REDOX REACTIONS

Oxidation-Reduction reactions• A reaction in which electrons are transferred from one atom to another

• Chemists often refer to oxidation-reactions as redox reactions

• Example: • Complete chemical equation: • 2 KBr (aq) + Cl2 (aq) 2 KCl (aq) + Br2 (aq)• Net ionic Equation: 2Br- (aq) + Cl2 (aq) Br2 (aq) + 2 Cl-

Vocabulary• Half reactions- part of the redox reaction where it shows either

the oxidation reaction or the reduction reaction• Electrons are usually present in either side of the half reaction• Oxidation half-reactions has electrons on the product side (losing

electrons)• Reduction half-reactions has electrons on the reactant side (gaining

electrons)

• Oxidizing agent- a chemical species that Accepts (gains) electrons from an oxidized species• Reducing species = Oxidizing agent

• Reducing agent- a chemical species that Donates (lose) electrons from a reduced species• Oxidizing species = Reducing agent

Oxidation Reactions• Oxidation is defined as the loss of electrons from atoms of a substance• Reactions that LOSE ELECTRONS (LEO- “Loss of Electrons”-Oxidation)

Reduction Reactions• Reactions that GAIN ELECTRONS (GER- “Gaining Electrons- Reduction)

Practice: • Identify as oxidation or reduction

1. Al → Al3+ + 3e-

2. Cu2+ + e- → Cu+

3. Fe3+ → Fe2+