Selected ATcT [1, 2] enthalpy of formation based on version 1.122g of the Thermochemical Network [3]

This version of ATcT results was generated from an expansion of version 1.122e [4] to include results centered on the determination of the appearance energy of CH₃⁺ from CH₄. [5].

Species Name	Formula	Image	Δ_fH°(0 K)	Δ_fH°(298.15 K)	Uncertainty	Units	Relative Molecular Mass	ATcT ID
Ammonium hydroxide	NH4OH (aq, undissoc)			-366.716	± 0.062	kJ/mol	35.04584 ± 0.00047	1336-21-6*1000

Top contributors to the provenance of Δ_fH° of NH4OH (aq, undissoc)

The 20 contributors listed below account only for 85.2% of the provenance of Δ_fH° of NH4OH (aq, undissoc).
A total of 43 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
30.0	1435.1	NH3 (g) → NH3 (aq, undissoc)	Δ_rH°(298.15 K) = -8.448 ± 0.015 kcal/mol	Vanderzee 1972
10.8	1382.1	1/2 N2 (g) + 3/2 H2 (g) → NH3 (g)	Δ_rH°(298.15 K) = -10.885 ± 0.010 kcal/mol	Larson 1923, Vanderzee 1972
10.2	118.2	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
7.5	1435.2	NH3 (g) → NH3 (aq, undissoc)	Δ_rH°(298.15 K) = -8.456 ± 0.030 kcal/mol	Stavaley 1971, Vanderzee 1972, as quoted by CODATA Key Vals
7.5	1435.7	NH3 (g) → NH3 (aq, undissoc)	Δ_rH°(298.15 K) = -8.456 ± 0.030 kcal/mol	Staveley 1971, Vanderzee 1972
5.5	1381.5	1/2 N2 (g) + 3/2 H2 (g) → NH3 (g)	Δ_rH°(298.15 K) = -10.875 ± 0.014 kcal/mol	Schulz 1966, Vanderzee 1972
2.7	1435.3	NH3 (g) → NH3 (aq, undissoc)	Δ_rH°(298.15 K) = -8.442 ± 0.050 kcal/mol	Thomsen 1873, Vanderzee 1972
2.3	1381.4	1/2 N2 (g) + 3/2 H2 (g) → NH3 (g)	Δ_rH°(298.15 K) = -10.910 ± 0.015 (×1.445) kcal/mol	Larson 1924, Vanderzee 1972
1.3	1443.1	NH3 (g) + HON(O)O (aq) → [NH4]+ (aq) + [ON(O)O]- (aq)	Δ_rH°(298.15 K) = -87.23 ± 0.25 (×1.164) kJ/mol	Becker 1934, Vanderzee 1972a, as quoted by CODATA Key Vals
1.2	1444.1	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
0.9	1888.1	2 H2 (g) + C (graphite) → CH4 (g)	Δ_rG°(1165 K) = 37.521 ± 0.068 kJ/mol	Smith 1946, note COf, 3rd Law
0.7	1887.4	CH4 (g) + 2 O2 (g) → CO2 (g) + 2 H2O (cr,l)	Δ_rH°(298.15 K) = -890.61 ± 0.21 kJ/mol	Dale 2002
0.7	1382.8	1/2 N2 (g) + 3/2 H2 (g) → NH3 (g)	Δ_rG°(635 K) = 20.084 ± 0.157 kJ/mol	Schulz 1966, 3rd Law
0.6	1435.4	NH3 (g) → NH3 (aq, undissoc)	Δ_rH°(298.15 K) = -8.475 ± 0.100 kcal/mol	Baud 1909, Vanderzee 1972
0.5	1437.6	(NH4)Cl (cr) → NH3 (g) + HCl (g)	Δ_rH°(298.15 K) = 42.20 ± 0.06 (×1.719) kcal/mol	Braune 1928, JANAF 3, 3rd Law
0.5	161.1	[OH]- (g) → O- (g) + H (g)	Δ_rH°(0 K) = 4.7796 ± 0.0010 (×1.756) eV	Martin 2001, est unc
0.5	1887.6	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
0.4	1701.1	HON(O)O (aq, 1000 H2O) + NH3 (g) → (NH4)NO3 (cr,l)	Δ_rH°(298.15 K) = -27.22 ± 0.02 (×6.169) kcal/mol	Becker 1934, Parker 1965
0.3	1437.7	(NH4)Cl (cr) → NH3 (g) + HCl (g)	Δ_rH°(298.15 K) = 42.43 ± 0.09 (×1.445) kcal/mol	Rodebush 1929, JANAF 3, 2nd Law
0.3	1440.3	(NH4)NO3 (cr,l) → N2 (g) + 1/2 O2 (g) + 2 H2O (cr,l)	Δ_rH°(293.65 K) = -49.44 ± 0.06 kcal/mol	Becker 1934

Top 10 species with enthalpies of formation correlated to the Δ_fH° of NH4OH (aq, undissoc)

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
90.4	Ammonia	NH3 (aq, undissoc)		-80.886	± 0.053	kJ/mol	17.03056 ± 0.00022	7664-41-7*1000
85.9	Ammonium	[NH4]+ (aq)		-133.075	± 0.056	kJ/mol	18.03795 ± 0.00029	14798-03-9*800
75.8	Ammonium chloride	(NH4)Cl (cr)	-311.556	-314.718	± 0.063	kJ/mol	53.49120 ± 0.00095	12125-02-9*510
49.0	Water	H2O (g)	-238.932	-241.836	± 0.027	kJ/mol	18.01528 ± 0.00033	7732-18-5*0
49.0	Water	H2O (cr, l, eq.press.)	-286.304	-285.832	± 0.027	kJ/mol	18.01528 ± 0.00033	7732-18-5*499
49.0	Water	H2O (l, eq.press.)		-285.832	± 0.027	kJ/mol	18.01528 ± 0.00033	7732-18-5*589
49.0	Oxonium	[H3O]+ (aq)		-285.830	± 0.027	kJ/mol	19.02267 ± 0.00037	13968-08-6*800
49.0	Water	H2O (l)		-285.830	± 0.027	kJ/mol	18.01528 ± 0.00033	7732-18-5*590
49.0	Water	H2O (cr,l)	-286.302	-285.830	± 0.027	kJ/mol	18.01528 ± 0.00033	7732-18-5*500
49.0	Water	H2O (g, para)	-238.932	-241.836	± 0.027	kJ/mol	18.01528 ± 0.00033	7732-18-5*2

Most Influential reactions involving NH4OH (aq, undissoc)

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	1436.1	NH3 (aq, undissoc) + H2O (cr,l) → NH4OH (aq, undissoc)	Δ_rH°(298.15 K) = 0.000 ± 0.000 kJ/mol	triv

References (for your convenience, also available in RIS and BibTex format)

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. 1.122g of the Thermochemical Network (2019); available at ATcT.anl.gov
4		J. P. Porterfield, D. H. Bross, B. Ruscic, J. H. Thorpe, T. L. Nguyen, J. H. Baraban, J. F. Stanton, J. W. Daily, and G. B. Ellison, Thermal Decomposition of Potential Ester Biofuels, Part I: Methyl Acetate and Methyl Butanoate. J. Chem. Phys. A 121, 4658-4677 (2017) [DOI: 10.1021/acs.jpca.7b02639] (Veronica Vaida Festschrift)
5		Y.-C. Chang, B. Xiong, D. H. Bross, B. Ruscic, and C. Y. Ng, A Vacuum Ultraviolet laser Pulsed Field Ionization-Photoion Study of Methane (CH4): Determination of the Appearance Energy of Methylium From Methane with Unprecedented Precision and the Resulting Impact on the Bond Dissociation Energies of CH4 and CH4+. Phys. Chem. Chem. Phys. 19, 9592-9605 (2017) [DOI: 10.1039/c6cp08200a] (part of 2017 PCCP Hot Articles collection)
6		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]

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.

Selected ATcT [1, 2] enthalpy of formation based on version 1.122g of the Thermochemical Network [3]

Top contributors to the provenance of ΔfH° of NH4OH (aq, undissoc)

Top 10 species with enthalpies of formation correlated to the ΔfH° of NH4OH (aq, undissoc)

Most Influential reactions involving NH4OH (aq, undissoc)

Top contributors to the provenance of Δ_fH° of NH4OH (aq, undissoc)

Top 10 species with enthalpies of formation correlated to the Δ_fH° of NH4OH (aq, undissoc)