1. CHAPTER 16 (pages 776-792) Oxidation and Reduction
Galvanic Cells, Half Reactions (E°anode & E°cathode)
Standard Reduction Potential (E°)
Nernst Equation, and the dependence of Potential on Concentration
Relationship between Equilibrium Constant and Standard Potential
Driving Force, ΔG and E

2. REDOX REACTIONS MnO2 + 4 HBr ⇋ MnBr2 + Br2 + 2 H2O
3 H2S + 2 NO3– H+ ⇋ 3 S + 2 NO + 4 H2O

3. OBSERVED REDOX PROCESSES

4. GALVANIC CELLS

5. INERT ELECTRODES

6. STANDARD REDUCTION POTENTIALS

8. MEASURING STANDARD POTENTIALS

9. CALCULATING STANDARD CELL POTENTIAL
Al(s) + NO3−(aq) + 4 H+(aq) ⇋ Al3+(aq) + NO(g) + 2 H2O(l)

10. ADDITIONAL EXAMPLE
Fe(s) + Mg2+(aq) ⇋ Fe2+(aq) + Mg(s)

11. ox: Fe(s)  Fe2+(aq) + 2 e− E = +0.45 V
red: Pb2+(aq) + 2 e−  Pb(s) E = −0.13 V
tot: Pb2+(aq) + Fe(s)  Fe2+(aq) + Pb(s) E = V

12. ELECTROMOTIVE POTENTIAL

13. Figure: UN
Title:
Thermodynamic terms, with equations
Caption:
Cell potential, free energy, and the equilibrium constant are all related.

14. E°CELL, ΔG° AND K
Under standard state conditions, a reaction will spontaneously proceeds in the forward direction if:
ΔG° < 1 (negative)
E° > 1 (positive)
K > 1

15. Design a voltaic cell with the following half
cells and complete the calculations:
Ag+ (aq) + 1e-  Ag (s) Eo = 0.80 V
Pb2+ (aq) + 2e-  Pb (s) Eo = V
Calculate the Eocell (potential at standard conditions)
Calculate Go.
Calculate 
Calculate the Ecell if [Ag+] = 2.0 M and [Pb2+] = 1.0 x 10-4 M.

16. Williams, spring 2009 stop here

17. Design a voltaic cell with the following half
cells and complete the calculations:
Ag+ (aq) + 1e-  Ag (s) Eo = 0.80 V
Pb2+ (aq) + 2e-  Pb (s) Eo = V
Calculate the Eocell (potential at standard conditions)

18. Design a voltaic cell with the following half
cells and complete the calculations:
Ag+ (aq) + 1e-  Ag (s) Eo = 0.80 V
Pb2+ (aq) + 2e-  Pb (s) Eo = V
Calculate Go.

19. Design a voltaic cell with the following half
cells and complete the calculations:
Ag+ (aq) + 1e-  Ag (s) Eo = 0.80 V
Pb2+ (aq) + 2e-  Pb (s) Eo = V
Calculate 

20. Design a voltaic cell with the following half
cells and complete the calculations:
Ag+ (aq) + 1e-  Ag (s) Eo = 0.80 V
Pb2+ (aq) + 2e-  Pb (s) Eo = V
Calculate the Ecell if [Ag+] = 2.0 M and Pb2+] = 1.0 x 10-4 M.

21. Figure: 18-12
Title:
Cu/Cu2+ Concentration Cell
Caption:
If the two half-cells have the same Cu2+ concentration, the cell potential is zero. If one half-cell has a greater Cu2+ concentration than the other, a spontaneous reaction occurs. In the reaction, Cu2+ ions in the more concentrated cell are reduced (to solid copper), while Cu2+ ions in the more dilute cell are formed (from solid copper). In effect, the concentration of copper ions in the two half-cells tends toward equality.

22. OBJECTIVE 11.4: PROVIDE A THOROUGH OVERVIEW OF APPLICATIONS OF ELECTROCHEMICAL CELLS INCLUDING FUEL CELLS, CORROSION, AND OTHER TOPICS AS TIME PERMITS.

23. CORROSION
corrosion is the spontaneous oxidation of a metal by chemicals in the environment
since many materials we use are active metals, corrosion can be a very big problem

24. RUSTING rust is hydrated iron(III) oxide moisture must be present
electrolytes promote rusting
acids promote rusting
lower pH = lower E°red

25. Dry Cell Batteries Figure: 18-15a,b Title: Dry-Cell Batteries Caption:
(a) In a common dry-cell battery, the zinc case acts as the anode and a graphite rod immersed in a moist, slightly acidic paste of MnO2 and NH4Cl acts as the cathode. (b) The longer-lived alkaline batteries now in common use employ a graphite cathode immersed in a paste of MnO2 and a base.

26. Lead – Acid Storage Battery
Figure: 18-16
Title:
Lead-Acid Storage Battery
Caption:
A lead-acid storage battery consists of six cells wired in series. Each cell contains a porous lead anode and a lead oxide cathode, both immersed in sulfuric acid.

27. Biological Electrochemistry
Figure: 18-13
Title:
Potential Changes Across the Nerve Cell Membrane
Caption:
The changes in ion concentrations that take place when a nerve cell is stimulated result in a spike in the electrochemical potential across the membrane.

28. Lithium Ion Battery Figure: 18-17 Title: Lithium Ion Battery Caption:
In the lithium ion battery, the spontaneous flow of lithium ions from the graphite anode to the lithium transition metal oxide cathode causes a corresponding flow of electrons in the external circuit.

29. Figure: 18-18
Title:
Hydrogen-Oxygen Fuel Cell
Caption:
In this fuel cell, hydrogen and oxygen combine to form water.

30. Figure: 18-19a,b
Title:
Fuel-Cell Breathalyzer
Caption:
The fuel-cell breathalyzer works by oxidizing ethyl alcohol in the breath to acetic acid. The electrical current that is produced is proportional to the concentration of ethyl alcohol in the breath.