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].

Hydrogen chloride

Formula: HCl (aq)

CAS RN: 7647-01-0

ATcT ID: 7647-01-0*800

SMILES: Cl

InChI: InChI=1S/ClH/h1H

InChIKey: VEXZGXHMUGYJMC-UHFFFAOYSA-N

Hills Formula: Cl1H1

2D Image:

Aliases: HCl; Hydrogen chloride; Hydrogen monochloride; Hydrochloric acid; Chlorhydric acid; Chlorohydric acid; Chlorohydrogen; Chloric acid; Chlorine hydride; Chlorine monohydride

Relative Molecular Mass: 36.46064 ± 0.00090

Δ_fH°(0 K)	Δ_fH°(298.15 K)	Uncertainty	Units
	-166.990	± 0.023	kJ/mol

Top contributors to the provenance of Δ_fH° of HCl (aq)

The 7 contributors listed below account for 92.3% of the provenance of Δ_fH° of HCl (aq).

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
24.7	801.1	HCl (g) → HCl (aq)	Δ_rH°(298.15 K) = -17.884 ± 0.010 kcal/mol	Gunn 1963, Gunn 1964, as quoted by CODATA Key Vals, Vanderzee 1963, NBS Tables 1989
17.3	801.4	HCl (g) → HCl (aq)	Δ_rG°(298.15 K) = -36.009 ± 0.050 kJ/mol	Aston 1955, as quoted by CODATA Key Vals
17.3	801.5	HCl (g) → HCl (aq)	Δ_rG°(298.15 K) = -36.015 ± 0.050 kJ/mol	Bates 1919, as quoted by CODATA Key Vals
16.9	803.1	HCl (g) → HCl (aq, 2439 H2O)	Δ_rH°(298.15 K) = -17.810 ± 0.012 kcal/mol	Vanderzee 1963
6.7	801.3	HCl (g) → HCl (aq)	Δ_rG°(298.15 K) = -35.960 ± 0.080 kJ/mol	Haase 1963, as quoted by CODATA Key Vals
6.7	800.1	1/2 H2 (g) + 1/2 Cl2 (g) → HCl (aq)	Δ_rG°(298.15 K) = -31.320 ± 0.020 (×1.022) kcal/mol	Cerquetti 1968
2.5	788.1	HCl (g) → H+ (g) + Cl- (g)	Δ_rH°(0 K) = 116289.0 ± 0.6 cm-1	Martin 1998, note HCl

Top 10 species with enthalpies of formation correlated to the Δ_fH° of HCl (aq)

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°(298.15 K)	Uncertainty	Units	Relative Molecular Mass	ATcT ID
100.0	Chloride	Cl- (aq)	-166.990	± 0.023	kJ/mol	35.45325 ± 0.00090	16887-00-6*800
98.7	Hydrogen chloride	HCl (aq, 100 H2O)	-165.756	± 0.023	kJ/mol	36.46064 ± 0.00090	7647-01-0*828
98.0	Hydrogen chloride	HCl (aq, 2439 H2O)	-166.712	± 0.023	kJ/mol	36.46064 ± 0.00090	7647-01-0*951
97.1	Hydrogen chloride	HCl (aq, 900 H2O)	-166.542	± 0.023	kJ/mol	36.46064 ± 0.00090	7647-01-0*838
97.1	Hydrogen chloride	HCl (aq, 20 H2O)	-163.676	± 0.023	kJ/mol	36.46064 ± 0.00090	7647-01-0*818
97.1	Hydrogen chloride	HCl (aq, 800 H2O)	-166.517	± 0.023	kJ/mol	36.46064 ± 0.00090	7647-01-0*837
97.1	Hydrogen chloride	HCl (aq, 30 H2O)	-164.501	± 0.023	kJ/mol	36.46064 ± 0.00090	7647-01-0*820
97.1	Hydrogen chloride	HCl (aq, 75 H2O)	-165.555	± 0.023	kJ/mol	36.46064 ± 0.00090	7647-01-0*825
97.1	Hydrogen chloride	HCl (aq, 1500 H2O)	-166.635	± 0.023	kJ/mol	36.46064 ± 0.00090	7647-01-0*840
97.1	Hydrogen chloride	HCl (aq, 20000 H2O)	-166.886	± 0.023	kJ/mol	36.46064 ± 0.00090	7647-01-0*852

Most Influential reactions involving HCl (aq)

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	799.1	HCl (aq) → H+ (aq) + Cl- (aq)	Δ_rH°(298.15 K) = 0.000 ± 0.000 kcal/mol	triv
0.808	842.1	HCl (aq, 100 H2O) → HCl (aq)	Δ_rH°(298.15 K) = -1.234 ± 0.004 kJ/mol	NBS Tables 1989, NBS TN270, Parker 1965
0.545	843.2	HCl (aq, 2439 H2O) → HCl (aq)	Δ_rH°(298.15 K) = -0.278 ± 0.006 kJ/mol	NBS Tables 1989
0.265	801.1	HCl (g) → HCl (aq)	Δ_rH°(298.15 K) = -17.884 ± 0.010 kcal/mol	Gunn 1963, Gunn 1964, as quoted by CODATA Key Vals, Vanderzee 1963, NBS Tables 1989
0.185	801.5	HCl (g) → HCl (aq)	Δ_rG°(298.15 K) = -36.015 ± 0.050 kJ/mol	Bates 1919, as quoted by CODATA Key Vals
0.185	801.4	HCl (g) → HCl (aq)	Δ_rG°(298.15 K) = -36.009 ± 0.050 kJ/mol	Aston 1955, as quoted by CODATA Key Vals
0.072	801.3	HCl (g) → HCl (aq)	Δ_rG°(298.15 K) = -35.960 ± 0.080 kJ/mol	Haase 1963, as quoted by CODATA Key Vals
0.070	843.1	HCl (aq, 2439 H2O) → HCl (aq)	Δ_rH°(298.15 K) = -0.065 ± 0.004 kcal/mol	Vanderzee 1963, Sturtevant 1940, Sturtevant 1940b, Sturtevant 1942, est unc
0.067	800.1	1/2 H2 (g) + 1/2 Cl2 (g) → HCl (aq)	Δ_rG°(298.15 K) = -31.320 ± 0.020 (×1.022) kcal/mol	Cerquetti 1968
0.017	800.2	1/2 H2 (g) + 1/2 Cl2 (g) → HCl (aq)	Δ_rH°(298.15 K) = -39.891 ± 0.040 kcal/mol	Cerquetti 1968
0.005	801.2	HCl (g) → HCl (aq)	Δ_rH°(298.15 K) = -74.52 ± 0.30 kJ/mol	Roth 1937, as quoted by CODATA Key Vals
0.002	1136.1	2 HBr (aq) + Cl2 (g) → 2 HCl (aq) + Br2 (aq)	Δ_rH°(298.15 K) = -21.2 ± 1.2 (×1.325) kcal/mol	Wartenberg 1930, Wartenberg 1931, Parker 1965

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.