Balance the skeleton equation MnO₄⁻ + Fe²⁺ + H⁺ → Mn²⁺ + Fe³⁺ + H₂O. The coefficient of MnO₄⁻ is:
A1
B2
C3
D5
Answer & Solution
Correct answer: A. 1
1. Mn: +7 → +2 (gain 5 e⁻); Fe: +2 → +3 (lose 1 e⁻).
2. Multiply Fe half by 5 to balance electrons.
3. Balanced: MnO₄⁻ + 5 Fe²⁺ + 8 H⁺ → Mn²⁺ + 5 Fe³⁺ + 4 H₂O.
4. Coefficient of MnO₄⁻ is 1.
_Source: NCERT Class 11 Chem Ch 8 §8.3 Balancing Redox Equations_
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