Concept:Reduction potential indicates how eagerly an ion wishes to gain electrons to return to its neutral metallic state.
Solution:- According to the electrochemical series, reduction potential generally increases (becomes less negative/more positive) as you move "down" the series towards less reactive metals.
- Alkali and heavier alkaline earth metals (Barium, Calcium, Magnesium) are extremely reactive; they desperately want to stay as ions. Thus, they have highly negative reduction potentials.
- Aluminum (Al) is less reactive than Group 2 elements. Its standard reduction potential (\( -1.66 \text{ V} \)) is algebraically greater (less negative) than Magnesium (\( -2.37 \text{ V} \)), Calcium (\( -2.87 \text{ V} \)), and Barium (\( -2.90 \text{ V} \)).
Why other options are incorrect:Barium, Calcium, and Magnesium are all more electropositive than Aluminum, meaning their ionic forms are much harder to reduce.
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