Respuesta :
Answer
2MnO₄⁻(aq) + 10Cl⁻(aq) + 16H⁺ → 2Mn²⁺(aq) + 5Cl₂(g) + 8H₂O
Explanation
What is given:
The following reaction takes place in an acidic solution:
MnO₄⁻(aq) + Cl⁻(aq) → Mn²⁺(aq) + Cl₂(g) (unbalanced).
What to find:
To identify the half-reactions and balance the redox reaction.
Step-by-step solution:
Step 1: Identify the half-reactions.
The oxidation half-reaction is: Cl⁻(aq) → Cl₂(g)
The reduction half-reaction is: MnO₄⁻(aq) → Mn²⁺(aq)
Step 2: Balance the equations for atoms (except O and H).
Oxidation: 2Cl⁻(aq) → Cl₂(g)
Reduction: MnO₄⁻(aq) → Mn²⁺(aq)
Step 3: Balance the equations for atoms O and H using H₂O and H⁺.
Oxidation: 2Cl⁻(aq) → Cl₂(g)
Reduction: MnO₄⁻(aq) + 8H⁺ → Mn²⁺(aq) + 4H₂O
Step 4: Balance the charge in the half-reactions.
Oxidation: 2Cl⁻(aq) → Cl₂(g) + 2e⁻
Reduction: MnO₄⁻(aq) + 8H⁺ + 5e⁻ → Mn²⁺(aq) + 4H₂O
Step 5: Multiply each half-reaction by the proper number to balance charges in the reaction.
Oxidation: 2Cl⁻(aq) → Cl₂(g) + 2e⁻ x 5
Reduction: MnO₄⁻(aq) + 8H⁺ + 5e⁻ → Mn²⁺(aq) + 4H₂O x 2
↓
Oxidation: 10Cl⁻(aq) → 5Cl₂(g) + 10e⁻
Reduction: 2MnO₄⁻(aq) + 16H⁺ + 10e⁻ → 2Mn²⁺(aq) + 8H₂O
Step 6: Add the equations and simplify to get a balanced equation.
2MnO₄⁻(aq) + 10Cl⁻(aq) + 16H⁺ + 10e⁻ → 2Mn²⁺(aq) + 5Cl₂(g) + 8H₂O + 10e⁻
Simplifying the equation, we have:
2MnO₄⁻(aq) + 10Cl⁻(aq) + 16H⁺ → 2Mn²⁺(aq) + 5Cl₂(g) + 8H₂O
