!!!Half reaction Eo Li++ e- → Li -3.04 Na+ + e- → Na -2.71 Mg+2 + 2e- → Mg -2.38 Al+3 + 3e- → Al -1.66 2H2O + 2e- → H2(g) + 2OH- -0.83 Zn+2 + 2e- → Zn -0.76 Cr+3 + 3e- → Cr -0.74 Fe+2 + 2e- → Fe -0.41 Cd+2 + 2e- → Cd -0.40 Ni+2 + 2e- → Ni -0.23 Sn+2 + 2e- → Sn -0.14 Pb+2 + 2e- → Pb -0.13 Fe+3+3 + 3e- → Fe -0.04 2H+ + e- → H2 0.00 Balance by inspection 1. H2 + O2 → H2O 2. Na + H2O → Na+ + OH- + H2 3. C6H12O6 + O2 → CO2 + H2O Simple redox reactions (use change of oxidation method) 4. Cu + Zn+2 → Zn + Cu+2 5. Al + Fe+3 → Al+3 + Fe+2 6. Pb + Cr+3 → Pb+2 + Cr 7. Li + F2 → Li+ + F- 1. 2. 3. 4. Half reaction Eo Sn+4 + 2e-→ Sn+2 +0.15 Cu+2 + e-→ Cu+ +0.16 Cu+2 + 2e-→ Cu +0.34 I2 + 2e-→ 2I- +0.54 Fe+3 + e- → Fe+2 +0.77 Ag+ + e- → Ag +0.80 Hg+2 + 2e- → Hg +0.85 NO3- + 4H+ + 3e- → NO + 2H2O +0.96 Br2 + 2e- → 2Br- +1.07 O2 + 4H+ + 4e- → 2H2O +1.23 Cr2O7-2 + 14H++ 6e- → 2Cr+3 + 7H2O +1.33 Cl2 + 2e- → 2Cl- +1.36 MnO4-2 + 8H+ + 5e- → Mn+2 + 4H2O +1.49 F2 + 2e- → 2F- +2.87 Acid (use change of oxidation method in acid) 8. Mn+2 + I2→ MnO- + I- 9. BrO3- + N2H4 → Br - + N2 10. Fe+3 + H2O → O2 + Fe+2 11. P4 + NO3- → H2PO4- + NO 12. Cr2O7-2 + Sn+2 → Cr+3 + Sn+4 Base (use change of oxidation method in base) 13. CN- + MnO4- → MnO2 + CNO- 14. Fe(OH)2 + O2 → Fe(OH)3 15. C2H5OH + MnO4- → C2H3O2- + MnO2 5. 6. 7. 8. 15 reactions to use in answering the questions below.!Part I. Balance all of the electrochemical (redox) reactions above. Refer to Worksheet 9 for assistance in how to perform the “change of oxidation method” approach. For those who are more comfortable with the “half reaction method”, feel free to use that. It yields the same result—but it can take more time. CH302 Worksheet 10. Balancing Redox reactions and assigning cell convention. Use the table of standard reduction potentials below as required.!!!9. 10. 11. 12. 2. 4. 5. 6. 7. 8. 10. 12. 13. 14. 15. Part II. Standard Cell Potential. Assuming standard conditions, calculate the standard cell potential for reactions: 2, 4, 5, 6, 7, 8, 10 and 12 for the reaction as written, using the equation: Eocell = Eocathode –Eo anode Part III. Cell convention. For reactions 2, 4, 5, 6, 7, 8, 10 and 12 as written above, find the following for the electrochemical cell assuming the reaction is as written: !Reaction!Voltaic!or!Electr olytic!Half!reaction!at!+!electrode!Half!reaction!at!‐!electro de!2!!!!!!!4!!!!!!!5!!!!!!!6!!!!!!!7!!!!!!!8!!!!!!!10!!!!!!!12!!!!!!!!!! Reaction: 2. 4. 5. 6. 7. 8. 10. 12. Cell Shorthand: Part IV. Cell shorthand notation. No one likes to draw all those beakers and wires in an electrochemical cell (except people who like to draw), so electrochemists have developed shorthand electrochemical notation. Use it to draw the electrochemical cells of reactions 2, 4, 5, 6, 7, 8, 10 and
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