Bromite

Bromous acid

Names
IUPAC names hydroxy-λ3-bromanone hydroxidooxidobromine bromous acid
Identifiers
3D model (Jmol)	Interactive image
ChEBI	CHEBI:29247 Y
ChemSpider	145144 Y
PubChem CID	165616
InChI InChI=1S/BrHO2/c2-1-3/h(H,2,3) Y Key: DKSMCEUSSQTGBK-UHFFFAOYSA-N Y InChI=1/BrHO2/c2-1-3/h(H,2,3) Key: DKSMCEUSSQTGBK-UHFFFAOYAC
SMILES O=BrO
Properties
Chemical formula	HBrO2
Molar mass	112.911 g/mol
Related compounds
Other anions	Hydrobromic acid; hypobromous acid; bromic acid; perbromic acid
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Y  (what is YN ?)
Infobox references

Bromous acid is the inorganic compound with the formula of HBrO₂. It is an unstable compounds, although salts of its conjugate base - bromites - have been isolated. In acidic solution, bromites decompose to bromine.

In 1905, Richards A. H. proved the existence of bromous acid through a series of experiments involving silver nitrate (AgNO₃) and bromine. The reaction of excess cold aqueous to form hypobromous acid (HBrO), silver bromide (AgBr) and nitric acid (HNO₃):

Richards discovered that the effect of adding excess liquid bromide in a concentrated silver nitrate (AgNO₃) resulted in a different reaction mechanism. From numbers of equivalent portions of acid-bromine formed from the previous reaction, the ratio between oxygen and bromine was calculated, with the exact value of O: Br (0.149975: 0.3745), suggesting the acid compound contains two oxygen atom to one bromine atom. Thus, the chemical structure of the acid compound was deducted as HBrO₂.

According to Richards, hypobromous acid (HBrO) arises by the reaction of bromine and silver nitrate solution:

The molecule HBrO₂ has a bent structure with ∠(H−O−Br) angles of 106.1^o. HOBrO also adopts a non-planar conformation with one isomer structure (2a) adopts a with dihedral angle ∠(H−O−Br− O) of 74.2°. Moreover, the planar structures of two other isomers (2b - cis and 2c - trans) are transition state for fast enantiomerization.

Another study identified three isomers: HOOBr, HOBrO, and HBr(O)O.

A oxidation reaction between hypobromous acid (HBrO) and hypochlorous acid (HClO) can be used to produce bromous acid (HBrO₂) and hydrochloric acid (HCl).

A redox reaction of hypobromous acid (HBrO) can form bromous acid (HBrO₂) as its product:

The disproportion reaction of two equivalents hypobromous acid (HBrO) results in the formation of both bromous acid (HBrO₂) and bromic acid (HBr):