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Heating 2-bromobutane with alcoholic KOH on the lab bench primarily gives:
ABut-2-ene, by E2 elimination via Saytzeff's rule
BButan-2-ol, by SN2 attack of OH$^-$ on the carbon centre
CButan-1-ol, by SN1 substitution after Br$^-$ leaves
DNo reaction, since KOH is too weak a base here
Answer & Solution
Correct answer: A. But-2-ene, by E2 elimination via Saytzeff's rule
Alcoholic KOH promotes E2 elimination; Saytzeff gives the more substituted alkene (but-2-ene).
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