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    Hi
    I have a couple of questions about which compound is more basic
    1) pho- or ch3c=oo-. I though they both have resonance so fro both of them the avaliability of the long pair is reduced. But then i don't know
    2) pho- or phs-. Ive written down pho- is a stronger base but this has confused me as s is larger so would be more able to help a negative charge so surely phs- should be a stronger base.

    Thanks
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    (Original post by sarah170194)
    Hi
    I have a couple of questions about which compound is more basic
    1) pho- or ch3c=oo-. I though they both have resonance so fro both of them the avaliability of the long pair is reduced. But then i don't know
    2) pho- or phs-. Ive written down pho- is a stronger base but this has confused me as s is larger so would be more able to help a negative charge so surely phs- should be a stronger base.

    Thanks
    As a general guide
    Carboxylic acids have a pKa of ~ 5.
    Phenol pKa ~ 10

    Hence phenoxide is a stronger base than a carboxylate.


    As for thiophenol, you are correct that the larger S stabilises a negative charge more. You are confusing yourself regarding acids/bases though.

    You know that acidity is related to the stability of the conjugate base. Hence, the more stable thiophenol anion is less basic (as the protonated form is more acidic).
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    (Original post by sarah170194)
    Hi
    I have a couple of questions about which compound is more basic
    1) pho- or ch3c=oo-. I though they both have resonance so fro both of them the avaliability of the long pair is reduced. But then i don't know
    2) pho- or phs-. Ive written down pho- is a stronger base but this has confused me as s is larger so would be more able to help a negative charge so surely phs- should be a stronger base.

    Thanks
    Hi

    Can you please keep your question to one thread instead of starting a new one? It helps us to keep track.

    Thanks

    http://www.thestudentroom.co.uk/show....php?t=2214573
    http://www.thestudentroom.co.uk/show....php?t=2214492
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    ok sorry
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    (Original post by sarah170194)
    ok sorry
    no problem. You're new here
 
 
 
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