Question

a sample of lead weighing 1.05g was dissolved in a small quantity of nitric acid to produce aqueous solution of Pb2+ and Ag+(which is present as impurity).the volume of the solution was increased to 300ml by adding water, a pure silver electrode was immersed in the solution and the potential difference between this electrode and the standered electrode was found to be 0.503V at 25 degree celcius.what was the %of Ag in the lead metal?Given E0 (Ag+/Ag)=0.799v.neglecting amount of Ag+ converted to Ag.