Question #f98b4

1 Answer
Oct 6, 2015

+7

Explanation:

The oxidation number for oxygen is always #-2# except in hydrogen peroxide it is #-1# and #OF_2# it is +2.

Having said that, the oxidation number of Mn in #MnO_4^_# is +7. It is calculated as follows:
#x+4xx(-2)=-1=>x=+7#