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    When should we use E/z isomers instead of cis and trans? please give examples as well.


    i always thought that they were the same thing but apparently im wrong.

    Thank you!
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    What specification are you doing?
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    This should offer some insight: http://www.chemguide.co.uk/basicorg/isomerism/ez.html

    I missed our lesson on E/Z isomerism and the few pages on geometric isomerism on that site brought me up to speed.
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    E/Z is used when referring to the priorities of the allylic groups across the double bond.
    When the two highest priority groups are on the same side, they are Z isomers, when the are on opposite sides they are E. It is more accurate that cis/trans in the sense that, with more than three substituents, it may be confusing with cis/trans notation to which you are referring.
    E/Z also can only be used with alkenes.

    Cis/trans is perfectly acceptable nomenclature when only two groups are attached to across a double bond. It is also the chosen way of referring to other sterically inhibited systems, like rings.
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    (Original post by Nidfeo)
    What specification are you doing?
    edexcel
 
 
 
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