Chapter 12. Redox Reactions and Electrochemistry

Oxidation is loss of electrons (OIL); reduction is gain (RIG). Track change using oxidation numbers. The oxidizing agent is reduced; the reducing agent is oxidized.

Balancing in acidic solution (half-reaction method): balance atoms other than O and H, then O with H₂O, H with H⁺, charge with e⁻, and equalize electrons before adding [1][3].

Galvanic cells convert chemical energy to electrical energy: oxidation at the anode, reduction at the cathode. E°cell = E°cathode − E°anode. Relationships: ΔG° = −nFE° and the Nernst equation E = E° − (RT/nF) ln Q, with F = 96,485 C/mol [4][5].

Electrolysis uses external current to drive nonspontaneous reactions; Faraday’s laws relate charge to moles of product.

Review: Identify the oxidizing agent in Zn + Cu²⁺ → Zn²⁺ + Cu.