Answer: propene.
- A propan-2-ol
- B propan-1-ol
- C propene
- D propane
Correct answer: C. propene
Explanation: Alcoholic KOH promotes dehydrohalogenation (E2 elimination), giving propene; aqueous KOH would instead give the alcohol.
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.