Selected ATcT [1, 2] enthalpy of formation based on version 1.172 of the Thermochemical Network [3]

This version of ATcT results[3] was generated by additional expansion of version 1.156 to include species relevant to a study of photodissociation of formamide[4].

Sulfuric acid

Formula: OS(O)(OH)2 (aq, 75 H2O)

CAS RN: 7664-93-9

ATcT ID: 7664-93-9*825

SMILES: OS(=O)(=O)O

InChI: InChI=1S/H2O4S/c1-5(2,3)4/h(H2,1,2,3,4)

InChIKey: QAOWNCQODCNURD-UHFFFAOYSA-N

Hills Formula: H2O4S1

2D Image:

Aliases: OS(O)(OH)2; Sulfuric acid; Hydrogen sulfate; Dipping acid; Oil of vitriol; Vitriol brown oil; Vitriol; Brimstone acid; Matting acid; Nordhausen acid; Contact acid; BOV; UN 1832; UN 2796; O2S(OH)2; (O2S)(OH)2; (SO2)(OH)2; S(O)(O)(OH)2; S(O)2(OH)2; H2SO4

Relative Molecular Mass: 98.0795 ± 0.0061

Δ_fH°(0 K)	Δ_fH°(298.15 K)	Uncertainty	Units
	-887.18	± 0.13	kJ/mol

Top contributors to the provenance of Δ_fH° of OS(O)(OH)2 (aq, 75 H2O)

The 8 contributors listed below account for 90.7% of the provenance of Δ_fH° of OS(O)(OH)2 (aq, 75 H2O).

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
30.5	9369.1	S (cr,l) + O2 (g) → OSO (g)	Δ_rH°(298.15 K) = -296.847 ± 0.200 kJ/mol	Eckman 1929, note SO2
22.5	9516.1	S (cr,l) + 3/2 O2 (g) + H2O (cr,l) → OS(O)(OH)2 (aq, 115 H2O)	Δ_rH°(298.15 K) = -143.85 ± 0.06 kcal/mol	Good 1960, CODATA Key Vals
16.5	9516.2	S (cr,l) + 3/2 O2 (g) + H2O (cr,l) → OS(O)(OH)2 (aq, 115 H2O)	Δ_rH°(298.15 K) = -143.92 ± 0.07 kcal/mol	Mansson 1963, CODATA Key Vals
6.7	9555.1	S (cr,l) + 3/2 O2 (g) + H2O (cr,l) → OS(O)(OH)2 (aq, 45 H2O)	Δ_rH°(298.15 K) = -143.67 ± 0.11 kcal/mol	McCullough 1957a
4.5	9515.1	S (cr,l) + 3/2 O2 (g) + H2O (cr,l) → OS(O)(OH)2 (aq, 70 H2O)	Δ_rH°(298.15 K) = -143.58 ± 0.09 (×1.477) kcal/mol	McCullough 1953, CODATA Key Vals
3.7	9354.2	2 S (cr,l) → S2 (g)	Δ_rG°(570 K) = 9.483 ± 0.138 (×1.915) kcal/mol	Drowart 1968, Detry 1967, 3rd Law
3.1	9516.3	S (cr,l) + 3/2 O2 (g) + H2O (cr,l) → OS(O)(OH)2 (aq, 115 H2O)	Δ_rH°(298.15 K) = -143.70 ± 0.07 (×2.278) kcal/mol	Waddington 1956, Mansson 1963, est unc
2.8	9354.4	2 S (cr,l) → S2 (g)	Δ_rG°(600 K) = 8.57 ± 0.29 (×1.044) kcal/mol	Braune 1951, West 1929, Gurvich TPIS, 3rd Law

Top 10 species with enthalpies of formation correlated to the Δ_fH° of OS(O)(OH)2 (aq, 75 H2O)

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
99.9	Sulfuric acid	OS(O)(OH)2 (aq, 100 H2O)	-887.53	± 0.13	kJ/mol	98.0795 ± 0.0061	7664-93-9*828
99.9	Sulfuric acid	OS(O)(OH)2 (aq, 50 H2O)	-886.66	± 0.13	kJ/mol	98.0795 ± 0.0061	7664-93-9*822
99.9	Sulfuric acid	OS(O)(OH)2 (aq, 40 H2O)	-886.35	± 0.13	kJ/mol	98.0795 ± 0.0061	7664-93-9*821
99.9	Sulfuric acid	OS(O)(OH)2 (aq, 700 H2O)	-891.25	± 0.13	kJ/mol	98.0795 ± 0.0061	7664-93-9*835
99.9	Sulfuric acid	OS(O)(OH)2 (aq, 800 H2O)	-891.62	± 0.13	kJ/mol	98.0795 ± 0.0061	7664-93-9*837
99.9	Sulfuric acid	OS(O)(OH)2 (aq, 15 H2O)	-883.51	± 0.13	kJ/mol	98.0795 ± 0.0061	7664-93-9*817
99.9	Sulfuric acid	OS(O)(OH)2 (aq, 300 H2O)	-889.26	± 0.13	kJ/mol	98.0795 ± 0.0061	7664-93-9*831
99.9	Sulfuric acid	OS(O)(OH)2 (aq, 30 H2O)	-885.87	± 0.13	kJ/mol	98.0795 ± 0.0061	7664-93-9*820
99.9	Sulfuric acid	OS(O)(OH)2 (aq, 1000 H2O)	-892.23	± 0.13	kJ/mol	98.0795 ± 0.0061	7664-93-9*839
99.9	Sulfuric acid	OS(O)(OH)2 (aq, 150 H2O)	-888.08	± 0.13	kJ/mol	98.0795 ± 0.0061	7664-93-9*829

Most Influential reactions involving OS(O)(OH)2 (aq, 75 H2O)

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
0.687	9528.1	OS(O)(OH)2 (aq, 75 H2O) → OS(O)(OH)2 (aq, 100 H2O)	Δ_rH°(298.15 K) = -0.344 ± 0.004 kJ/mol	CODATA Key Vals, NBS TN270
0.574	9558.1	OS(O)(OH)2 (aq, 60 H2O) → OS(O)(OH)2 (aq, 75 H2O)	Δ_rH°(298.15 K) = -0.276 ± 0.008 kJ/mol	CODATA Key Vals
0.574	9561.1	OS(O)(OH)2 (aq, 70 H2O) → OS(O)(OH)2 (aq, 75 H2O)	Δ_rH°(298.15 K) = -0.083 ± 0.008 kJ/mol	CODATA Key Vals
0.543	9562.1	OS(O)(OH)2 (aq, 75 H2O) → OS(O)(OH)2 (aq, 80 H2O)	Δ_rH°(298.15 K) = -0.077 ± 0.008 kJ/mol	CODATA Key Vals
0.543	9564.1	OS(O)(OH)2 (aq, 75 H2O) → OS(O)(OH)2 (aq, 90 H2O)	Δ_rH°(298.15 K) = -0.218 ± 0.008 kJ/mol	CODATA Key Vals

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. 1.172 of the Thermochemical Network (2024); available at ATcT.anl.gov
4		K. L. Caster, N. A. Seifert, B. Ruscic, A. W. Jasper, and K. Prozument, Dynamics of HCN, NHC, and HNCO Formation in the 193 nm Photodissociation of Formamide J. Phys. Chem. A (in press) (2024) [DOI: 10.1021/acs.jpca.4c02232]
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.