CAIE IGCSE Chemistry Organic Substitution Definition
Practise recognising substitution when one atom or group is replaced by another and applying the term to halogen reactions of saturated hydrocarbons.
- Syllabus
- 2026–2028
- Course
- Chemistry 0620
Practise recognising substitution when one atom or group is replaced by another and applying the term to halogen reactions of saturated hydrocarbons.
The table shows the structures of four hydrocarbons.

Compound P undergoes a substitution reaction with chlorine.
What is meant by the term substitution reaction?
(one) atom or group is replaced by another (atom or group)