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    why is a bond between a sp2 hybridised carbon and a sp3 hybridised carbon stronger than a bond between two sp3 hybridised carbons?
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    (Original post by ScreamYourHeartOut)
    why is a bond between a sp2 hybridised carbon and a sp3 hybridised carbon stronger than a bond between two sp3 hybridised carbons?
    Isn't it due to the two clouds of electrons that form on the top and bottom of the single bond?
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    do you mean, for example, between the 1st and 2nd carbons in CH3CHCH2 ?

    I wasn't aware that it was stronger than a regular sp3-sp3 bond..

    hmm
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    like apparently ch3-ch=ch-ch3 is more stable than ch3-ch2-ch=ch2?
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    You can think of it in terms of partial charges and stability of the resulting ion if the bond breaks.

    A carbon that is more highly substituted, i.e. an sp3 carbon, is a more stable cation if one of the bonds breaks, leaving it with three substituents that can donate electron density to the carbocation. So an sp3-sp3 bond is relatively weak and doesn't mind breaking that much because the three substituents that are left can help neutralise the positive charge.

    An sp2 carbon on the other hand, is less substituted. So if one of the bonds were to break, it would be left with only two substituents: not stable, as these are unable to neutralise the charge as well as three substituents. Therefore an sp2-sp3 bond is stronger and doesn't like breaking.

    Hope that helps!
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    (Original post by Saunterer)
    You can think of it in terms of partial charges and stability of the resulting ion if the bond breaks.

    A carbon that is more highly substituted, i.e. an sp3 carbon, is a more stable cation if one of the bonds breaks, leaving it with three substituents that can donate electron density to the carbocation. So an sp3-sp3 bond is relatively weak and doesn't mind breaking that much because the three substituents that are left can help neutralise the positive charge.

    An sp2 carbon on the other hand, is less substituted. So if one of the bonds were to break, it would be left with only two substituents: not stable, as these are unable to neutralise the charge as well as three substituents. Therefore an sp2-sp3 bond is stronger and doesn't like breaking.

    Hope that helps!
    aha! Yes indeed. You are clever.
 
 
 
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