Iodite

The iodite ion, or iodine dioxide anion, is the halite with the chemical formula IO⁻
₂. Within the ion, the iodine exists in the oxidation state of +3.

Iodite

Names
IUPAC name iodite
Systematic IUPAC name dioxidoiodate(1−)
Identifiers
CAS Number	20499-55-2
3D model (JSmol)	Interactive image
ChemSpider	4574132
PubChem CID	5460637
CompTox Dashboard (EPA)	DTXSID901031417
InChI InChI=1S/HIO2/c2-1-3/h(H,2,3)/p-1
SMILES [O-][I+][O-]
Properties
Chemical formula	IO− 2
Molar mass	58.90 g/mol
Conjugate acid	Iodous acid
Related compounds
Other anions	Chlorite Bromite
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Iodite anion

Iodites (including iodous acid) are highly unstable and have been observed^[1] but never isolated.^{[citation needed]} They will rapidly disproportionate to molecular iodine and iodates.^[2] However, they have been detected as intermediates in the conversion between iodide and iodate.^[3][4]

Other oxyanions

Iodine can assume oxidation states of −1, +1, +3, +5, or +7. A number of neutral iodine oxides are also known.

Iodine oxidation state	−1	+1	+3	+5	+7
Name	iodide	hypoiodite	iodite	iodate	periodate
Formula	I−	IO−	IO− 2	IO− 3	IO− 4 or IO5− 6