3 (aq, undissoc) + H2O (cr,l) → NH4OH (aq, undissoc)	Δ_rH°(298.15 K) = 0.000 ± 0.000 kJ/mol	triv
1.000	212.1	H+ (aq) + H2O (cr,l) → [H3O]+ (aq)	Δ_rH°(298.15 K) = 0.000 ± 0.000 kJ/mol	triv
1.000	8913.1	(OS(O)(OH)2)(H2O)2 (cr,l) → OS(O)(OH)2 (cr,l) + 2 H2O (cr,l)	Δ_rH°(298.15 K) = 41.452 ± 0.004 kJ/mol	CODATA Key Vals, NBS TN270
1.000	8912.1	(OS(O)(OH)2)(H2O) (cr,l) → OS(O)(OH)2 (cr,l) + H2O (cr,l)	Δ_rH°(298.15 K) = 27.803 ± 0.004 kJ/mol	CODATA Key Vals, NBS TN270
1.000	5844.1	CH2CHCl (s, poly) + 5/2 O2 (g) → 2 CO2 (g) + H2O (cr,l) + HCl (aq, 600 H2O)	Δ_rH°(298.15 K) = -273.72 ± 0.3 kcal/mol	Sinke 1958, Manion 2002, note unc3
1.000	6478.1	2 ICH2CH2OH (l) + 11/2 O2 (g) → 4 CO2 (g) + 5 H2O (cr,l) + I2 (cr,l)	Δ_rH°(298.15 K) = -2588.56 ± 4.8 kJ/mol	Bernardes 2007
1.000	8915.1	(OS(O)(OH)2)(H2O)4 (cr,l) → OS(O)(OH)2 (cr,l) + 4 H2O (cr,l)	Δ_rH°(298.15 K) = 53.891 ± 0.004 kJ/mol	CODATA Key Vals, NBS TN270
1.000	7094.1	(CH3)2CHCH2C(CH3)3 (cr,l) + 25/2 O2 (g) → 8 CO2 (g) + 9 H2O (cr,l)	Δ_rH°(298.15 K) = -1305.30 ± 0.35 kcal/mol	Prosen 1945b, as quoted by Pedley 1986
1.000	8914.1	(OS(O)(OH)2)(H2O)3 (cr,l) → OS(O)(OH)2 (cr,l) + 3 H2O (cr,l)	Δ_rH°(298.15 K) = 48.924 ± 0.004 kJ/mol	CODATA Key Vals, NBS TN270
1.000	1763.1	NH3 (aq, 100 H2O) + H2O (cr,l) → NH4OH (aq, 100 H2O)	Δ_rH°(298.15 K) = 0.000 ± 0.006 kJ/mol	NBS Tables 1989
1.000	1760.1	NH3 (aq, 10 H2O) + H2O (cr,l) → NH4OH (aq, 10 H2O)	Δ_rH°(298.15 K) = -0.035 ± 0.006 kJ/mol	NBS Tables 1989
1.000	1767.1	NH3 (aq, 10000 H2O) + H2O (cr,l) → NH4OH (aq, 10000 H2O)	Δ_rH°(298.15 K) = 0.000 ± 0.006 kJ/mol	NBS Tables 1989
1.000	1768.1	NH3 (aq, 50000 H2O) + H2O (cr,l) → NH4OH (aq, 50000 H2O)	Δ_rH°(298.15 K) = 0.000 ± 0.006 kJ/mol	NBS Tables 1989
1.000	1764.1	NH3 (aq, 500 H2O) + H2O (cr,l) → NH4OH (aq, 500 H2O)	Δ_rH°(298.15 K) = 0.000 ± 0.006 kJ/mol	NBS Tables 1989
1.000	1765.1	NH3 (aq, 1000 H2O) + H2O (cr,l) → NH4OH (aq, 1000 H2O)	Δ_rH°(298.15 K) = 0.000 ± 0.006 kJ/mol	NBS Tables 1989
1.000	1766.1	NH3 (aq, 5000 H2O) + H2O (cr,l) → NH4OH (aq, 5000 H2O)	Δ_rH°(298.15 K) = 0.000 ± 0.006 kJ/mol	NBS Tables 1989
1.000	1769.1	NH3 (aq, 100000 H2O) + H2O (cr,l) → NH4OH (aq, 100000 H2O)	Δ_rH°(298.15 K) = 0.000 ± 0.006 kJ/mol	NBS Tables 1989
1.000	1762.1	NH3 (aq, 50 H2O) + H2O (cr,l) → NH4OH (aq, 50 H2O)	Δ_rH°(298.15 K) = -0.001 ± 0.006 kJ/mol	NBS Tables 1989

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. 1.130 of the Thermochemical Network. Argonne National Laboratory, Lemont, Illinois 2023; available at ATcT.anl.gov [DOI: 10.17038/CSE/1997229]
4		N. Genossar, P. B. Changala, B. Gans, J.-C. Loison, S. Hartweg, M.-A. Martin-Drumel, G. A. Garcia, J. F. Stanton, B. Ruscic, and J. H. Baraban Ring-Opening Dynamics of the Cyclopropyl Radical and Cation: the Transition State Nature of the Cyclopropyl Cation J. Am. Chem. Soc. 144, 18518-18525 (2022) [DOI: 10.1021/jacs.2c07740]
5		B. Ruscic and D. H. Bross Active Thermochemical Tables: The Thermophysical and Thermochemical Properties of Methyl, CH3, and Methylene, CH2, Corrected for Nonrigid Rotor and Anharmonic Oscillator Effects. Mol. Phys. e1969046 (2021) [DOI: 10.1080/00268976.2021.1969046]
6		J. H. Thorpe, J. L. Kilburn, D. Feller, P. B. Changala, D. H. Bross, B. Ruscic, and J. F. Stanton, Elaborated Thermochemical Treatment of HF, CO, N2, and H2O: Insight into HEAT and Its Extensions J. Chem. Phys. 155, 184109 (2021) [DOI: 10.1063/5.0069322]
7		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]
8		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 [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.