Consider the following sequence of reaction:
`Na+NH_(3)(g) to [X]overset(N_(2)O)to[Y] overset(Heat)tounderset("Gas pure")([Z])`
Identify [Z] gas:

Options

A. `N_(2)`
B. `NH_(3)`
C. `O_(2)`
D. `H_(2)`

Explanation

To solve the problem, we will analyze the sequence of reactions step by step.

### Step 1: Reaction of Sodium with Ammonia
When sodium (Na) reacts with ammonia (NH₃), it forms sodium amide (NaNH₂).

**Reaction:**
\[ \text{Na} + \text{NH}_3 \rightarrow \text{NaNH}_2 \]
- **Product [X]:** Sodium amide (NaNH₂)

### Step 2: Heating Sodium Amide with Nitrous Oxide
Next, sodium amide (NaNH₂) is heated in the presence of nitrous oxide (N₂O). This reaction leads to the formation of sodium azide (NaN₃) and water (H₂O) is released as a by-product.

**Reaction:**
\[ \text{NaNH}_2 + \text{N}_2\text{O} \rightarrow \text{NaN}_3 + \text{H}_2\text{O} \]
- **Product [Y]:** Sodium azide (NaN₃)

### Step 3: Heating Sodium Azide
Finally, when sodium azide (NaN₃) is heated, it decomposes to produce nitrogen gas (N₂) and sodium (Na).

**Reaction:**
\[ 2\text{NaN}_3 \xrightarrow{\text{Heat}} 3\text{N}_2 + 2\text{Na} \]
- **Product [Z]:** Nitrogen gas (N₂)

### Conclusion
Thus, the gas [Z] that is produced after the complete sequence of reactions is nitrogen gas (N₂).

### Final Answer
**[Z] gas is nitrogen (N₂).**

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