Identify the incorrect statement related to `PCl_(5)` from the following

Options

A. `PCl_(5)` molecule in non-reactive.
B. Three equatorial P-Cl bonds make an angle of `120^(@)` with each other
C. Two axial P-Cl bonds make an angle of `180^(@)` with each other
D. Axial P-Cl bonds are longer than the equatorial P-Cl bonds.

Explanation

To identify the incorrect statement related to \( PCl_5 \), we will analyze each statement provided in the question based on the properties and structure of \( PCl_5 \).

### Step-by-Step Solution:

1. **Understanding the Hybridization of \( PCl_5 \)**:
- The central atom in \( PCl_5 \) is phosphorus (P), which has 5 valence electrons.
- There are 5 chlorine (Cl) atoms surrounding the phosphorus atom.
- The hybridization can be calculated using the formula:
\[ \text{Hybridization} = \frac{1}{2} \left( \text{Valence electrons of central atom} + \text{Number of monovalent atoms} \right) \]
Here, it becomes:
\[ \text{Hybridization} = \frac{1}{2} \left( 5 + 5 \right) = 5 \quad \text{(which corresponds to } sp^3d\text{)} \]

2. **Determining the Geometry of \( PCl_5 \)**:
- The geometry of \( PCl_5 \) is trigonal bipyramidal due to the \( sp^3d \) hybridization.
- In this geometry, there are three equatorial Cl atoms and two axial Cl atoms.

3. **Analyzing Each Statement**:
- **Statement 1**: \( PCl_5 \) molecule is non-reactive.
- This statement is incorrect. \( PCl_5 \) is actually reactive due to the presence of two weak axial bonds.
- **Statement 2**: Three equatorial Cl bonds make an angle of 120 degrees with each other.
- This statement is correct. In a trigonal bipyramidal structure, the equatorial bonds are indeed at 120 degrees.
- **Statement 3**: Two axial \( PCl \) bonds make an angle of 180 degrees with each other.
- This statement is correct. The axial bonds are aligned opposite to each other, making a 180-degree angle.
- **Statement 4**: Axial \( PCl \) bonds are longer than equatorial \( PCl \) bonds.
- This statement is also correct. Due to the steric hindrance and bond angles, axial bonds are longer.

4. **Conclusion**:
- The only incorrect statement is **Statement 1**, which claims that \( PCl_5 \) is non-reactive. In reality, \( PCl_5 \) is highly reactive due to the weak axial bonds.

### Final Answer:
The incorrect statement related to \( PCl_5 \) is: **"PCl_5 molecule is non-reactive."**