Shib Sagar posted an Question
September 21, 2020 • 07:00 am 30 points
  • IIT JAM
  • Chemistry (CY)

Please solve this problem

(a)i 33 Which of the following has lowest pK, value? , (a) ghjkk

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    Dinesh khalmaniya 1

    option D is correct

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    in option D, there is locking of molecule so restricted rotation. and it shows resonance in whole molecule. so most stable

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    A,B,C are non planar due to presence of bulky group so resonance is not possible in whole molecule

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    triphenylmethylcarbanion

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    Priyanshu kumar Best Answer

    Option D is most acidic so it has least pka value

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    for D, it is planar molecule due to restricted rotation of benzene rings. and have maximum resonance.

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    C is also planar but less Resonance than D so less acidic.

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    A and B are non planar due to bulky groups..

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    Due to this the resonance diminishes

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    sir -ve phenyl grp toh stable karta hai na agar 1st option mai crowding hai bhi but 2nd wale mai toh crowding kam hai na

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    nhi shib...yha fourth me dekho restricted rotation hai so negative charge pure ring se stabilised higa

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