Nitrous acid
- Formula: HNO2
- Molecular weight: 47.0134
- IUPAC Standard InChI: InChI=1S/HNO2/c2-1-3/h(H,2,3)
- IUPAC Standard InChIKey: IOVCWXUNBOPUCH-UHFFFAOYSA-N
- CAS Registry Number: 7782-77-6
- Chemical structure:
This structure is also available as a 2d Mol file or as a computed 3d SD file
The 3d structure may be viewed using Java or Javascript. - Other names: HNO2; Kyselina dusite; Nitrosyl hydroxide; Nitrous acid, trans; HONO
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Reaction thermochemistry data
Go To: Top, References, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Data compiled as indicated in comments:
B - John E. Bartmess
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. A general reaction search form is also available. Future versions of this site may rely on reaction search pages in place of the enumerated reaction displays seen below.
Individual Reactions
+
=
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 1423.5 ± 0.88 | kJ/mol | D-EA | Ervin, Ho, et al., 1988 | gas phase; B |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrG° | 1396.3 ± 1.3 | kJ/mol | H-TS | Ervin, Ho, et al., 1988 | gas phase; B |
+
= (
•
)
By formula: NO2- + HNO2 = (NO2- • HNO2)
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 136. ± 4.2 | kJ/mol | TDAs | Lee, Keesee, et al., 1980 | gas phase; B |
+
=
+
By formula: C8H11N + HNO2 = C8H10N2O + H2O
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | -78.83 | kJ/mol | Cm | Swientoslawski, 1910 | liquid phase; ALS |
+
=
+
By formula: C12H11N + HNO2 = H2O + C12H10N2O
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | -62.84 | kJ/mol | Cm | Swientoslawski, 1910 | solid phase; ALS |
References
Go To: Top, Reaction thermochemistry data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Ervin, Ho, et al., 1988
Ervin, K.M.; Ho, J.; Lineberger, W.C.,
Ultraviolet Photoelectron Spectrum of NO2-,
J. Phys. Chem., 1988, 92, 19, 5405, https://doi.org/10.1021/j100330a017
. [all data]
Lee, Keesee, et al., 1980
Lee, N.; Keesee, R.G.; Castleman, A.W., Jr.,
The properties of clusters in the gas phase. IV. Complexes of H2O and HNOx clustering on NOx-,
J. Chem. Phys., 1980, 72, 1089. [all data]
Swientoslawski, 1910
Swientoslawski, W.,
Thermochemische Untersuchungen der organischen Verbindungen. Dritte Mitteilung. Stickstoffhaltige Verbindungen.,
Z. Phys. Chem., 1910, 72, 49-83. [all data]
Notes
Go To: Top, Reaction thermochemistry data, References
- Symbols used in this document:
ΔrG° Free energy of reaction at standard conditions ΔrH° Enthalpy of reaction at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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