Practice Problem: Balancing Redox Reactions

This tutorial guides students through the process of balancing redox reactions under acidic conditions. It begins with an introduction to redox reactions and proceeds to split the reaction into oxidation and reduction half reactions. The tutorial then covers balancing oxygen with water molecules and hydrogen with protons. Next, it explains how to balance charges using electrons. Finally, the tutorial demonstrates how to combine the half reactions to form a balanced equation.

What is the initial reaction given for balancing under acidic conditions?

• MnO4 plus Fe2 plus yields Mn2 plus plus Fe3 plus

• MnO4 minus plus Fe2 plus yields Mn3 plus plus Fe3 plus

• MnO4 minus plus Fe3 plus yields Mn2 plus plus Fe2 plus

• MnO4 minus plus Fe2 plus yields Mn2 plus plus Fe3 plus

Which element undergoes oxidation in the given reaction?

• Oxygen

• Hydrogen

• Iron

• Manganese

How many water molecules are needed to balance the oxygen atoms in the reduction half-reaction?

• Two

• Three

• Four

• Five

How many electrons are required to balance the charge in the reduction half-reaction?

• Four

• Three

• Six

• Five

What is the final balanced equation under acidic conditions?

• 5 Fe2 plus + MnO4 minus + 8 H plus yields 5 Fe3 plus + Mn2 plus + 4 H2O

• 5 Fe3 plus + MnO4 minus + 8 H plus yields 5 Fe2 plus + Mn2 plus + 4 H2O

• 5 Fe2 plus + MnO4 minus + 4 H2O yields 5 Fe3 plus + Mn2 plus + 8 H plus

• 5 Fe3 plus + Mn2 plus + 4 H2O yields 5 Fe2 plus + MnO4 minus + 8 H plus