Electrochemistry

Nota:

• http://www.youtube.com/watch?v=C26pH8kC_Wk

1. Consist of two half cells
   1. Electrode immersed in electrolyte
      1. Through which ions move
   2. Connected to each other by a wire
      1. Through which electrons move
   3. Each electrolyte is connected by a salt bridge
      1. Through which ions move
   4. Oxidation / Reduction
      1. Oxidation
         1. Occurs at Anode
         2. Occurs at negative terminal
      2. Reduction
         1. Occurs at Cathode
         2. Occurs at positive terminal
2. Galvanic Cell
3. Reactions
   1. Anode
      1. Zn -> Zn2+ + 2e-
   2. Cathode
      1. Cu2+ + 2e- -> Cu
   3. Electrons travel through circuit in order to reach other half cell
      1. The more reactive metal will always give electrons
      2. The less reactive metal will always take electrons

1. Fuel Cells
   1. How they work
      1. Use Hydrogen and Oxygen
      2. Split hydrogen electrons from protons
      3. Then join them up on other side of curcuit
      4. Produce only water
   2. Positives
      1. Produce no harmful waste products
      2. Can theoretically go forever
      3. Allow us to attain power in far off locations
   3. Negatives
      1. Very Expensive
2. Electrolytic Cells
   1. Lead Car Battery
   2. Recharge through electrolysis
   3. Works like galvanic cell
   4. Recharging
      1. Lead Electrode: Pb2+ + 2e- → Pb
      2. Lead Oxide Electrode: Pb2+ → Pb4+ + 2e-