Oxidation-Reduction

 

38) The reason for each of the choices below is the same. The more readily a substance is reduced (the more positive the E°red or the more negative the E°ox ) the stronger the oxidizing agent.

 

      (a) Ce4+(aq) + e- Ce3+(aq)                            E°red = +1.61 V

           Br2(l) + 2e- 2Br-(aq)                                 E°red = +1.065 V

           H2O2(aq) + 2H+(aq) + 2e- 2H2O(l)          red = +1.776 V

           Zn(s) + 2e-                                                             E°red = ??? (Zn is not very likely to be reduced.)

 

           H2O2(aq) is the strongest oxidizing agent and Zn(s) is the weakest.

 

      (b) F2(g) + 2e- 2F-(aq)                                                 E°red = +2.87 V

           Zn2+(aq) + 2e- Zn(s)                                               E°red = -0.763 V

           N2(g) + 5H+(aq) + 4e- N2H5+(aq)                          E°red = -0.23 V

           I2(s) + 2e- 2I-(aq)                                                    E°red = +0.536 V

           NO3-(aq) + 4H+(aq) + 3e- NO(g) + 2H2O(l)          E°red = +0.96 V

 

           Zn(s) is the strongest reducing agent and F- is the weakest.