Peroxo nitric acid

Structural formula
General
Surname	Peroxo nitric acid
other names	Peroxysnitric acid
Molecular formula	ENT 4
External identifiers / databases
CAS number 26404-66-0 PubChem 65357 ChemSpider 58833 Wikidata Q1285205
properties
Molar mass	79.01 g mol −1
safety instructions
GHS hazard labeling no classification available
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

The Peroxosalpetersäure is an oxygen acid of nitrogen with the molecular formula NO ₂ (OOH) = ENT ₄ . The very unstable compound is counted among the photo-oxidants .

Manufacturing

Peroxo nitric acid can be produced in the laboratory by the action of dry hydrogen peroxide (H ₂ O ₂ ) on crystalline nitrous pentoxide (N ₂ O ₅ , the anhydride of nitric acid ) at a temperature of −80 ° C:

${\displaystyle \mathrm {N_{2}O_{5}+H_{2}O_{2}\longrightarrow NO_{2}(OOH)+HNO_{3}} }$

Due to its high instability, it disintegrates explosively at −30 ° C. As a weakly concentrated solution, it can be kept for some time at 20 ° C, but then breaks down into H ₂ O ₂ and HNO ₃ . At pH values > 5, the peroxonitrate ion breaks down into a nitrite ion and an oxygen molecule :

${\displaystyle \mathrm {NO_{4}^{-}\longrightarrow NO_{2}^{-}+O_{2}} }$

Occurrence in nature

Intensive solar radiation in the earth's atmosphere can lead to the (short-term) formation of peroxo-nitric acid through the reaction of nitrogen dioxide (NO ₂ ) with a HOO radical :

${\displaystyle \mathrm {HOO\cdot +NO_{2}\longrightarrow NO_{2}(OOH)} }$

Because of its instability, it also disintegrates in turn and reacts to the products described above, among other things.

Individual evidence

1. ↑ This substance has either not yet been classified with regard to its hazardousness or a reliable and citable source has not yet been found.
2. ↑ ^{a b} Ralf Steudel : Chemistry of Non-Metals From Structure and Bond to Application . Walter de Gruyter, 2008, ISBN 978-3-11-021128-3 , p. 350 ( limited preview in Google Book Search).
3. ↑ Erwin Riedel, Christoph Janiak: Inorganic Chemistry . Walter de Gruyter, 2011, ISBN 978-3-11-022566-2 , p. 485 ( limited preview in Google Book search).
4. ↑ Detlev Möller: Air chemistry, physics, biology, cleanliness, law . Walter de Gruyter, 2003, ISBN 978-3-11-016431-2 , p. 355 ( limited preview in Google Book Search).

See also

• Nitrogen oxides