Assertion : Carbocation are planar in nature.
Reason : Carbocations are `sp^(2)` hybridised.

Options

A. If both assertion and reason are correct and reason is correct explanation for assertion.
B. If both assertion and reason are correct but reason is not correct explanation for assertion.
C. If assertion is correct but reason is incorrect.
D. If both assertion and reason are incorrect.

Explanation

To solve the question regarding the assertion and reason about carbocations, we can break it down into the following steps:

### Step-by-Step Solution:

1. **Understanding Carbocations**:
- A carbocation is a positively charged carbon atom that has only six electrons in its valence shell, making it electron-deficient. The simplest example is the methyl carbocation, \( \text{CH}_3^+ \).

2. **Hybridization of Carbocations**:
- In a carbocation, the carbon atom is bonded to three other atoms (in the case of the methyl carbocation, three hydrogen atoms). The hybridization of the carbon atom in this case is determined by the number of sigma bonds it forms.
- Since there are three sigma bonds formed (one with each hydrogen), the hybridization is \( \text{sp}^2 \).

3. **Geometry of Carbocations**:
- The \( \text{sp}^2 \) hybridization leads to a trigonal planar geometry. This means that the three substituents (the atoms bonded to the carbon) are arranged in a plane around the carbon atom, with bond angles of approximately 120 degrees.

4. **Evaluating the Assertion and Reason**:
- The assertion states that "Carbocations are planar in nature." This is true because of the trigonal planar geometry resulting from \( \text{sp}^2 \) hybridization.
- The reason states that "Carbocations are \( \text{sp}^2 \) hybridized." This is also true as we have established from the bonding and hybridization analysis.

5. **Conclusion**:
- Since both the assertion and the reason are true, we conclude that the correct answer is that both statements are true and the reason correctly explains the assertion.

### Final Answer:
Both the assertion and the reason are true. The correct option is (A).

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