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, Gas phase ion energetics data, 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° | 340.23 ± 0.21 | kcal/mol | D-EA | Ervin, Ho, et al., 1988 | gas phase; B |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrG° | 333.73 ± 0.31 | kcal/mol | H-TS | Ervin, Ho, et al., 1988 | gas phase; B |
+
= (
•
)
By formula: NO2- + HNO2 = (NO2- • HNO2)
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 32.5 ± 1.0 | kcal/mol | TDAs | Lee, Keesee, et al., 1980 | gas phase; B |
+
=
+
By formula: C8H11N + HNO2 = C8H10N2O + H2O
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | -18.84 | kcal/mol | Cm | Swientoslawski, 1910 | liquid phase; ALS |
+
=
+
By formula: C12H11N + HNO2 = H2O + C12H10N2O
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | -15.02 | kcal/mol | Cm | Swientoslawski, 1910 | solid phase; ALS |
Gas phase ion energetics data
Go To: Top, Reaction thermochemistry data, 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
LL - Sharon G. Lias and Joel F. Liebman
Ionization energy determinations
| IE (eV) | Method | Reference | Comment |
|---|---|---|---|
| ≤11.3 | DER | Lias, Bartmess, et al., 1988 | LL |
De-protonation reactions
+
=
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 340.23 ± 0.21 | kcal/mol | D-EA | Ervin, Ho, et al., 1988 | gas phase; B |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrG° | 333.73 ± 0.31 | kcal/mol | H-TS | Ervin, Ho, et al., 1988 | gas phase; B |
References
Go To: Top, Reaction thermochemistry data, Gas phase ion energetics 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]
Lias, Bartmess, et al., 1988
Lias, S.G.; Bartmess, J.E.; Liebman, J.F.; Holmes, J.L.; Levin, R.D.; Mallard, W.G.,
Gas-phase ion and neutral thermochemistry,
J. Phys. Chem. Ref. Data, Suppl. 1, 1988, 17, 1-861. [all data]
Notes
Go To: Top, Reaction thermochemistry data, Gas phase ion energetics 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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