1. Warm Up 5/15/18 1. Label both half reactions as oxidized or reduced
2. Determine the net ionic equation and how many moles were transferred
3. Calculate the cell potential
5/17
Electrochemistry review due
5/18
Last day to turn in mole $
Last day for Thermochem corrections and retest
Electrochem test

2. Voltaic (Galvanic) and Electrolytic Cells

3. Voltaic (Galvanic) and Electrolytic Cells
Electrochemical cells: a device capable of producing electrical energy from chemical reactions (voltaic/galvanic) or facilitating chemical reactions through the introduction of electrical energy (electrolytic).
Voltaic/galvanic cells: use thermodynamically favorable reactions to produce electricity.
Electrolytic cells: use electricity to drive thermodynamically unfavorable reactions.
Half-cells: a compartmentalized cell comprised of an electrode and a solution where either reduction OR oxidation occurs (only one!!!).
Must be paired with the opposite reaction type (reduction OR oxidation) to form a full electrochemical cell.

4. Voltaic (Galvanic) and Electrolytic Cells
Anode: where the oxidation reaction occurs (electrons being lost).
Cathode: where the reduction reaction occurs (electrons being gained).
Must have BOTH an anode and cathode!!!
voltmeter e-
cathode
anode
Note: The anode is not always the electrode on the left!

5. Voltaic (Galvanic) and Electrolytic Cells
How can you remember which reaction occurs where?
An Ox
Red Cat
How can you remember how electrons move through the wire?
FAT CAT
hode
rom
node o

6. Voltaic (Galvanic) and Electrolytic Cells
How can you remember which electrode loses mass and which gains mass?
FAT CAT
voltmeter e-
hode
cathode
anode
Lose mass
Gain mass

7. Voltaic (Galvanic) and Electrolytic Cells
Salt bridge: soaked with a solution containing a dissolved ionic solute (positive and negative charges) and connects the two half cells
As the cell runs, the negative ions move towards the anode (since negative electrons are being lost) and the positive ions move towards the cathode (since negative electrons are being gained).
This is to balance out the charges in each cell so neither positive nor negative charges build up in a half- cell.
Free electrons do NOT move across the salt bridge.
voltmeter e- - +
cathode
anode
ion
ion
Lose mass
Gain mass

8. Voltaic (Galvanic) and Electrolytic Cells
Calculate the Eocell of the electrochemical cell using: Eocell = Eored + Eoox
Voltmeter: measures the voltage (Eocell) of an electrochemical cell.
Standard condtions: 1 M solutions, 1 atm gases, and 298 K.