Question

    Which of the following organic compounds undergo

    nucleophilic substitution reaction most easily?
    A CH₃Cl Correct Answer Incorrect Answer
    B CH₃Br Correct Answer Incorrect Answer
    C CH₃I Correct Answer Incorrect Answer
    D CH₃F Correct Answer Incorrect Answer

    Solution

    The rate of a nucleophilic substitution reaction depends heavily on how easily the leaving group (halogen atom) can depart from the molecule. In alkyl halides like CH₃X (X = halogen), the leaving group ability follows this trend: I -  >  Br -  >  Cl -   >  F -  This is because: Iodide (I⁻) is the largest and least basic halide ion, and thus it leaves most easily. Fluoride (F⁻) is small and strongly bonded to carbon, making it a poor leaving group.

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