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].

Nitrous acid

Formula: HONO (g)
CAS RN: 7782-77-6
ATcT ID: 7782-77-6*0
SMILES: N(=O)O
InChI: InChI=1S/HNO2/c2-1-3/h(H,2,3)
InChIKey: IOVCWXUNBOPUCH-UHFFFAOYSA-N
Hills Formula: H1N1O2

2D Image:

N(=O)O
Aliases: HONO; Nitrous acid; Nytrosyl hydroxide; ONOH; HO-N=O; O=N-OH
Relative Molecular Mass: 47.01348 ± 0.00061

   ΔfH°(0 K)   ΔfH°(298.15 K)UncertaintyUnits
-72.987-78.644± 0.077kJ/mol

3D Image of HONO (g)

spin ON           spin OFF
          

Top contributors to the provenance of ΔfH° of HONO (g)

The 20 contributors listed below account only for 81.2% of the provenance of ΔfH° of HONO (g).
A total of 50 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
20.71999.8 NO (g) ONO (g) H2O (g) → 2 HONO (g) ΔrG°(298.15 K) = -1.44 ± 0.10 kJ/molVosper 1976, 3rd Law
15.31483.2 NO (g) → N (g) O (g) ΔrH°(0 K) = 52400 ± 10 cm-1Dingle 1975
15.31483.1 NO (g) → N (g) O (g) ΔrH°(0 K) = 52400 ± 10 cm-1Callear 1970
11.21483.4 NO (g) → N (g) O (g) ΔrH°(0 K) = 52408 ± 10 (×1.164) cm-1Kley 1973, Miescher 1974, est unc
3.31999.2 NO (g) ONO (g) H2O (g) → 2 HONO (g) ΔrG°(298.15 K) = -1.25 ± 0.25 kJ/molWayne 1951, 3rd Law
2.61483.3 NO (g) → N (g) O (g) ΔrH°(0 K) = 52420 ± 12 (×2) cm-1Miescher 1974, Huber 1979
2.02000.3 ONN(O)O (g) H2O (g) → 2 HONO (g) ΔrG°(298.15 K) = -3.26 ± 0.15 (×2.044) kJ/molVosper 1976, 3rd Law
1.61436.3 N2 (g) → N+ (g) N (g) ΔrH°(0 K) = 24.2880 ± 0.0009 eVTang 2005
1.31436.1 N2 (g) → N+ (g) N (g) ΔrH°(0 K) = 24.2888 ± 0.0010 eVTang 2005
1.31436.2 N2 (g) → N+ (g) N (g) ΔrH°(0 K) = 24.2883 ± 0.0010 eVTang 2005
1.01725.3 (NH4)NO3 (cr,l) → N2 (g) + 1/2 O2 (g) + 2 H2O (cr,l) ΔrH°(293.65 K) = -49.44 ± 0.06 kcal/molBecker 1934
0.7125.2 1/2 O2 (g) H2 (g) → H2O (cr,l) ΔrH°(298.15 K) = -285.8261 ± 0.040 kJ/molRossini 1939, Rossini 1931, Rossini 1931b, note H2Oa, Rossini 1930
0.61486.4 NO (g) → N (g) O (g) ΔrH°(0 K) = 626.47 ± 0.56 kJ/molHarding 2008
0.62002.1 HONO (g, trans) → OH (g) NO (g) ΔrH°(0 K) = 16772 ± 14 (×1.509) cm-1Reiche 2000, Reiche 2002, Dieke 1962
0.51485.10 NO (g) → N (g) O (g) ΔrH°(0 K) = 149.82 ± 0.15 kcal/molKarton 2007a, Karton 2008
0.51413.11 N2 (g) → 2 N (g) ΔrH°(0 K) = 941.14 ± 0.15 kJ/molThorpe 2021
0.51483.6 NO (g) → N (g) O (g) ΔrH°(0 K) = 6.503 ± 0.004 (×1.682) eVBrewer 1956, Frisch 1965
0.41484.10 NO (g) → N (g) O (g) ΔrH°(0 K) = 149.78 ± 0.16 kcal/molFeller 2014
0.41952.4 HNO (g) → H (g) N (g) O (g) ΔrH°(0 K) = 823.10 ± 0.56 kJ/molHarding 2008
0.41999.4 NO (g) ONO (g) H2O (g) → 2 HONO (g) ΔrG°(323 K) = 2.57 ± 0.22 (×3.084) kJ/molAshmore 1961, 3rd Law

Top 10 species with enthalpies of formation correlated to the ΔfH° of HONO (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 Image    ΔfH°(0 K)    ΔfH°(298.15 K) Uncertainty Units Relative
Molecular
Mass
ATcT ID
100.0 Nitrous acidHONO (g, trans)N(=O)O-72.987-79.131± 0.077kJ/mol47.01348 ±
0.00061
7782-77-6*1
82.4 Nitrogen dioxideONO (g)O=[N]=O36.86634.059± 0.064kJ/mol46.00554 ±
0.00060
10102-44-0*0
82.4 Nitric oxideNO (g)[N]=O90.62791.131± 0.064kJ/mol30.00614 ±
0.00031
10102-43-9*0
82.3 Nitrosyl ion[NO]+ (g)N#[O+]984.494984.489± 0.064kJ/mol30.00559 ±
0.00031
14452-93-8*0
80.1 Dinitrogen tetraoxideO2NNO2 (g)O=N(=O)N(=O)=O20.1710.88± 0.14kJ/mol92.0111 ±
0.0012
10544-72-6*0
79.5 Nitrosyl chlorideClNO (g)ClN=O54.46152.559± 0.067kJ/mol65.45884 ±
0.00095
2696-92-6*0
77.6 DioxohydrazineONNO (g, cis)O=NN=O172.91171.14± 0.14kJ/mol60.01228 ±
0.00062
16824-89-8*2
77.6 DioxohydrazineONNO (g)O=NN=O172.91171.14± 0.14kJ/mol60.01228 ±
0.00062
16824-89-8*0
75.3 Nitrogen sesquioxideONN(O)O (g)O=N-[N](=O)[O]90.7486.17± 0.15kJ/mol76.01168 ±
0.00091
10544-73-7*0
67.6 Nitric oxideNO (aq, undissoc)[N]=O79.218± 0.078kJ/mol30.00614 ±
0.00031
10102-43-9*1000

Most Influential reactions involving HONO (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
1.0001992.1 HONO (g, trans) → HONO (g) ΔrH°(0 K) = 0 ± 0 cm-1Sironneau 2010, Ruscic G3B3
0.7101999.8 NO (g) ONO (g) H2O (g) → 2 HONO (g) ΔrG°(298.15 K) = -1.44 ± 0.10 kJ/molVosper 1976, 3rd Law
0.1131999.2 NO (g) ONO (g) H2O (g) → 2 HONO (g) ΔrG°(298.15 K) = -1.25 ± 0.25 kJ/molWayne 1951, 3rd Law
0.1102000.3 ONN(O)O (g) H2O (g) → 2 HONO (g) ΔrG°(298.15 K) = -3.26 ± 0.15 (×2.044) kJ/molVosper 1976, 3rd Law
0.0151999.4 NO (g) ONO (g) H2O (g) → 2 HONO (g) ΔrG°(323 K) = 2.57 ± 0.22 (×3.084) kJ/molAshmore 1961, 3rd Law
0.0141999.1 NO (g) ONO (g) H2O (g) → 2 HONO (g) ΔrG°(298.15 K) = -1.33 ± 0.69 kJ/molWayne 1951, 3rd Law
0.0141999.6 NO (g) ONO (g) H2O (g) → 2 HONO (g) ΔrG°(296 K) = -0.97 ± 0.39 (×1.795) kJ/molWaldorf 1963, 3rd Law
0.0121999.3 NO (g) ONO (g) H2O (g) → 2 HONO (g) ΔrG°(298.15 K) = -1.17 ± 0.75 kJ/molKaravaev 1962, Wayne 1951, 3rd Law
0.0031999.9 NO (g) ONO (g) H2O (g) → 2 HONO (g) ΔrH°(298.15 K) = -39.3 ± 0.9 (×1.542) kJ/molVosper 1976, 2nd Law
0.0022000.1 ONN(O)O (g) H2O (g) → 2 HONO (g) ΔrH°(0 K) = 1.05 ± 0.30 (×1.756) kcal/molVarma 1976
0.0011999.7 NO (g) ONO (g) H2O (g) → 2 HONO (g) ΔrH°(298.15 K) = -9.55 ± 0.5 kcal/molWaldorf 1963, 2nd Law, est unc
0.0002000.2 ONN(O)O (g) H2O (g) → 2 HONO (g) ΔrH°(298.15 K) = 1.9 ± 1.2 (×2.954) kJ/molVosper 1976, 2nd Law
0.0001999.5 NO (g) ONO (g) H2O (g) → 2 HONO (g) ΔrH°(323 K) = -37.77 ± 0.65 (×4.757) kJ/molAshmore 1961, 2nd Law


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 21st 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.