Rate of reaction in E₁ depends on the:
Correct answer: A. R-X only
- A. R-X only
- B. Base only
- C. Nucleophile only
- D. Both base and R-X
Explanation
E1 is a unimolecular elimination whose slow step is the ionisation of the alkyl halide to a carbocation, so the rate depends on the concentration of R X only. The base acts only in the fast second step, which is why it does not appear in the rate equation, unlike E2.
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About Elimination Reactions
Elimination reactions remove a leaving group and a hydrogen atom from adjacent carbon atoms to form an alkene. The topic covers dehydrohalogenation of alkyl halides, E1 and E2 mechanisms, the role of base, solvent and substrate structure, and Zaitsev orientation, which is often contrasted with substitution.
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