What is the balanced redox reaction for Cl2(g) + Mn2+(aq) → MnO2(s) + Cl-(aq) in a basic solution?

• A. Cl2(g) + Mn2+(aq) + 4OH-(aq) → MnO2(s) + Cl-(aq) + 2H2O(l)
• B. Cl2(g) + Mn2+(aq) + 2H2O(l) → MnO2(s) + 2Cl-(aq) + 2OH-(aq)
• C. Cl2(g) + Mn2+(aq) + 2OH-(aq) → MnO2(s) + 2Cl-(aq) + H2O(l)
• D. Cl2(g) + 2Mn2+(aq) + 4OH-(aq) → 2MnO2(s) + 2Cl-(aq) + 2H2O(l)

Answer: (C)

Verified step by step guidance

1. Identify the oxidation and reduction half-reactions. Chlorine (Cl2) is reduced to chloride ions (Cl-), and manganese ions (Mn2+) are oxidized to manganese dioxide (MnO2).
2. Write the reduction half-reaction for chlorine: Cl2(g) → 2Cl-(aq). Balance the atoms and charges by adding electrons: Cl2(g) + 2e- → 2Cl-(aq).
3. Write the oxidation half-reaction for manganese: Mn2+(aq) → MnO2(s). Balance the oxygen atoms by adding water molecules: Mn2+(aq) + 2H2O(l) → MnO2(s). Balance the hydrogen atoms by adding hydroxide ions: Mn2+(aq) + 2H2O(l) → MnO2(s) + 4OH-(aq). Balance the charges by adding electrons: Mn2+(aq) + 2H2O(l) → MnO2(s) + 4OH-(aq) + 2e-.
4. Combine the balanced half-reactions. Ensure that the number of electrons lost in the oxidation half-reaction equals the number of electrons gained in the reduction half-reaction. Add the two half-reactions: Cl2(g) + 2e- + Mn2+(aq) + 2H2O(l) → 2Cl-(aq) + MnO2(s) + 4OH-(aq) + 2e-.
5. Cancel out the electrons and any other species that appear on both sides of the equation. The final balanced redox reaction in a basic solution is: Cl2(g) + Mn2+(aq) + 2OH-(aq) → MnO2(s) + 2Cl-(aq) + H2O(l).