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    I'm a second year chemistry student and am still really lost when it comes to this.
    If anyone could explain some basic principles of how they are drawn /give some examples/ link me to some useful pages, that would be really helpful.
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    You tried Chemguide?

    http://www.chemguide.co.uk/
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    (Original post by YesNoMaybeIDontKnow)
    I'm a second year chemistry student and am still really lost when it comes to this.
    If anyone could explain some basic principles of how they are drawn /give some examples/ link me to some useful pages, that would be really helpful.
    Mechanisms are named according to the attacking reagent and the overall effect.

    The attacking reagent may be a nucleophile, electrophile or a free radical.

    Nucleophile = seeking positive charge (always has a lone pair of electrons)
    Electrophile = seeking negative charge

    BUT the curly arrows always show the actual movement of electron pairs. Where they start off and where they reach out to.

    Look at this simple acid-base reaction:

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    The two simplest mechanisms to understand are shown below. The nucleophilic substitution can be more complex than shown, but this is a simplified form.



    Mechanisms follow all of the usual rules regarding particles and electronic charge. You cannot lose or gain matter or charge. Two opposite charges cancel out.

    It is possible however, that you read mechanisms in books where the leaving ion/atom is left out. This just means that you are expected to understand the rules outlined above.
 
 
 
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