If I add hydrochloric acid (HCl(aq)) to metallic magnesium (Mg(s)), bubbles of hydrogen gas (H2(g)) are given off and the remaining solution contains chloride ions and magnesium ions (MgCl2(aq)):
Mg(s) + 2HCl(aq) → H2(g) + MgCl2(aq)But if I try to bubble hydrogen gas through an aqueous solution of magnesium chloride, nothing happens. No solid magnesium forms! Why?
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