Identify the correct statement(s):
- Bakelite and urea formaldehyde resin are elastomers
- Poly amides like nylon 6 and nylon 6,6 are the examples of fibres.
- Polystyrene, polyvinyl and polythene are thermoplastic polymers
- Thermoplastic polymers have intermolecular forces between elastomers and fibres.
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → B, C and D only
Polymers are classed by the intermolecular forces between their chains: elastomers (weakest), thermoplastics (intermediate), fibres (strongest), and thermosetting polymers, which form cross-links on heating.
(A) Bakelite and urea formaldehyde resin are elastomers — False. Both are thermosetting polymers: on heating they cross-link into a hard, infusible mass. Elastomers are rubber-like, such as buna-S and neoprene.
(B) Poly amides like nylon 6 and nylon 6,6 are the examples of fibres. — True. Hydrogen bonds between the polyamide chains give them high tensile strength.
(C) Polystyrene, polyvinyl and polythene are thermoplastic polymers — True. These linear or slightly branched polymers soften on heating and harden on cooling again and again.
(D) Thermoplastic polymers have intermolecular forces between elastomers and fibres. — True. Their forces are stronger than in elastomers and weaker than in fibres.
Note: This question is from the pre-rationalised NCERT book (2022-23). The topic is not there in the latest NCERT book (2026-27), and it is also out of the CUET 2026 syllabus.
NCERT (Pre-rationalised edition, 2022-23):
Fibres
