# How do you name "HBr" and "HBrO"_3?

Oct 20, 2016

A good way to figure this out is that "hydro" implies that the anion does not have an oxygen atom, and that you can analogize with the chlorine-based acids that you were probably given.

For example:

$\text{HCl}$: hydrochloric acid
$\text{HClO}$: hypochlorous acid
${\text{HClO}}_{2}$: chlorous acid
${\text{HClO}}_{3}$: chloric acid
${\text{HClO}}_{4}$: perchloric acid

None of the acids above that contain oxoanions (such as ${\text{ClO}}_{3}^{-}$, or ${\text{ClO}}_{4}^{-}$) have "hydro" in their name.

Furthermore, the halogens all form acids with similar names because they are all in the same group/family. So, they have analogous acid naming schemes:

$\text{HBr}$: hydrobromic acid
$\text{HCl}$: hydrochloric acid
$\text{HI}$: hydroiodic acid

From this, you should be able to figure out that you have:

$\text{HBr}$: hydrobromic acid
${\text{HBrO}}_{3}$: bromic acid