Assertion (A) Addition reaction of water to but-1-ene in acidic medium yields butan-1-ol.
Reason (R) Addition of water in acidic medium proceeds through the formation of primary carbocation.
(a)Assertion and reason both are correct and reason is correct explanation of assertion.
(b)Assertion and reason both are wrong statements.
(c)Assertion is correct statement but reason is wrong statement.
(d)Assertion is wrong statement but reason is correct statement.

Options

A. Assertion and reason both are correct and reason is correct explanation of assertion.
B. Assertion and reason both are wrong statements.
C. Assertion is correct statement but reason is wrong statement.
D. Assertion is wrong statement but reason is correct statement.

Explanation

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

### Step 1: Analyze the Assertion
The assertion states: "Addition reaction of water to but-1-ene in acidic medium yields butan-1-ol."

- **But-1-ene** has the structure: CH3-CH2-CH=CH2.
- When water is added in the presence of an acid (H+), the reaction follows Markovnikov's rule, which states that the hydrogen atom from the water will attach to the carbon with more hydrogen atoms (the less substituted carbon), and the hydroxyl group (OH) will attach to the more substituted carbon.
- Therefore, the product formed will be **butan-2-ol**, not butan-1-ol.

**Conclusion**: The assertion is **incorrect**.

### Step 2: Analyze the Reason
The reason states: "Addition of water in acidic medium proceeds through the formation of a primary carbocation."

- In the reaction mechanism, when but-1-ene reacts with water in acidic medium, the double bond shifts to form a carbocation.
- The carbocation formed is actually a **secondary carbocation**, not a primary one, because the positive charge is on the second carbon (which is more stable than a primary carbocation).

**Conclusion**: The reason is also **incorrect**.

### Final Conclusion
Both the assertion and the reason are incorrect. Therefore, the correct answer is:
**(b) Assertion and reason both are wrong statements.**

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