What is the common oxidation number of bromine in its compounds?

1 Answer
Aug 3, 2015

Answer:

Usually #-I#, but not always.

Explanation:

As a halogen, bromine commonly exhibits a #-I# oxidation state (i.e. valency) in its ionic compounds as the bromide anion, but it does not do so exclusively. Bromine does form so-called interhalogen compounds, e.g #BrF_3#, or even #BrF# (and what is the formal oxidation state of #Br# in these two examples; they are different in each case). Oxidation numbers of #+I#, #+III#, #+V#, and #+VII# are known with its oxides, and oxoanions.

Both valency and oxidation number are of course a formalism; can you assign the oxidation number of bromine in its elemental state?