Condensation Reactions
Condensation
Two molecules join together with the loss of a small molecule (usually H₂O).
| Type | Reactants | Product | Bond Formed |
|---|---|---|---|
| Esterification | Carboxylic acid + Alcohol | Ester + H₂O | C–O (ester linkage) |
| Amide formation | Carboxylic acid + Amine | Amide + H₂O | C–N (amide / peptide bond) |
Hydrolysis Reactions
Hydrolysis
The reverse of condensation. A bond is broken by the addition of water, splitting the molecule into two smaller ones.
💡 Acid vs Base Hydrolysis
- Acid hydrolysis: Reversible. Ester + H₂O ⇌ acid + alcohol (H⁺ catalyst)
- Base hydrolysis (saponification): Irreversible. Ester + NaOH → sodium salt of acid + alcohol
📋 Exam Tip
Base hydrolysis of esters is irreversible because the carboxylate ion (COO⁻) formed is stabilised by resonance and does not reform the ester. This is why base hydrolysis goes to completion.