Extra pure `N_2` can be obtained by heating

Options

A. `NH_3 with CuO`
B. `NH_4 NO_3`
C. `(NH_4)_2 Cr_2 O_7`
D. `Ba(N_3)_2`

Explanation

To obtain extra pure nitrogen gas (N₂), we can heat barium azide (Ba(N₃)₂). Here’s a step-by-step breakdown of the process:

### Step 1: Identify the Compound
We need to identify which compound can be heated to produce pure nitrogen gas. In this case, we consider barium azide.

### Step 2: Heating Barium Azide
When barium azide is heated, it decomposes. The chemical reaction for this process can be represented as follows:

\[ \text{Ba(N}_3\text{)}_2 \rightarrow \text{Ba} + \text{3N}_2 \]

### Step 3: Products of the Reaction
The products of this decomposition reaction are solid barium (Ba) and nitrogen gas (N₂). The nitrogen gas produced is in a pure form because it is generated directly from the decomposition of barium azide.

### Step 4: Purity of Nitrogen
The nitrogen produced is considered pure because:
- Barium azide can be synthesized in a pure form.
- The decomposition yields solid barium as a by-product, which does not interfere with the nitrogen gas produced.

### Conclusion
Thus, the extra pure nitrogen gas can be obtained by heating barium azide (option D).

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