1 / 104

Balance Redox Rxns:

Balance Redox Rxns:. Fe(OH) 3 + [Cr(OH) 4 ] -1 Fe(OH) 2 + CrO 4 -2. Electro-chemistry. Metallic Conduction. The flow of electrons through a metal. Ionic Conduction. The movement of ions (electrolytes) through a solution Electrolytic Conduct. Electrode.

akeem-andrews
Télécharger la présentation

Balance Redox Rxns:

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Balance Redox Rxns: • Fe(OH)3 + • [Cr(OH)4]-1 • Fe(OH)2 + CrO4-2

  2. Electro-chemistry

  3. Metallic Conduction • The flow of electrons through a metal

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

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

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

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

  8. Voltaic or Galvanic Cell • Electrochemical Cell in which:

  9. a spontaneous oxidation-reduction reaction produces electrical energy

  10. Voltaic or Galvanic Cell • Batteries are made up of VCs

  11. Half-Cell • A cell where either oxidation or reduction takes place

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

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

  14. Salt Bridge • ) Allows electrical contact between the two half-cells

  15. ) Prevents mixing of the two half-cell solutions

  16. ) Allows ions to flow maintaining electrical neutrality

  17. Draw a Voltaic Cell made up of two half-cells

  18. Drill: Define Each • Oxidation • Reduction • Anode • Cathode

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

  20. 1) List all species (molecules, elements, & ions) (reactants) that exist in each cell

  21. 2a) From the Redox Tables write all possible half-reactions that could occur in the system

  22. b ) Record the voltage for each half-rxn. If rxn is reversed, change sign.

  23. 3) Label the oxidation half-rxn that has the highest voltage

  24. 4) Label the reduction half-rxn that has the highest voltage

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

  26. 6a) Add the two half-rxns to obtain the full electrochemical reaction

  27. 6b) Add the voltage of each half-rxn to obtain the std. voltage required

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

  29. REDOX Shorthand • Zn|Zn+2||Ag+1|Ag ox red • Zn||Zn|Zn+2||Ag+1|Ag||Ag an ox red cat

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

  31. Voltaic Cell Problems

  32. Determine all when a cell with a Cu electrode in CuCl2(aq) is connected to a cell with a Zn electrode in ZnBr2(aq)

  33. Drill: Determine all species that could react when a cell with an Fe electrode in FeCl3(aq) is connected to a cell with a Mn electrode in MnCl2(aq)

  34. Determine all when a cell with a Fe electrode in FeCl3(aq) is connected to a cell with a Mn electrode in MnCl2(aq)

  35. Drill: Determine all species that could react when a cell with an Fe electrode in FeCl2(aq) is connected to a cell with a Mg electrode in MgCl2(aq)

  36. Determine all when a cell with a Mg electrode in MgCl2(aq) is connected to a cell with a Au electrode in AuCl3(aq)

  37. Determine all when a cell with a Cd electrode in CdCl2(aq) is connected to a cell with a Cu electrode in CuI(aq)

  38. What could happen if you dissolve AuCl3 in water?

  39. Drill: A voltaic cell is made up of a iron electrode in an aqueous of FeI2 in one chamber & a copper electrode in an aqueous CuBr2. Determine all of the substances that could be reactants in this system.

  40. A voltaic cell is made up of a iron electrode in an aqueous of FeI2 in one chamber & a copper electrode in an aqueous CuBr2. Determine all in this system.

  41. Drill: Determine all species that could react when a cell with an Cr electrode in CrBr3(aq) is connected to a cell with a Sn electrode in SnI2(aq)

  42. Determine all when a cell with an chromium electrode in CrBr3(aq) is connected to a cell with a tin electrode in SnI2(aq)

  43. Using the standard Reduction Potential Table, determine the element that is the strongest reducing agent, & the one that ic the strongest oxidizing agent.

  44. Balance Redox Rxn: • SnO2 + S8 • SnO + SO2 • in acid

  45. Balance Redox Rxn: • N2O3 + K2CrO4 • KNO3 + Cr+3 • in base

  46. Balance Redox Rxn: • SO + H2Cr2O7 • H2SO4 + Cr+2

  47. Drill: What is the best reducing agent and the best oxidizing agent on the chart?

  48. Extremely Important Electrochemical Reactions

  49. Lead Sulfate Battery Pb + SO4-2  PbSO4 + 2e-Eo = 1.7 V PbO2 + 4H+ + 2e- PbSO4 + H2O Eo = 0.3 V Pb + PbO2 + 4H+ SO4-2  2 PbSO4 + H2O Eo = 2.0 V

  50. Iron Rusting 2Fe  2Fe+2 + 4e- O2 + 2H2O + 4e- 4OH- 2Fe + O2 + 2H2O  2Fe+2 + 4OH-

More Related