Which gas is liberated when `CaC_(2)` is hydrolysed?

Options

A. `CH_(4)`
B. `C_(2)H_(6)`
C. `C_(2)H_(4)`
D. `C_(2)H_(2)`

Answer

To determine which gas is liberated when calcium carbide (CaC₂) is hydrolyzed, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Hydrolysis Reaction**:
The hydrolysis of calcium carbide involves its reaction with water (H₂O). The chemical equation for this reaction can be written as:
\[ \text{CaC}_2 + 2 \text{H}_2\text{O} \rightarrow \text{Ca(OH)}_2 + \text{C}_2\text{H}_2 \]

2. **Identify the Products**:
From the reaction, we can see that the products formed are calcium hydroxide (Ca(OH)₂) and acetylene (C₂H₂).

3. **Identify the Gas**:
Among the products, C₂H₂ is a gas at room temperature. Therefore, the gas liberated during the hydrolysis of calcium carbide is acetylene.

4. **Check the Options**:
If we are given options such as:
- (1) Methane (CH₄)
- (2) Ethane (C₂H₆)
- (3) Ethene (C₂H₄)
- (4) Acetylene (C₂H₂)

We can see that the correct answer is option (4) Acetylene (C₂H₂).

### Final Answer:
The gas liberated when calcium carbide (CaC₂) is hydrolyzed is **Acetylene (C₂H₂)**.

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