Find out the oxidation number (O.N.) of S in (a) `H_(2)S` (b) `SO_(2)` (c) `SO_(3)` (d) `SO_(3)^(2-)`.

Explanation

(a) O.N. of S in `H_(2)S : underset((2xx1))(H_(2))S:.x+2=0orx=-2`
(b) O.N. of S in `SO_(2):underset((x))(S)underset((-2xx2))(O_(2)):.x-4=0orx=+4`
(c) O.N of S in `SO_(3):underset((x))(S)underset((-2xx3))(O_(3)):.x-6=0orx=+6`
(d) O.N. of S in `SO_(3)^(2-):underset((x))(S)underset((-2xx3))(O_(3)^(2-)):.x-6=-2orx=-2+6orx=+4`.