Assertion : 2-Butanol on heating with `H_2SO_4` gives 1-butene and
2-butene
Reason: Dehydration of 2 - butanol follows Saytzeff's rule.

Options

A. if both assertion and reason are true and reason is thr correct explanation of assertion
B. If both assertion and reason are true but reason is not the correct explanation of assertion
C. If assertion is true but reason is false
D. If both assertion and reson are false.

Explanation

To solve the question, we need to analyze the assertion and the reason provided.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that 2-butanol on heating with sulfuric acid (H₂SO₄) produces 1-butene and 2-butene.
- This is a dehydration reaction where an alcohol loses a water molecule to form an alkene.

2. **Dehydration of 2-Butanol**:
- The structure of 2-butanol is CH₃-CH(OH)-CH₂-CH₃.
- When heated with H₂SO₄, the hydroxyl group (OH) is removed along with a hydrogen atom from a neighboring carbon (beta carbon), resulting in the formation of alkenes.

3. **Applying Saytzeff's Rule**:
- Saytzeff's rule states that in elimination reactions, the more substituted alkene (the one with more alkyl groups attached to the double bond) will be the major product.
- In the case of 2-butanol, the dehydration can lead to two possible products:
- 1-butene (less substituted, minor product)
- 2-butene (more substituted, major product)

4. **Products Formation**:
- The dehydration of 2-butanol can yield:
- Major product: 2-butene (CH₃-CH=CH-CH₃)
- Minor product: 1-butene (CH₂=CH-CH₂-CH₃)
- Therefore, the assertion is correct.

5. **Analyzing the Reason**:
- The reason states that the dehydration of 2-butanol follows Saytzeff's rule, which is indeed true as the formation of the more substituted alkene (2-butene) is favored.

6. **Conclusion**:
- Both the assertion and reason are true, and the reason correctly explains the assertion.

### Final Answer:
Both the assertion and reason are true, and the reason is the correct explanation of the assertion.

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