Which metal can not obtained by electrolysis of their aqueous salt solution? — Metallurgy and Isolation of Elements Chemistry Question

💡 Solution & Explanation

Step 1: The feasibility of reducing a metal ion from its aqueous solution depends on its standard reduction potential relative to water. Step 2: Highly reactive, electropositive metals like Magnesium (Mg2+ / Mg = -2.37 V) have reduction potentials much more negative than the reduction of water. Step 3: During the electrolysis of their aqueous solutions, water is preferentially reduced at the cathode to produce hydrogen gas, preventing the deposition of magnesium metal. Thus, magnesium cannot be obtained by electrolyzing its aqueous salt solution (option b).