The gas which has similar shape and bond order as that of azide ion is:

Options

A. Sulphur dioxide
B. Ozone
C. Sulphur trioxide
D. Carbon dioxide

Answer

To determine the gas that has a similar shape and bond order as that of the azide ion (N₃⁻), we will follow these steps:

### Step 1: Understand the Structure of Azide Ion
The azide ion (N₃⁻) has a linear structure. It can be represented as:
- N≡N⁻—N⁺ (where the first nitrogen is triple-bonded to the second nitrogen, and the second nitrogen is single-bonded to the third nitrogen).

### Step 2: Determine the Bond Order of Azide Ion
The bond order can be calculated using the formula:
\[ \text{Bond Order} = \frac{\text{Number of bonds}}{\text{Number of resonating structures}} \]

In the case of azide ion, we have:
- Total bonds = 3 (two double bonds and one single bond)
- Total resonating structures = 2

Thus, the bond order of azide ion is:
\[ \text{Bond Order} = \frac{3}{2} = 1.5 \]

### Step 3: Identify the Shape of Azide Ion
As mentioned earlier, the azide ion has a linear shape.

### Step 4: Analyze the Options
Now, we will analyze the provided options to find a gas with a linear shape and a bond order of 1.5.

1. **Sulfur Dioxide (SO₂)**:
- Shape: Bent
- Bond Order: 2 (one double bond with each oxygen)
- **Not a match**.

2. **Ozone (O₃)**:
- Shape: Bent
- Bond Order: 1.5 (due to resonance)
- **Not a match** (shape is not linear).

3. **Sulfur Trioxide (SO₃)**:
- Shape: Trigonal planar
- Bond Order: 2 (three double bonds with oxygen)
- **Not a match**.

4. **Carbon Dioxide (CO₂)**:
- Shape: Linear
- Bond Order: 2 (two double bonds with oxygen)
- **Not a match**.

### Conclusion
None of the options provided have both a linear shape and a bond order of 1.5. However, if we consider the bond order of CO₂ (which is 2) and its linear shape, it is the closest option.

Thus, the answer is **Carbon Dioxide (CO₂)**, as it shares the linear shape with azide ion, even though the bond order is slightly different.