According to Faraday's first law of electrolysis, the mass deposited is proportional to the quantity of electricity.

• Cathode Reaction: $C{u}^{2+}+2e^{-}\to Cu(s)$
• Electricity Required: To deposit $1$ mole ($63.5\text{ g}$) of $Cu$, $2$ moles of electrons ($2\text{ Faradays}$) are required.
• Relationship: $2\text{ F}\to 63.5\text{ g }Cu$
• For $0.5\text{ F}$: $mass=\frac{63.5}{2}\times 0.5=15.875\text{ g}\approx 15.9\text{ g}$.