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Most Important Selected Qs for JEE AdvancedChemistryd and f Block Elements

Pyrolusite is MnO ₂ used to prepare KMnO ₄ . Steps are, MnO ₂ I MnO ₄ ²⁻ II MnO ₄⁻ . Steps I and II are respectively:

Options

  1. Afuse with KOH / air and electrolytic oxidation.
  2. Bfuse with KOH / KNO ₃ and electrolytic oxidation.
  3. Cfuse with conc. HNO ₃ / air and electrolytic reduction.
  4. Ddissolve in H ₂ O and oxidation.

Correct answer

B. fuse with KOH / KNO ₃ and electrolytic oxidation.

Step-by-step solution

Fuse with KOH in presence of air or oxidising agents like KNO ₃ , KClO ₃ etc. aligned & 2 MnO ₂+4 KOH + O ₂ fuse 2 ~K ₂ MnO ₄+2 H ₂ O & MnO ₄ ²⁻ electrolytic oxidation MnO ₄⁻+ e ⁻ aligned

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