SN1 Mechanism Features Stabilized Carbocation Intermediate

Steps:

• Haloalkane undergoes heterolytic cleavage of C-X bond, forming a carbocation intermediate.
• Carbocation stability increases with adjacent alkyl groups via hyperconjugation and inductive effects.
• Nucleophile then attacks the planar carbocation from either side.
• Rate-determining step is carbocation formation, leading to racemization.

Why C is correct:

• In SN1, the carbocation intermediate follows Zaitsev's rule analog, where adjacent alkyl groups donate electrons to stabilize the positive charge through hyperconjugation.

Why the others are wrong:

• A: SN1 involves nucleophilic attack on the carbocation, not substitution of nucleophile by electrophile.
• B: The carbocation forms from unimolecular dissociation of one haloalkane molecule.
• D: The intermediate is a positively charged carbocation, not uncharged.

Final answer: C