Identify the incorrect statement
A. Bakelite and urea-formaldehyde resins are elastomers
B. Polyamides like nylon 6, nylon 6, 6 are examples of fibers.
C. Polystyrene, polyvinyl chloride and polythene are thermoplastic polymers.
D. Thermoplastic polymers have intermolecular force between elastomers and fibers.
Choose the most appropriate answer from the option given below:
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → A only
Polymers are classed by the intermolecular forces between their chains: elastomers (weakest), thermoplastics (intermediate), fibres (strongest, hydrogen bonds), and thermosetting polymers, which cross-link on heating.
(A) Bakelite and urea-formaldehyde resins are elastomers — Incorrect. Both are thermosetting polymers: on heating they cross-link into an infusible mass and cannot be reused. Elastomers are rubber-like polymers such as buna-S and neoprene.
(B) Polyamides like nylon 6, nylon 6, 6 are examples of fibers. — Correct. Strong hydrogen bonds between the polyamide chains give high tensile strength.
(C) Polystyrene, polyvinyl chloride and polythene are thermoplastic polymers. — Correct. They soften on heating and harden on cooling again and again.
(D) Thermoplastic polymers have intermolecular force between elastomers and fibers. — Correct. Their forces are stronger than in elastomers and weaker than in fibres.
Note 1: 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):
Thermoplastic Polymers
Note 2: The same/similar question has been asked in different years by NTA as per the details given below:
| 2026 | 2025 | 2024 | 2023 | 2022 |
|---|---|---|---|---|
| – | – | – | 02-06 S3 31-05 S1 | – |