In the reaction,
`IO_(3)^(-)+SO_(2)+4H_(2)O to I_(2)+SO_(4)^(2-)+8H^(+)`
The coefficient of `SO_(2)` is

Options

A. Three
B. Four
C. Five
D. Six

Answer

C

Explanation

Let the oxidation state of Mn is x:
(1) `KMnO_(4)+1x+(-2) xx 4=0`
x-7=0
x=+7
(2) `K_(2)MnO_(4)(+1) xx 2+x +(-2) xx 4=0`
x-6=0
x=+6
(3) `Mn_(2)O_(3) x xx 2+(-2) xx 3=0`
`2x=+6`
x=+3
(4) `MnO_(2) x+(-2) xx 2=0`
x=+$
Thus, oxidation state of Mn is highest in `KMnO_(4)`