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    Can someone please explain to me how I know when a question asking about mechanisms is wanting me to answer via free radical substitution, electrophillic addition, or nucleophillic addition?
    what do I have to have present in order to use each of these mechanisms???
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    (Original post by libbyx)
    Can someone please explain to me how I know when a question asking about mechanisms is wanting me to answer via free radical substitution, electrophillic addition, or nucleophillic addition?
    what do I have to have present in order to use each of these mechanisms???
    Radical substitution is usually just Br2 Cl2 or formation of Ozone ect, or if they expect you to do with with another molecule, it would usually say that it reacts in a similar way to Br2 ect indicating that it wants you to show radical substitution.
    Electrophilic addition for AS you only really do electrophilic addition for a molecule with a double bonded Carbon in it C=C, so whenever you see a C=C your mind should think of one of two options, either electrophilic addition or addition polymerisation
    Here's an example:
    Spoiler:
    Show

    The other one you need to know about is nucleophilic substitution and you'll find that the only example you need to know (and then apply like in similar molecules) is of halogenoalkanes, but you'll also need to know the rates and factors of this and such.
    Like this one for example:
    Spoiler:
    Show

    You mainly just need to show the stages for these processes, the movement of pairs of electrons, the breaking of covalent bonds, the (partial) charges

    A good overview of all the mechanisms you need to know is in the textbook (you're probably doing the new spec so I shan't instruct you what page in the book it is, but in my old textbook the page is just called reaction mechanisms)
 
 
 
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