JAMB Physics 2011 Paper

Concept:In electroplating, the metal that supplies the coating is made the anode, while the object to be plated is made the cathode.Explanation:Here, metal $Y$ is used to coat metal $X$, so $Y$ must be connected as the anode.At the anode, $Y$ dissolves into the electrolyte to produce $Y^{n+}$ ions.Metal $X$ must be the cathode because it is the object receiving the plated layer.At the cathode, reduction occurs:$$Y^{n+} + ne^- \rightarrow Y$$This deposits solid metal $Y$ onto the surface of $X$.Very high current is not required for normal electroplating; undesirable deposits may form if it is too high.Therefore, the correct cell arrangement is $Y$ as anode and $X$ as cathode.Answer:None of the given options is correct as written. The correct arrangement is: $Y$ is the anode and $X$ is the cathode.