CIP priority rules
What CIP priority rules means in Chemistry A-Level, as defined for AQA, OCR.
Definitions of CIP priority rules
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Reference: AQA
Rules applied to assign priorities to the groups on each doubly bonded carbon so that an alkene can be labelled E or Z.
Rules that decide which group on each end of a double bond takes priority, and therefore whether the isomer is E or Z.
Priority at each carbon is assigned using Cahn–Ingold–Prelog rules, where the higher atomic number wins.
Topics that use CIP priority rules
Related terms
- stereoisomers
- Structural isomers
- Addition polymerisation
- Addition polymerisation of alkenes
- Addition reactions forming other organic chemicals
- Atomic number and first point of difference
- atomic number comparison
- Biodegradable and renewable alternatives
Using CIP priority rules in the exam
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