Pyrrole was electropolymerized to $100nm-$thick polypyrrole film on a platinum electrode in

presence of an electroactive molecule D$.$ During the polymerization, D is doped into the

conducting polymer network with the molar ratio of pyrrole monomeric unit to $D=10$:$1.$ The

electroactive film on the platinum electrode is transferred to $0\mathrm{.}1MHCl$ aqueous solution and

its electrochemistry was studied by cyclic voltammograms as shown in Figure $($a$).$ D is oxidized

to $D^{+}$or $D^{+}$is reduced to $D$ in the polymer film within the potential range shown in the Figure

$($a$).$

$($a$)[10$ points$]$ Calculate concentration of $D$ stored in the polypyrrole film. Discuss the

advantage of immobilizing electroactive species into polymer films by comparing the value

with the solubility of D in water. Scan rate $=100m\frac{V}{sec}.$ Maximum concentration of D soluble

in water

$($b$)[10$ points$]$ Calculate theoretical faradaic capacity of polypyrrole film doped with $D$ in

mAh$\frac{r}{g}.$ Compare the value with that of