The oxidation states not shown by Mn in given reaction is : $3 \mathrm{MnO}_4^{2-}+4 \mathrm{H}^{+} \longrightarrow 2 \mathrm{MnO}_4^{-}+\mathrm{MnO}_2+2 \mathrm{H}_2 \mathrm{O}$ A. +6 B. +2 C. +4 D. +7 E. +3 Choose the most appropriate answer from the options given below :

• A

  D and E only
• B

  B and D only
• C

  A and B only
• Correct answer
  D

  B and E only

Solution

In the following reaction $3 \mathrm{MnO}_4^{2-}+4 \mathrm{H}^{+} \longrightarrow 2 \mathrm{MnO}_4^{-}+\mathrm{MnO}_2+2 \mathrm{H}_2 \mathrm{O}$
So +2 and +3 oxidation state is not shown by Mn .

Hence, the correct answer is option: 'D'.