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JEE Main202524 Jan 2025Morning ShiftChemistryHydrocarbonsActual

Following are the four molecules "P", "Q", "R" and "S". Which one among the four molecules will react with H - Br _ ( aq ) at the fastest rate?

Options

  1. AR
  2. BP
  3. CQ
  4. DS

Correct answer

C. Q

Step-by-step solution

Addition of H - Br _ ( aq ) to alkene follows electrophilic addition mechanism. In the rate determining step a carbocation intermediate is formed. Among P , Q , R & S compound Q will form most stable carbocation intermediate since it is resonance stabilized.

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