Ks and Ke, are respectively, the rate constants for substitution and elimination and the correct options is- Aand Ke(A) > Ke(B)
- Band Ke(B) > Ke(A)
- Cand Ke(B) > Ke(A)
- Dand Ke(A) > Ke(B)
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Correct answer: B
The figure/reactions are not visible in the prompt, so I infer this is the standard comparison between two alkyl halides/reaction conditions where:
- = rate constant for substitution
- = rate constant for elimination
We must compare both:
- the ratio for reactions and
- the elimination rate constants and
1. Meaning of
If
then reaction/pathway is relatively more substitution-favoured than .
If
then reaction/pathway is more substitution-favoured.
Also, a larger means elimination is faster in that case.
2. Standard organic trend used in such questions
For haloalkanes under conditions where substitution and elimination compete:
- Elimination is favoured more for the substrate/condition with greater steric hindrance / more substituted carbon / stronger tendency to form alkene.
- Substitution is favoured more for the less hindered case.
Thus, if case is the one where elimination is more favourable, then:
and because substitution is relatively less favoured in ,
So the correct comparison becomes:
3. Match with options
This corresponds to Option B.
4. Final answer
So, Option B is correct.
5. Comparison with stored answer
Stored correct answer = B.
My derived answer also = B. Hence they agree.
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