Question

The formulae of two compounds of manganese are MnO2 and KMnO4. What are the oxidation state of manganese in each of these two compounds?

( oxidation state of K: +1 oxidation state of oxygen: -2 )

Answer 1

The oxidation state of manganese in MnO2 is +4 and in KMnO4 is +7. This can be determined by using the oxidation states of K (+1) and oxygen (-2) in KMnO4 and the fact that the sum of the oxidation states of all the elements in a neutral compound must be zero. Since there are four oxygen atoms in KMnO4, their total contribution to the oxidation state is -8. To balance this, the oxidation state of manganese must be +7, which means it has been oxidized from +4 in MnO2 to +7 in KMnO4.

Step-by-step explanation: