Question

What is the oxidation number of Mn in MnSO4, KMnO4, and K2MnO4 ?

Answer 1

You gots `Mn(+II)` in `MnSO_4`...

Explanation:

And `Mn(VII+)` in `MnO_4^(-)`...`"permanganate ion"`

And `Mn(VI+)` in `MnO_4^(2-)`...`"manganate ion"`

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