Summary
Characteristic organic reactions involve changes in the structure of organic molecules through various mechanisms.
- Electrophile — a molecule or ion that is electron-deficient and can accept electron pairs. Example: Bromine acts as an electrophile in the reaction with benzene.
- Electrophilic Substitution — a reaction where an atom or group in a molecule is replaced by an electrophile. Example: Benzene reacts with bromine to form bromobenzene.
- Addition Reaction — involves combining molecules to form a single product without removing atoms. Example: Hydrogenation of alkenes to form alkanes.
- Elimination Reaction — the reverse of addition, where a small molecule is removed from an organic molecule. Example: Elimination of HCl from an alkyl halide to form an alkene.
Exam Tips
Key Definitions to Remember
- Electrophile
- Electrophilic Substitution
- Addition Reaction
- Elimination Reaction
Common Confusions
- Confusing electrophilic substitution with addition reactions in aromatic compounds.
- Misunderstanding the difference between addition and elimination reactions.
Typical Exam Questions
- What is an electrophile? An electron-deficient molecule or ion that accepts electron pairs.
- How does benzene react with bromine? Through electrophilic substitution to form bromobenzene.
- What happens in an elimination reaction? A small molecule is removed, forming a double bond.
What Examiners Usually Test
- Understanding of reaction mechanisms like electrophilic substitution.
- Ability to identify and explain addition and elimination reactions.