In chemistry, the perbromate ion is the anion with the chemical formula . It is an oxyanion of bromine, the conjugate base of perbromic acid, in which bromine has the oxidation state +7. Unlike its chlorine () and iodine () analogs, it is difficult to synthesize. Later, it was obtained by the oxidation of bromate with xenon difluoride. Once perbromates are obtained, perbromic acid can be produced by protonating .
In 2011 a new, more effective synthesis was discovered: perbromate ions were formed through the reaction of hypobromite and bromate ions in an alkaline sodium hypobromite solution. The reaction (and its perchlorate analogue) occurs naturally, but very slowly, requiring several days to complete.
See also
Other bromine anions:
{| class="wikitable"
|-
! Bromine oxidation state
| −1
| +1
| +3
| +5
| +7
|-
! Name
| bromide
| hypobromite
| bromite
| bromate
| perbromate
|-
! Formula
| Br<sup>−</sup>
| BrO<sup>−</sup>
|
|
|
|-
! Structure
| 50px|The bromide ion
| 50px|The hypobromite ion
| 50px|The bromite ion
| 50px|The bromate ion
| 50px|The perbromate ion
|}