Select the correct statements:

Options

A. Oxidation number of oxygen in `O_(2)^(+)` is + `1/2`
B. Oxidation number of oxygen in `O_2^(-)` is `-1/2`
C. Oxidation number of Cr in `K_(3)CrO_8` is +5
D. Average oxidation number of Br in tribromooctaoxide `(Br_(3)O_(8))` is `+18/3`

Answer

A, B, C

Explanation

In `Br_(3)O_8` two Br atoms have +6 oxidation number and one has +4.
The average oxidation no. id + `16/3`
`O=overset(O)overset(||)underset(O)underset(||)(" "Br^(+6))-overset(O)overset(||)underset(O)underset(||)(" "Br^(+4))-overset(O)overset(||)underset(O)underset(||)(" "Br^(+6))=O`