A-LevelChemistryHalogen derivativesMay/June 2023Paper 1 Q321 Mark
Halogenoalkanes react with hot ethanolic potassium cyanide. The reaction mechanism is either Sɴ1 or Sɴ2. Which statement is correct?
AAll secondary halogenoalkanes react by the Sɴ2 mechanism only.
BBoth the halogenoalkane and the cyanide ion are involved in the initial step of the Sɴ1 mechanism.
CChloroethane reacts with cyanide ions by the Sɴ1 mechanism only.
DThe Sɴ2 mechanism involves a short-lived negatively charged transition state.
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The correct answer is D. This question tests the candidate's understanding of halogen derivatives within the Chemistrysyllabus. The examiner's mark scheme requires...
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