Question

In a mildly alkaline medium, thiosulphate ion is oxidized by $KMn{O}_4$ to "A". The oxidation state of sulphur in "A" is:

Answer 1

In a mildly alkaline medium, thiosuphate is quantitavely oxidized by $KMn{O}_4$ to $S{O}_4^{2-}$
$8Mn{O}_4^{-}+3S_2{O}_3^{2-}+H_{2}O\to 8Mn{O}_2+6S{O}_4^{2-}+2O{H}^{-}$

"A" $\to S{O}_4^{2-}$

Oxidation number of ${}^{\prime }{S}^{\prime }=+6$.