Which one of Na, Cu, Zn, Fe, Mg will not liberate hydrogen gas from hydrochloric acid?

Explanation

To determine which metal will not liberate hydrogen gas from hydrochloric acid (HCl), we need to consider the reactivity of the metals in relation to hydrogen. Here's a step-by-step solution:

### Step 1: Understand the Reaction
When a reactive metal reacts with hydrochloric acid, it displaces hydrogen from the acid, resulting in the liberation of hydrogen gas (H₂). The general reaction can be represented as:
\[ \text{Metal (M)} + \text{HCl} \rightarrow \text{Metal Chloride} + \text{H}_2 \uparrow \]

### Step 2: List the Metals
The metals given in the question are:
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