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    why is it D ?
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    D coz if you flip them round you get e and z isomers whereas on the others if you flip atoms on one side of double bond it is the same
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    (Original post by Hassan2578)
    D coz if you flip them round you get e and z isomers whereas on the others if you flip atoms on one side of double bond it is the same
    I didn't get ur point . Do u mean by flipping , rotation ? Cuz if u mean rotation it can't be Cuz double bonds r rigid
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    Try drawing them out. Only from option D will each C from the C=C double bond be linked to unique chains, giving it E/Z isomerism
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    PS Reviewer
    You can't rotate around a double bond

    As others have said, it's easiest to draw them out. Or, you can use the rule that if there are two different things on each carbon then it must exhibit E/Z isomerism (e.g. ABC=CAB, ABC=CDE etc.).

    Google "ChemGuide" and there's a really great website explaining stuff like this
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    If you take the double bond as your starting point and draw the CH3 and H on either side you will see both CH3's could either be the 'bottom' bonded group, either be both the 'top' bonded group or be opposites with one being on 'top' and one being on the 'bottom'.

    In an E stereoisomer the groups are on opposite sides whereas with the Z they are on the same. It was far easier when they were called cis and trans.
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    (Original post by mgy2000)
    why is it D ?
    The answer is D because there are two of the same groups on each carbon of the C=C double bond
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    thnx all
 
 
 
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