In each of the following questions, a statement of statement I is given followed by a corresponding statement of statement II just below it of the statements; mark the correct answer.

Statement I: Phenol is more reactive than benzene towards electrophilic substitution.

Statement II: In the case of phenol, the intermediate carbocation is more resonance stabilized.

If both statement I and statement II are true and statement I is the correct explanation of statement II.

The correct answer is option 1. If both statement I and statement II are true and statement I is the correct explanation of statement II.

Let us break down the statements and the reasoning behind why the correct answer is:

Statement I: Phenol is more reactive than benzene towards electrophilic substitution.

Phenol, which has a hydroxyl group (-OH) attached to the benzene ring, is more reactive towards electrophilic substitution reactions compared to benzene itself. This increased reactivity is primarily due to the electron-donating nature of the -OH group through resonance and inductive effects. The lone pairs of electrons on the oxygen atom of the -OH group can delocalize into the benzene ring, thereby increasing the electron density on the ring and making it more susceptible to attack by electrophiles.

Statement II: In the case of phenol, the intermediate carbocation is more resonance stabilized.

During electrophilic substitution reactions involving phenol, the incoming electrophile (such as \( \text{E}^+ \)) initially forms a sigma complex (arenium ion) with the benzene ring. In phenol, the positive charge on the carbon atom of the sigma complex can be stabilized by resonance with the lone pairs of electrons on the oxygen atom of the -OH group. This resonance stabilization effectively spreads the positive charge over more atoms, reducing its magnitude and stabilizing the intermediate carbocation.

Analysis of the Statements

Statement I asserts that phenol is more reactive towards electrophilic substitution compared to benzene. This is true because the -OH group in phenol donates electron density to the benzene ring, making it more nucleophilic and facilitating the attack by electrophiles.

Statement II states that the intermediate carbocation formed during electrophilic substitution in phenol is more resonance stabilized. This is also true because the lone pairs on the oxygen atom of the -OH group can participate in resonance with the positive charge on the carbon atom that holds the electrophile. This resonance stabilization lowers the energy of the transition state and stabilizes the intermediate, enhancing the overall reactivity of phenol towards electrophilic substitution.

Explanation

Correct Explanation Relationship: Statement I provides the reason why Statement II is true. The increased reactivity of phenol (Statement I) is directly linked to the stabilization of the intermediate carbocation (Statement II) through resonance with the -OH group. The electron-donating nature of the -OH group in phenol facilitates both the initial attack by the electrophile and the stabilization of the resulting intermediate. Therefore, Statement I is the correct explanation of Statement II.

Conclusion: The correct answer, therefore, is: 1. If both statement I and statement II are true and statement I is the correct explanation of statement II.