The given reactions such as
I.`Zn+2HClrarrZnCl_2+H_2`
II.`Fe+2HClrarrFeCl_2+H_2` are represented as

Options

A. displacement of zinc and iron metals
B. displacement of only zinc metal
C. displacement of only iron metal
D. displacement of hydrogen only

Answer

To solve the question regarding the given reactions, we will analyze the reactions step by step.

### Step-by-Step Solution:

1. **Identify the Reactions**:
- The first reaction is:
\[ \text{Zn} + 2\text{HCl} \rightarrow \text{ZnCl}_2 + \text{H}_2 \]
- The second reaction is:
\[ \text{Fe} + 2\text{HCl} \rightarrow \text{FeCl}_2 + \text{H}_2 \]

2. **Determine the Type of Reaction**:
- Both reactions involve a metal (Zn or Fe) reacting with an acid (HCl) to produce a salt (ZnCl₂ or FeCl₂) and hydrogen gas (H₂).
- This indicates that these reactions are examples of **single displacement reactions** (also known as single replacement reactions), where a more reactive metal displaces hydrogen from the acid.

3. **Refer to the Reactivity Series**:
- The reactivity series ranks metals based on their ability to displace other metals from compounds. In this case, both zinc and iron are more reactive than hydrogen.
- Therefore, zinc can displace hydrogen from hydrochloric acid, and iron can also do the same.

4. **Conclusion**:
- Since both reactions involve the displacement of hydrogen by a metal, we can conclude that these reactions represent **displacement reactions**.

### Final Answer:
Both reactions represent **displacement reactions** where metals displace hydrogen from hydrochloric acid.

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