Concept:A single displacement redox reaction occurs when a more reactive solid metal is placed into a solution containing ions of a less reactive metal.
Solution:- Look at the electrochemical series. Iron (Fe) has a reduction potential of \( -0.44 \text{ V} \), while Copper (Cu) has a reduction potential of \( +0.34 \text{ V} \).
- Because Iron is higher in the reactivity series (it is a stronger reducing agent), it wants to lose its electrons to the Copper ions.
- The Iron rod will begin to dissolve (oxidize) into \( Fe^{+2} \) ions: \( Fe \rightarrow Fe^{+2} + 2e^- \).
- The \( Cu^{+2} \) ions in the blue sulfate solution will accept those electrons and reduce into solid Copper metal: \( Cu^{+2} + 2e^- \rightarrow Cu \).
- This solid Copper will be deposited on the iron rod and at the bottom of the beaker.
Why other options are incorrect:Iron does not precipitate; it actively dissolves. Copper does not dissolve; it precipitates out of solution. The reaction is highly spontaneous, so "no reaction" is false.
Quality & Fidelity Assurance:
Every question on BeambePrep is rigorously curated against the official PMDC syllabus with zero filler, zero out-of-syllabus content, and zero typos. When an authentic past paper originally contained a historical mistake or ambiguity from the examining board (such as UHS or NUMS), BeambePrep faithfully reflects the original paper while detailing the nuance and scientific consensus in the autopsy above.