Question

$KMnO _4$ oxidises $I ^{-}$in acidic and neutral/faintly alkaline solution, respectively, to

• A. $IO _3^{-} \& IO _3^{-}$
• B. $I _2 \& IO _3^{-}$
• C. $I _2 \& I _2$
• D. $IO _3^{-} \& I _2$

Answer 1

Answer: (B)

In acidic medium
$2 MnO _4^{-}+10 I ^{-}+16 H ^{+} \rightarrow 2 Mn ^{2+}+5 I _2+8 H _2 O$
In neutral/faintly alkaline solution
$2 MnO _4^{-}+ I ^{-}+ H _2 O \rightarrow 2 MnO _2+2 OH ^{-}+ IO _3^{-}$