Which of the following metals can be used for liberating hydrogen from dilute hydrochloric acid ?
(i) Zinc (ii) Copper (iii)Iron (iv) Silver (v) Magnesium

Explanation

To determine which metals can liberate hydrogen from dilute hydrochloric acid (HCl), we will refer to the activity series of metals. The activity series ranks metals based on their ability to displace hydrogen from acids.

### Step-by-Step Solution:

1. **Understand the Activity Series**:
- The activity series is a list of metals arranged in order of decreasing reactivity. Metals that are higher in the series can displace metals that are lower in the series from their compounds.
- Hydrogen is included in this series, and metals above hydrogen can displace it from acids.

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