Answer: Cyclohexyl chloride has a higher dipole moment due to no resonance reduction of the C-Cl dipole.
- A Chlorobenzene has a higher dipole moment because resonance enhances the C-Cl bond polarity
- B Cyclohexyl chloride has a higher dipole moment due to no resonance reduction of the C-Cl dipole
- C Both compounds show exactly equal dipole moments within experimental error
- D Neither compound shows any measurable dipole moment at all
Correct answer: B. Cyclohexyl chloride has a higher dipole moment due to no resonance reduction of the C-Cl dipole
Explanation: In chlorobenzene, the lone pair on Cl delocalises into the ring (resonance), reducing the C-Cl bond polarity. In cyclohexyl chloride (sp³ carbon), no such resonance occurs, so the C-Cl dipole is larger.
SN2 proceeds in a single step with backside attack and inversion of configuration, while SN1 forms a planar carbocation intermediate first, leading to racemisation.
Concept context
Study carbon-halogen compounds: how they are made, how they react via SN1/SN2 and elimination, their stereochemistry, and their environmental impact.