Question

Potassium manganate `(K_2MnO_4)` is formed . When:
A. Cuprous oxide reacts with alkaline `KMnO_4` solution
B. Manganese dioxide is fused with `K_2CO_3` in presence of `KNO_3`
C. Formaldehyde reacts with potassium permanganate in presence of concentrated potassium hydroxide solution
D. Potassium permanganate is heated with potassium hydroxide

Answer 1

Correct Answer - A,B,C,D
(A)`KMnO_4 +Cu_2O + KOH to 2Cu(OH)_2 + K_2MnO_4`
(B)`2MnO_2 + 2K_2CO_3 + O_2 ("from" KNO_3) to 2K_2MnO_4 + 2CO_2`
(C )`HCHO + 2KMnO_4 + 2K_2MnO_4 + H_2O +HCOOH`
(D)`4KMnO_4+4KOH oversetDeltato4K_2MnO_4 +2H_2O + O_2`