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    Hi all ..
    Is there anyone who studying organic chemistry can advice me how to study the SN1 , SN2 , E1 , and E2 reactions ??
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    (Original post by Nada Billy)
    Hi all ..
    Is there anyone who studying organic chemistry can advice me how to study the SN1 , SN2 , E1 , and E2 reactions ??
    SN1 vs SN2 is a very important open-ended case study discussion in A-Level and possibly at AS also for some exam boards.

    Think of what Sn1 means
    - 1st order reaction - single molecule in the slowest step of the reaction
    - it has two steps (first step is the slowest)
    - it has double hump for the energy profile diagram - with carbocation intermediate in the middle trough
    - hmmm...that is a carbocation, from a alkyl halide...how? break C-X bond...how... heterolytic fission...how? on its own obviously (see first point - only 1 molecule in the slowest first step).
    - draw mechanisms again and again with different examples

    Sn vs En is a common first year university chemistry case study, possibly in A-Level also i suppose.
    - aq NaOH in water promotes nucleophilic substitution (hydrolysis) of RX to ROH
    - NaOH in ethanol promotes elimination of RX to alkenes

    Hmm, why, how? read up on chemguide further, but not before you can even differentiate Sn1 and Sn2.

    Now I am sure some textbook reading would be beneficial, as would talking to people, as would chemguide as well.

    Good luck.
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    (Original post by shengoc)
    SN1 vs SN2 is a very important open-ended case study discussion in A-Level and possibly at AS also for some exam boards.

    Think of what Sn1 means
    - 1st order reaction - single molecule in the slowest step of the reaction
    - it has two steps (first step is the slowest)
    - it has double hump for the energy profile diagram - with carbocation intermediate in the middle trough
    - hmmm...that is a carbocation, from a alkyl halide...how? break C-X bond...how... heterolytic fission...how? on its own obviously (see first point - only 1 molecule in the slowest first step).
    - draw mechanisms again and again with different examples

    Sn vs En is a common first year university chemistry case study, possibly in A-Level also i suppose.
    - aq NaOH in water promotes nucleophilic substitution (hydrolysis) of RX to ROH
    - NaOH in ethanol promotes elimination of RX to alkenes

    Hmm, why, how? read up on chemguide further, but not before you can even differentiate Sn1 and Sn2.

    Now I am sure some textbook reading would be beneficial, as would talking to people, as would chemguide as well.

    Good luck.
    Thanks a lot 😉
 
 
 
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