Concept:A single displacement reaction between a metal and an acid is feasible if the metal has a negative standard reduction potential (placing it above Hydrogen in the electrochemical series).
Solution:- Zinc (Zn) has a standard reduction potential of \( -0.76 \text{ V} \).
- Because it is "above" Hydrogen (\( 0.00 \text{ V} \)), it acts as a stronger reducing agent.
- Zinc will spontaneously donate electrons to the \( H^+ \) ions in Hydrochloric Acid, dissolving into \( ZnCl_2 \) and liberating \( H_2 \) gas. This makes option C highly feasible.
Why other options are incorrect:Silver (Ag) in option D is a coinage metal situated below Hydrogen (positive reduction potential); it cannot displace Hydrogen from acids. Options A and B are thermodynamically non-spontaneous based on their relative reduction potentials.
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