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NTA Abhyas JEE Main2020Chemistryd and f Block ElementsPractice

When MnO 2 is fused with KOH and KNO 3 , a coloured compound is formed. Choose the right compound with the appropriate colour.

Options

  1. AK 2 MnO 4 , green
  2. BKMnO 4 , purple
  3. CMn 2 O 3 , brown
  4. DMn 3 O 4 , black

Correct answer

A. K 2 MnO 4 , green

Step-by-step solution

When MnO 2 reacts with fused mixture of KOH and KNO 3 , it forms K 2 MnO 4  (Green compound) as follows: MnO 2 + KNO 3 + 2   KOH → Δ K 2 MnO 4 green + KNO 2 + H 2 O

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