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    Right I always get mixed up with electron densities.. Having a lower electron density, does it mean the molecule is more stable such as Benzene, because of its delocalised system keeping it fairly an unreactive molecule, or is it the other way round?
    And does Cyclohexene have a higher electron density where the double bond is in comparison to Benzene?
    Also, can someone just define electron density to me, in terms of chemistry.

    Much appretiated.
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    Lower electron density around a double bond gives rise to less reactive molecules, this is correct.

    Electron density is the likelihood of finding electrons in that particular area.
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    Higher Electron Density = More susceptible to electrophillic attack (hence more reactive to No2+ and bromine)

    Cycloehexene has C=C, which has localised electrons making it more electron dense than benzene. So it can undergo electrophillic addition reactions such as with bromine very easily. As it can induce a dipole in bromine without presence of a halogen carrier
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    (Original post by ramzy91)
    Higher Electron Density = More susceptible to electrophillic attack (hence more reactive to No2+ and bromine)

    Cycloehexene has C=C, which has localised electrons making it more electron dense than bromine. So it can undergo electrophillic addition reactions such as with bromine very easily. As it can induce a dipole in bromine without presence of a halogen carrier
    Ah, i get ya.. So Cyclohexene has a higher electron density than Benzene? Because the structure of Benzene has a system of delocalised electrons.. whereas the C=C in cyclohexene has localised electrons.. Ahh i get ya !!

    Thanks!
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    (Original post by Haz Shah)
    Ah, i get ya.. So Cyclohexene has a higher electron density than Benzene? Because the structure of Benzene has a system of delocalised electrons.. whereas the C=C in cyclohexene has localised electrons.. Ahh i get ya !!

    Thanks!
    Yup =)

    You're welcome
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    As a quick note, my teacher taught me a paragraph to remember as to why Phenol is more reactive than benzene which is a sure fire way to get the marks:

    "The lone pair of electrons on the oxygen interact with the delocalised electrons of the benzene ring. This leads to a greater area of electron density making the molecule more susceptible to electrophiles. The benzene ring has been activated"

    This should help you stop you getting mixed up on electron densities

    Bit off topic but hopefully this will help you out at some point!
 
 
 
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