A statement of Assertion is given followed by a corresponding statement of Reason (R). Choose the correct answer from the given options.

Assertion: Addition reaction of water to but-1-ene in acidic medium yields butan-1-ol.

Reason: Addition of water in acidic medium proceeds through the formation of primary carbocation.

Both Assertion and Reason are incorrect

The correct answer is option 4. Both Assertion and Reason are incorrect.

Let us delve deeper into the statements and the reasons behind the correct answer.

Assertion: The statement claims that the addition reaction of water to but-1-ene in acidic medium yields butan-1-ol.

In reality, when water adds to but-1-ene in acidic medium, it undergoes an electrophilic addition reaction, forming a carbocation intermediate. However, due to the presence of the acidic medium, the carbocation intermediate undergoes further reactions before the addition of a water molecule to form butan-1-ol. Instead, the reaction typically proceeds through a Markovnikov addition mechanism, resulting in the formation of a ketone rather than an alcohol. Specifically, the product formed is 2-butanone (also known as methyl ethyl ketone), not butan-1-ol.

Reason: The reason provided suggests that the addition of water in acidic medium proceeds through the formation of a primary carbocation.

However, this statement is also incorrect. In the addition of water to but-1-ene in acidic medium, the intermediate carbocation formed is a secondary carbocation, not a primary one. This is because the positive charge in the carbocation intermediate is stabilized by the neighboring carbon atom, leading to the formation of a secondary carbocation. Primary carbocations, which have the positive charge directly attached to a primary carbon, are less stable and less likely to form in this reaction.

Explanation of the Correct Answer

Given that both the Assertion and Reason are incorrect:

The assertion incorrectly states the product of the reaction.

The reason incorrectly describes the formation of the carbocation intermediate.

Therefore, the correct option is indeed : Both Assertion and Reason are incorrect

This explanation highlights the importance of understanding reaction mechanisms and the roles of different factors, such as the presence of acidic medium and the stability of carbocation intermediates, in organic chemistry reactions.