Chapter summary
Polymers and Organic Chemistry, at a glance
Read organic structures, predict reactions and explain why a protein or plastic behaves as it does.
A-Level 8873, revised syllabus (2026-2027)
Quick revision
Revisit the essentials, then return to an explanation when you need it.
- Locate the group
Mark C=C, C-X, OH, C=O, COOH, COO or CONH.
- Read the conditions
Aqueous vs ethanolic NaOH, oxidant vs reductant, and acid vs alkali hydrolysis change the answer.
- Preserve the skeleton
Change only the reacting bonds; include small products, charge and counter-ions as needed.
- Check the result
Conserve atoms and charge, then name the new functional group and product.
| Pair | Deciding point |
|---|---|
| Constitutional / cis-trans | Different connections / same connections with restricted C=C arrangement. |
| Ester / amide | Carbonyl C attached to O / N. Acid + amine requires DCC for the specified amide route, not simple acid-base mixing. |
| Acid / alkali hydrolysis | Acid medium retains COOH and protonates amines; alkali gives COO- and unprotonated amine/ammonia products. |
| Denaturation / hydrolysis | Loss of the specific fold / cleavage of covalent peptide links. |
| Thermoplastic / thermoset | Separate chains can move on warming / covalent crosslinks prevent ordinary remelting. |
Named materials: LDPE branches pack less closely than HDPE; nylon 6,6 has stronger interchain hydrogen-bonding opportunities than PET; PVA OH groups hydrate with water whereas PVC is water-resistant; PP resists the ester hydrolysis that can damage PET in strong alkali.
Polyalkene inertness makes biodegradation difficult. Ester/amide links permit hydrolysis, but real rates depend on conditions. Recycling decisions must include economic, environmental and social consequences, not only a recovery percentage.