Question

Which of the following will not be oxidized by ozone ?

• A. $KI$
• B. $FeSO_4$
• C. $KMnO_4$
• D. $K_2MnO_4$

Answer 1

Answer: (C)

$KMnO_4$

Answer 2

$KMnO_{4}$ cannot be further oxidized by $O_{3}$. It has the highest $+7$ oxidation state of Mn in it. Alkaline $KI$ is oxidised to potassium iodate and periodate. $KI+3O_{3} \to \underset{\text{Pot. iodate}}{{KIO_{3}}}+3O_{2}$ $KI+4O_{3} \to \underset{\text{Pot. periodate}}{{KIO_{4}}}+4O_{2}$ It oxidises manganate to permanganate $2K_{2}MnO_{4} + H_{2}O+O_{3} \to 2KMnO_{4}+2KOH+O_{2}$ Acidified ferrous sulphate is oxidized to ferric sulphate $2FeSO_{4}+H_{2}SO_{4}+O_{3} \to Fe_{2} (SO_{4})_{3} + H_{2}O+O_{2}$