What will be oxidation number of sulphur in `S_2O_(8)^(2-)` ion and `S_(4)O_(6)^(2-)` ion ?

Explanation

(I) In `S_2O_(8)^(2-)`, there is one peroxide bond `(-O-O-)` therefore , two oxygen atoms having oxidation number `-1` (i.e., `O_(2)^(2-)`) and for the other six oxygen atoms. The oxidation number is -2.
`S_2O_(8)^(2-)=2x+(-2+6)+(-1xx2)=-2`
`2x=+12rArr x=+6`

(II) In `S_(4)O_(6)^(2-)`, two S-atoms have oxidation state `+5` while another two S-atoms have 0 oxidation state.