Q9 of 47 Page 1

How is KMnO4 prepared from pyrolusite ? Give steps involved withequations.


Pyrolusite is nothing but manganese dioxide (MnO2).


First, MnO2 is oxidised in presence of KOH to give potassium manganite (K2MnO4) which is further reacted with HCl acid to give the desired KMnO4. The reactions involved are:


(i)


(ii)


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