JAMB Chemistry 2024 Paper

Concept:Electrolysis uses Faraday’s law: one faraday deposits one mole of electrons, but copper needs two moles of electrons per mole deposited.Explanation:Copper(II) tetraoxosulphate(VI) contains $\mathrm{Cu}^{2+}$ ions.The cathode reaction is:$$\mathrm{Cu}^{2+} + 2e^- \rightarrow \mathrm{Cu}$$So $1$ mole of copper requires $2$ moles of electrons.Since $1$ faraday $= 1$ mole of electrons, $2$ faradays provide $2$ moles of electrons.Therefore, $2$ faradays will deposit exactly $1$ mole of copper.Answer:B. $1.0$ mole