Oxidation State The elements of group 13 have to two electrons in the s- orbital and one electron in the p-orbital of the valence shell. These elements are expected to show a uniform oxidation state of +3. Boron and aluminium which show an oxidation state of +3 only but gallium, indium and thallium due to inert pair effect show oxidation state of both +1 and +3 . As we … [Read more...] about Chemical Properties of Boron Family