# Calculate the standard cell potential for each of the following.

Submitted by moe6142 on Thu, 03/22/2012 - 21:46

Calculate the standard cell potential for each of the following.
a) H2(G) + F2(g) ----> 2H+ (aq) +2F-(aq)
b) Cu(s) +Ba2+ (aq) ---> Cu2+ (aq) + Ba(s)

c) 3Fe 2+(aq) ---> Fe(s) + 2Fe 3+ (aq)

d)  Hg2 2+(aq) + 2Cu+ (aq) ---> 2Hg(l) + 2 CU 2+(aq)

Separate the half reactions, look up the standard reduction potential and calculate potential different

eg if the cells are standard and you have the reaction 2Ni2+ + Mg ---> Mg2+ + Ni. The half reactions are

Mg---> Mg2+ + 2e- (has -Eo of +2.37V = this is a -Eo as it has been reversed compared to the reaction in the standard reduction potential series ) and Ni2+ + 2e- ---> Ni (Eo of -0.23V. So the cell potential would be 2.37 + -0.23 = 2.14V. The values are added because the two equations are added to get the overall reaction

Mg---> Mg2+ + 2e- s -Eo =2.37V

Ni2+ + 2e- ---> Ni Eo =-0.23V

Mg + Ni2+ ---> Mg2+ + Ni  Cell potential = 2.37 + (-0.23) = +2.14V