Chem Catalyst How is an ion formed?

Today’s Agenda: 1. Do Now 2. Intro: New Chapter 3. Notes- Oxidation & Reduction 4. Practice Worksheet

New Topic: Electrochemistry Chapter 20 (and some Chapter 21) - Oxidation and Reduction - Writing Redox Reactions - Voltaic cells/batteries

Oxidation Reactions - Originally defined as combining the element with oxygen - Now defined as loss of electrons (shift of electrons away from an atom) - Charge becomes more positive (increases)

Reduction Reactions - Originally defined as removing oxygen from a compound with the element - Now defined as gain of electrons (shift of electrons toward an atom) - Charge becomes more negative (charge decreases) - Occurs alongside an oxidation reaction

Redox Reactions - A reaction that includes oxidation and reduction - The substance that gains electrons is reduced - The substance that loses electrons is oxidized - “LEO the lion goes GER” - Losing Electrons is Oxidation; Gaining Electrons is Reduction

Redox Reactions: Practice Identify the element being reduced and the element being oxidized: Hint: break apart the ionic compounds 2AgNO 3 + Cu  Cu(NO 3 ) 2 + 2Ag *Identify the oxidizing agent and the reducing agent

Redox Reactions: Practice Identify the element being reduced and the element being oxidized: 2Na + Br 2  2NaBr

Applications of Redox: - Some metals (gold, platinum) are not easily oxidized - Iron is oxidized by oxygen, causing corrosion - Can be coated w/ aluminum, whose oxide does not corrode - Connect to an easily oxidized metal (zinc, magnesium) which will transfer electrons to iron