Which metal can be used to remove magnesium ions (Mg2+) from solution? Which metal can be used to remove magnesium ions (Mg2+) from solution? Al (s) K (s) Zn (s) None of these
The Correct Answer and Explanation is:
The correct answer is Al (s) (Aluminum).
Explanation:
The removal of magnesium ions (Mg²⁺) from solution typically involves a redox reaction where a metal displaces magnesium from its ionic form. In a displacement reaction, a metal with a more negative reduction potential can reduce the magnesium ions (Mg²⁺) to magnesium metal (Mg), while the metal itself gets oxidized.
Magnesium (Mg) has a standard reduction potential of -2.37 V, meaning it readily loses electrons and forms ions in solution. For a metal to displace Mg²⁺ ions from solution, its reduction potential must be more negative than that of magnesium.
- Aluminum (Al) has a more negative reduction potential of -1.66 V, meaning it can easily lose electrons and oxidize to Al³⁺ while reducing Mg²⁺ ions to solid magnesium metal (Mg). Hence, aluminum can remove magnesium ions from solution via this redox process.
- Potassium (K), with a reduction potential of -2.93 V, is also more negative than magnesium. However, potassium is highly reactive and would react explosively with water, making it impractical for such a reaction in aqueous solutions.
- Zinc (Zn) has a reduction potential of -0.76 V, which is more positive than that of magnesium, so zinc would not be able to reduce Mg²⁺ ions from solution.
Therefore, aluminum (Al) is the metal that can effectively remove magnesium ions from solution in this context.
