This section contains Assertion and Reason type question each question has 4 choices (1)(2)(3)(4) out of which only one is correct
Assertion(A):`PCl_5` molecules has trigonal bipyramidal structure
Reason(R):The hybridisation of `PCl_5` is `sp_3d`

Options

A. Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation of Assertion
C. Assertion is correct but Reason is incorrect
D. Both Assertion and Reason are incorrect

Answer

To solve the assertion and reason question regarding the structure and hybridization of \( PCl_5 \), we will analyze both the assertion and the reason step by step.

### Step 1: Analyze the Assertion
**Assertion (A):** \( PCl_5 \) molecules have a trigonal bipyramidal structure.

- **Explanation:** The molecular geometry of \( PCl_5 \) can be determined by considering the arrangement of its atoms. Phosphorus (P) is the central atom surrounded by five chlorine (Cl) atoms. In \( PCl_5 \), there are five bonding pairs of electrons and no lone pairs. This arrangement leads to a trigonal bipyramidal geometry, where three chlorine atoms occupy the equatorial positions and two chlorine atoms occupy the axial positions.

### Step 2: Analyze the Reason
**Reason (R):** The hybridization of \( PCl_5 \) is \( sp^3d \).

- **Explanation:** To determine the hybridization, we look at the number of sigma bonds and lone pairs around the central atom (phosphorus). In \( PCl_5 \), there are five sigma bonds formed between phosphorus and chlorine atoms. The hybridization that accommodates five regions of electron density (five sigma bonds) is \( sp^3d \). This hybridization corresponds to the trigonal bipyramidal geometry as well.

### Step 3: Conclusion
- Both the assertion and the reason are correct. The reason provides a correct explanation for the assertion.

### Final Answer
The correct choice is: **(1) Both assertion and reason are correct, and the reason is the correct explanation of the assertion.**

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