1. Balance Redox Rxns: Fe(OH) 3 + [Cr(OH) 4 ] -1 Fe(OH) 2 + CrO 4 -2 in base

2. AP CHM HW Read: Chapter 18

3. Review the Multiple-Choice Section of the Midterm.

4. Electro- chemistry

5. Metallic Conduction The flow of electrons through a metal

6. Ionic Conduction The movement of ions (electrolytes) through a solution Electrolytic Conduct.

7. Electrode The surface or point in which oxidation or reduction takes place

8. Anode The electrode where oxidation takes place An Ox (-)

9. Cathode The electrode where reduction takes place Red Cat (+)

10. Voltaic or Galvanic Cell Electrochemical Cell in which:

11. a spontaneous oxidation-reduction reaction produces electrical energy

12. Half-Cell A cell where only oxidation or only reduction takes place

13. An electrochemical cell must have two half-cells connected by a salt bridge

14. A half-cell will not work by itself Both half-cells are required

15. Salt Bridge 1) Allows electrical contact between the two half-cells

16. 2) Prevents mixing of the two half- cell solutions

17. 3) Allows ions to flow maintaining electrical neutrality

18. Determining the Redox Rxn & Voltage of an Electrochemical Cell

19. Identify all molecules & ions (reactants) that exist in the electrolytic cell

20. 1) Determine all possible half- reactions that could occur in the system

21. 2 ) Look up each half-rxn from the Std. Redox Tables

22. 3) Record each half-rxn & its standard voltage

23. 4) Save the oxidation half- rxn that has the highest voltage

24. 5) Save the reduction half- rxn that has the highest voltage

25. 6) Balance the electrons between the two half-rxns

26. 7) Add the two half-rxns to obtain the full electrochemical reaction

27. 7) Add the voltage of each half-rxn to obtain the std. voltage required

28. Determine E o Zn (s) + 2 Ag +1 (aq) 2 Ag (s) + Zn +2 (aq)

29. AP CHM HW Read: Chapter 18 Problems: 7 & 15a Page: 526

30. REDOX Shorthand Zn|Zn +2 ||Ag +1 |Ag ox red Zn||Zn|Zn +2 ||Ag +1 |Ag||Pt an ox red cat

31. Drill: Determine Shorthand Rxn & voltage when Cu +1 is reacts with solid potassium

32. Voltaic Cell Problems

33. Determine all when a cell with a Cu electrode in CuCl 2(aq) is connected to a cell with a Zn electrode in ZnBr 2(aq)

34. Determine all when a cell with a Fe electrode in FeCl 3(aq) is connected to a cell with a Mn electrode in MnCl 2(aq)

35. Determine all when a cell with a Mg electrode in Mg(NO 3 ) 2(aq) is connected to a cell with a Au electrode in Au(NO 3 ) 3 (aq)

36. Drill: What is the best reducing agent on the chart?

37. Electrolysis Using electricity to force an oh fooey non-spontaneous electrochemical rxn

38. Electrolytic Cell Chemical cell where electrolysis is being performed

39. How to determine the Redox Rxn & voltage of an Electrolytic Cell

40. Identify all molecules & ions (reactants) that exist in the electrolytic cell

41. 1) Determine all possible half- reactions that could occur in the system

42. 2 ) Look up each half-rxn from the Std. Redox Tables

43. 3) Record each half-rxn & its standard voltage

44. 4) Save the oxidation half- rxn that has the highest voltage

45. 5) Save the reduction half- rxn that has the highest voltage

46. 6) Balance the electrons between the two half-rxns

47. 7) Add the two half-rxns to obtain the full electrochemical reaction

48. 7) Add the voltage of each half-rxn to obtain the std. voltage required

49. Determine the rxn that takes place when 1.5 V is passed through two Pt electrodes in a solution containing MgI 2(aq) & ZnCl 2(aq)

50. AP CHM HW Read: Chapter 18 Problems: 23 & 24 Page: 526

51. Determine the rxn that takes place when 2.5 V is passed through two Pt electrode in a solution of NaCl (aq)

52. Determine the rxn that takes place when electricity is passed through two Pt electrode in molten NaCl

53. Drill: Determine the rxn that takes place when electricity is passed through two Pt electrodes in ZnCl 2(aq)

54. A car battery has lead & lead(IV)oxide electrodes in an acidified aqueous lead(II)sulfate solution. Using the book, determine the voltage that can be produced.

55. Relating Equations  G o =  H o - T  S o  G o = -RTlnK eq  G o = -nF E o

56. Determine rxn, E o,  G o, & K eq for a voltaic cell with half- cells containing Ni (s) in NiCl 2(aq) & Sn (s) in SnCl 2(aq).

57. Nernst Equation E = E o - (RT/nF)lnQ for non-standard conditions

58. Determine the voltage of a cell with a silver electrode in 1.0 M AgNO 3 & an iron electrode in 0.10 M Fe(NO 3 ) 2 at 27 o C

59. Drill: Determine the rxns that take place when 9.65 mA is passed for 2.5 Hrs through two Pt electrodes in a solution containing MnBr 2(aq) & CuF 2(aq)

60. AP CHM HW Read: Chapter 18 Problems: 41 Page: 528

61. The test on electrochemistry will be on Thursday.

62. Determine the voltage of a cell with a silver electrode in 1.0 M AgNO 3 & a zinc electrode in 0.010 M Zn(NO 3 ) 2 at 27 o C

63. Determine the voltage of a cell with a copper electrode in 0.10 M CuNO 3 & a zinc electrode in 1.0 M Zn(NO 3 ) 2 at 27 o C

64. Determine the voltage of a cell with a silver electrode in 0.10 M AgNO 3 & a zinc electrode in 1.0 M Zn(NO 3 ) 2 at 27 o C

65. Electroplating & Electro-purifying

66. Electrolysis During electrolysis, oxidation & degradation would occur at the anode while reduction & electroplating would occur at the cathode

67. Current Formula Current = charge/unit time Amps = coul/sec Amount (mass, volume, moles, etc) can be determined from the charge

68. Calculate the mass of copper plated onto the cathode when a 9.65 mAmp current is applied to a solution of CuSO 4 for 5.0 minutes.

69. Calculate the years required to plate 216 kg onto the cathode when a 96.5 mAmp current is applied to a solution of AgNO 3

70. Drill: Calculate the current required to purify 510 kg of aluminum oxide in 5.0 hours

71. Test Monday

72. Calculate the time required to electroplate 19.7 mg of gold onto a plate by passing 965 mA current through a solution of Au(NO 3 ) 3

73. Calculate the time required to gold plate a 2.0 mm layer onto a 250 cm 2 plate by passing 965 mA current through a solution of Au(NO 3 ) 3 (D Au = 20 g/cm 3 )

74. Calculate the time required to purify a 204 kg of ore that is 60.0 % Al 2 O 3 by applying a 965 kA current through molten ore sample:

75. Calculate the time required to purify a 32 kg of ore that is 75.0 % Fe 2 O 3 by applying a 9.65 kA current through molten ore sample:

76. Determine the voltage of a cell with a silver electrode in 5.0 M AgNO 3 & an zinc electrode in 0.25 M Zn(NO 3 ) 2 at 27 o C

77. Drill: A voltaic cell with a silver electrode in 0.10 M Ag + & a zinc electrode in 1.0 M Zn +2 at 27 o C is allowed to react for 5.0 mins at 9.65 A. Calculate: E o, E,  G o, & mass increase of the cathode.

78. Determine the rxn that takes place when 1.0 V is passed through two Pt electrodes in a 2.0 L soln containing 1.0 M NaI (aq) & 1.0 M CoCl 2(aq). Using 95.5 mA, determine rxn time.