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E z isomerism

So I'm learning about e z isomerism I was wondering if the highest priority groups r on the same side e.g. u have the chlorine molecules on the left side and 2 hydrogen molecules on the right side would that be z isomerism or would it not be an isomer? Do the atoms have to be different
Original post by Anonymous
So I'm learning about e z isomerism I was wondering if the highest priority groups r on the same side e.g. u have the chlorine molecules on the left side and 2 hydrogen molecules on the right side would that be z isomerism or would it not be an isomer? Do the atoms have to be different


Nope, you need different atoms on C1 and C2 (what I'm calling the 2 c atoms in the double bond) so that one of them is highest priority. Of course, the 4 atoms overall attached to the carbons don't need to all be different, but the 2 attached to each carbon need to be different.
For instance, each of the carbons in the double bond could have a chlorine and a hydrogen atom on, it doesn't matter if each of the 2 carbon has the same groups attached to them, but on each carbon, they need to be different.
That explanation felt like it makes no sense so do ask any questions if you're still confused!
Reply 2
Original post by Anonymous
So I'm learning about e z isomerism I was wondering if the highest priority groups r on the same side e.g. u have the chlorine molecules on the left side and 2 hydrogen molecules on the right side would that be z isomerism or would it not be an isomer? Do the atoms have to be different

I think basically that if you have two of the same atom or group attached to the same carbon in a double bond then there is no E Z isomers.
Just an aside- be careful with terminology! They aren't chlorine molecules and incorrect terminology can cost marks in other areas of the syllabus- structure and bonding for example. Just a heads up!

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