Final answer:
The chemical reaction between magnesium and hydrochloric acid is a single replacement reaction that produces hydrogen gas and magnesium chloride.
Step-by-step explanation:
The reaction between magnesium and hydrochloric acid is an example of a single replacement reaction. During this chemical reaction, the magnesium displaces the hydrogen in hydrochloric acid forming magnesium chloride and hydrogen gas. The balanced chemical equation is Mg(s) + 2HCl(aq) → MgCl₂(aq) + H₂(g). In addition to hydrogen gas, magnesium chloride, which is a salt, is also produced during this reaction. This reaction is important in various applications, such as manufacturing and in treating stomach acidity with antacids.