Chapter 17
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OIL - Oxyidation is ( loss of electrons)
RIG - Reduction is (gain of electrons)

The best oxyidizing agent = the one most easily reduced (most postive)
Best reducing agent= the one most easily oxydized (most negative)

Electrochemical cells- produce or use electricity
     
voltaic cells- are spontaneous
     
electrolytic cells- are non spontaneous

First battery- Volta

Anode
- negative- site of OIL
Cathode- postive- site of RIG

The ability to move electrons through a wire is called
potential- measured in volts

In
electroplating the object being plated is the cathode
               Calculate E at 25 C for the cell.

                Ag+ + e- --> Ag (s)   + .8 volts
              Ni 2+ + 2e- --> Ni (s)    -.23 volts

                    
E= E* - .0592/n   Log Q

                     2Ag+ +2e- --> 2 Ag (s)  .8V
                   +Ni (s) --> Ni 2+ + 2e-    .23V
                    ------------------------------------
                  2Ag+ + Ni (s) --> 2Ag (s) + Ni 2+
                              
1.03 V = E*

E= 1.03 - (.0592 / 2) log ([Ni2+] / [Ag+]^2)
E= 1.03- (.0592 / 2) log (1x10^-3  /  (1.6x10^-10)^2
                            
E= .5388 volts
Example:
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