When $\mathrm{M}\mathrm{n}{\mathrm{O}}_4^{2-}$ (1 mole) in neutral aqueous medium is disproportionate, the product obtained is

• Correct answer
  A

  2/3 mole of $\mathrm{M}\mathrm{n}{\mathrm{O}}_4^{-}$ and 1/3 mole of $\mathrm{M}\mathrm{n}{\mathrm{O}}_2$
• B

  1/3 mole of $\mathrm{M}\mathrm{n}{\mathrm{O}}_4^{-}$ and 2/3 mole of $\mathrm{M}\mathrm{n}{\mathrm{O}}_2$
• C

  1/3 mole of $\mathrm{M}{\mathrm{n}}_2{\mathrm{O}}_7$ and 1/3 mole of $\mathrm{M}\mathrm{n}{\mathrm{O}}_2$
• D

  2/3 mole of $\mathrm{M}{\mathrm{n}}_2{\mathrm{O}}_7$ and 1/3 mole of $\mathrm{M}\mathrm{n}{\mathrm{O}}_2$

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