Final answer:
The reaction Mg(s) + 2HCl(aq) → H₂(g) + MgCl₂(aq) is classified as a displacement reaction, more specifically, a metal replacement reaction because magnesium, a metal, replaces hydrogen in hydrochloric acid. Option d.
Step-by-step explanation:
The reaction given is Mg(s) + 2HCl(aq) → H₂(g) + MgCl₂(aq), which is an example of a displacement reaction, specifically a single-displacement or single-replacement reaction.
In this type of reaction, an element (in this case, magnesium, Mg) reacts with a compound (hydrochloric acid, HCl), and in the process, it displaces another element from the compound (hydrogen, H) to produce a new compound (magnesium chloride, MgCl₂) and a pure element (hydrogen gas, H₂).
There are different types of single-replacement reactions such as metal replacement, hydrogen replacement, and halogen replacement. The reactions are classified based on the type of element that gets displaced. Since magnesium is a metal and it replaces hydrogen, this is a metal replacement reaction. Option d