Assertion : Butane and 2-methylbutane are homologues.
Reason : Butane is a straight chain alkene while 2-methylbutane is a branched chain alkene.

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, we will analyze both the assertion and the reason provided.

### Step 1: Analyze the Assertion
The assertion states that "Butane and 2-methylbutane are homologues."

- **Definition of Homologues**: Homologues are compounds that differ by a repeating unit, typically a -CH2- group, and have the same functional group and similar chemical properties.
- **Structures**:
- Butane (C4H10): CH3-CH2-CH2-CH3
- 2-Methylbutane (C5H12): CH3-CH(CH3)-CH2-CH3

Since 2-methylbutane can be derived from butane by adding a -CH2- group, they are indeed homologues.

### Conclusion for Assertion:
The assertion is **True**.

### Step 2: Analyze the Reason
The reason states that "Butane is a straight chain alkene while 2-methylbutane is a branched chain alkene."

- **Identifying the Type of Compounds**:
- Butane is an alkane (single bonds only) and not an alkene (which contains at least one double bond).
- 2-Methylbutane is also an alkane, not an alkene.

### Conclusion for Reason:
The reason is **False** because both butane and 2-methylbutane are alkanes, not alkenes.

### Final Conclusion:
- The assertion is **True**.
- The reason is **False**.

Thus, the correct answer is that the assertion is true, but the reason is false.

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