<h2>Answer:</h2><h3>Part 1. </h3>
Option B is correct option.
The half-reaction 2MnO2 + H2O + 2e- Mn2O3 is missing OH- ions.
Explanation:
Full equation:
2MnO2 + H2O + 2e- → Mn2O3 + 2OH-
<h3>Part 2:</h3>
The option B which is Mg is stronger reducing agent than Ag is correct option.
Explanation:
Equation:
Mg(s) + 2Ag+ (aq) → Mg2+ (aq) + 2Ag(s)
According to equation Mg converts to Mg+2 which means it gives to electron to reduce Ag. So it act as an reducing agent.
<h3>Part 3:</h3>
The correct option is B. Which is 5, 1, 8, 5, 1, 4.
Explanation:
Full equation :
5 Fe²⁺ (aq) + MnO₄⁻ (aq) + 8 H⁺ (aq) --> 5 Fe³⁺ (aq) + Mn²⁺ (aq) + 4 H₂O (l)
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