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    if you add bromine to hexene, where would the 2 Br go?

    what's the difference between racemic mixture and optically active and how can you tell which is which?

    thanks
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    a racemic mixture is one that contains 50:50 ratio of + and - enantiomers, so each rotate plane of polarised light, equally and in opposite directions, so no overall rotation, so it is not optically active
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    an optically active one will rotate the plane of polarised light
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    the 2 Br join to the 2C in the C=C to form C-C
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    thanks a lot dave!

    one thing...how would you know if it is 50:50? vand how would you know if it rotates the plane of polarised light?
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    It is 50:50 when the one of the C=C carbons has a planar shape (e.g. 3BP 0LP => triganl planar)..This means it has 2 planes and so the substance attancink can atack from both sides
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    Trignal planar
    3BP 0 LP (the double bond is taken as 1 BP)
    Ive drawn a crapy pic below hehe
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    check this link out for an animation of optical rotation

    http://scholar.hw.ac.uk/site/chemistry/clicker.swf
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    and this one fro an explanation
    http://www.ibchem.com/IB/ibc/organic...somers.htm#opt
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    thanks v much guys

    i get it now
 
 
 
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