E and Z isomers
What E and Z isomers means in Chemistry A-Level, as defined for AQA.
Definitions of E and Z isomers
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Reference: AQA
Stereoisomers that share a structural formula but differ in spatial arrangement, labelled using CIP priorities rather than appearance.
Two distinct arrangements occur whenever each doubly bonded carbon carries two different groups, such as Z-but-2-ene and E-but-2-ene.
Topics that use E and Z isomers
- Isomerism (AQA A-Level)
Related terms
- atomic number comparison
- CIP priority rules
- E-Z isomerism
- first point of difference
- Optical isomerism
- restricted rotation
- stereoisomers
- structural isomer
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