Question

Q1. Which reaction represents the half-reaction of lead (Pb) and the SRP value that could be found on an electric potential table?
Q2.Which value represents the standard cell potential of the spontaneous overall reaction?

Answer 1

The reaction that represents the half-reaction of lead Pb is    
    Pb2+(aq) + 2e- → Pb(s)   
and the SRP value on electric potential table is -0.13V.

To find the overall potential of a reaction, two half reactions can be added
together:
Oxidation:           Fe(s) → Fe2+(aq) + 2e-                               +0.44V
Reduction:          Pb2+(aq) + 2e- → Pb(s)                               - 0.13 V      
Overall reaction: Fe(s) + Pb2+(aq) → Pb(s) + Fe2+(aq)         +0.31V

This positive voltage for the overall reaction is spontaneous.