Chemistry A-Level
longest chain
What longest chain means in Chemistry A-Level, as defined for AQA.
Definition of longest chain
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Reference: AQA
The longest continuous carbon chain that contains the principal functional group, from which the stem is taken.
Topics that use longest chain
- Nomenclature (AQA A-Level)
Related terms
- alphabetical prefixes
- Displayed formula
- General formula
- Homologous series
- IUPAC rules
- lowest locants
- Molecular formula
- difference of CH₂
Using longest chain in the exam
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