Question

A chemist adds a strip of magnesium metal to an acidic solution. Which of the following best describes the reaction that would occur when the magnesium metal is added to the acidic solution?

A. Magnesium metal reacts with acids to produce magnesium oxide and water.
B. Magnesium metal undergoes oxidation to form magnesium ions.
C. Magnesium metal displaces hydrogen ions in the acid to produce hydrogen gas.
D. Magnesium metal dissolves in the acid to form a soluble magnesium compound.

Answer 1

The best description of the reaction when magnesium metal is added to an acidic solution is option C, where magnesium displaces hydrogen ions to produce hydrogen gas and forms a magnesium salt in solution. The correct option is c.

Step-by-step explanation:

When magnesium metal is added to an acidic solution, hydrogen gas is produced along with a magnesium salt. Therefore, the correct answer is C. Magnesium metal displaces hydrogen ions in the acid to produce hydrogen gas.

This process is categorized as a single-replacement reaction where the magnesium (Mg) reacts with the acid to form magnesium ions (Mg2+) in the solution and releases hydrogen gas (H2). For example:

Mg(s) + 2HCl(aq) → MgCl2(aq) + H2(g)

In this equation, magnesium replaces hydrogen in hydrochloric acid, resulting in magnesium chloride and hydrogen gas. The magnesium undergoes oxidation during this process. The correct option is c.