Answer:
The oxidation number of iron changes from 2+ to 0.
10 electrons are transferred in the reaction.
Step-by-step explanation:
Step 1: Write the balanced redox reaction
5 Fe²⁺ + 2 Mn²⁺ + 8 H₂O ⇒ 2 MnO₄⁻ + 5 Fe + 16 H⁺
Step 2: identify both half-reactions
Reduction: 5 Fe²⁺ + 10 e⁻ ⇒ 5 Fe
Oxidation: 2 Mn²⁺ + 8 H₂O ⇒ 2 MnO₄⁻ + 16 H⁺ + 10 e⁻
Step 3: Identify the oxidation state change of iron
Iron changes from Fe²⁺ to Fe, that is, the oxidation number changes from 2+ to 0.
Step 4: Determine how many electrons are transferred in the reaction?
According to both balanced half-reactions, 10 electrons are transferred in the reaction.