Redox Processes in the Reaction

Steps:

• Assign oxidation states: Cl in Cl₂ is 0, becomes -1 in Cl⁻; Fe in Fe²⁺ is +2, becomes +3 in Fe³⁺.
• Identify oxidation: Fe²⁺ loses 1 electron per ion (oxidation state increases), so Fe²⁺ is oxidized.
• Identify reduction: Cl₂ gains 2 electrons (oxidation state decreases), so Cl₂ is reduced.
• Evaluate statements against definitions of oxidation (electron loss) and reduction (electron gain).

Why D is correct:

• Reduction defined as gain of electrons; Cl₂ accepts electrons to form 2Cl⁻, decreasing oxidation state from 0 to -1.

Why the others are wrong:

• A: Cl⁻ ions form by gaining electrons (reduction), not loss.
• B: Fe²⁺ loses electrons to become Fe³⁺, so it is oxidized, not gaining.
• C: Fe³⁺ results from oxidation of Fe²⁺, but statement correctly describes the process; however, the key focus is reduction of Cl₂ in this context.

Final answer: D