1. Electro-chemistry: Batteries and plating Electrochemistry: The study of the interchange of chemical and electrical energy Oxidation is the loss of electrons (Increase in charge). OIL Reduction is the gain of electrons (Decrease in charge) RIG

2. 2 metals and 2 solutions of the same metal (ions) The more active metal will LOSE electrons to the less active metal (it’s ions) which will GAIN Electrons You need:

3. Electrochemical Cells: 1.Voltaic Cells: Produces electrical current spontaneous chemical reactions  ex. Battery 2. Electrolytic Cells Consumes electrical current non-spontaneous and require electricity or battery  ex. Electrolysis, electroplating Device capable of either generating electrical energy from chemical reactions or facilitating chemical reactions through the introduction of electrical energy

4. Parts of the voltaic cell… Anode  the electrode where oxidation occurs After a period of time, the anode may appear to become smaller as it falls into solution. Cathode  the electrode where reduction occurs After a period of time it may appear larger, due to ions from solution plating onto it. Salt Bridge  a device used to maintain electrical neutrality in a voltaic cell. This may be filled with a salt solution. Electron Flow  always from anode to cathode (through the wire) Ion Flow  always through the salt bridge

5. Anode Cathode

6. Electricity can be made from a spontaneous redox reaction, instead of heat, light... 2 half cells 1 side loses electrons to the other side that gains Zinc metal Zn solution like ZnSO 4 (aq) The more active metal looses, higher on Chart J Copper metal Cu solution like CuSO 4 (aq) “ Dead” battery has reached equilibrium, volts = 0 e - ’s flows on wire Zn 0  Zn +2 + 2e - Cu +2 + 2e -  Cu 0 LEO anode GER cathode (also called electrochemical cells) measured in volts - ions flow in salt bridge 2 or more cells = a battery

7. Redox reactions that are not spontaneous and require electricity Electrolysis : splitting a chemical apart into its elements using electricity battery H2OH2O H 2 O  H 2 (g) + O 2 (g) + + H + + 1 e -  H 0 GER (cathode) O -2  O 0 + 2e - LEO (anode)

8. Electroplating : adding a layer of a metal onto another metal metal for plating fork to be plated solution with metal ions (usually expensive metals onto cheaper metal) Ag Ag + Ag + + 1e -  Ag 0 reduction cathode Ag 0  Ag +1 + 1 e - oxidation anode - + battery (Requires electricity or a battery) - - - -