Homologous series
What Homologous series means in Combined Science GCSE, as defined for AQA.
Definitions of Homologous series
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Reference: AQA
A family of compounds with the same general formula and similar chemical properties, in which each member differs from the next by a CH₂ unit.
A family with the same general formula, similar reactions and a gradual change in physical properties as chain length increases.
A series such as the alkanes, where each member differs by a CH₂ unit and the trend applies across it.
A series whose pattern allows you to predict the formula of the next member.
Topics that use Homologous series
- Crude oil, hydrocarbons and alkanes (AQA GCSE)
- Fractional distillation and petrochemicals (AQA GCSE)
- Properties of hydrocarbons (AQA GCSE)
Related terms
- Crude oil
- Fractional distillation
- Boiling point
- Chemical reactions
- Combustion products
- Complete combustion
- Cracking and alkenes
- Energy transfer
Using Homologous series in the exam
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