Exams › NEET › Chemistry › Polymers
45 questions with worked solutions.
Q1. PVC is prepared by the polymerisation of:
Answer: 1-chloroethene
PVC is poly(vinyl chloride), so its monomer must be vinyl chloride, also called 1-chloroethene. During addition polymerization, the C=C bond opens and links many 1-chloroethene units into the polymer chain.
Q2. Isotactic polypropylene polymer is one, in which:
Answer: all methyl groups are on one side of the extended chain. It is a highly crystalline, has high melting point and forms strong fibres
Isotactic polypropylene has all the methyl groups oriented on the same side of the polymer chain, giving a very regular structure. This regularity lets chains pack tightly, so it is highly crystalline with a higher melting point and stronger fibers.
Q3. The polymer used for post operative stitches is:
Answer: poly lactic acid
Poly lactic acid is a biodegradable polymer used in absorbable sutures, so it is suitable for post-operative stitches. The other options are either monomers, less appropriate materials, or not the standard suture choice here.
Q4. Nylon-6 is prepared by linear condensation homopolymerization reaction of:
Answer: 6 -aminohexanoic acid
Nylon-6 is formed by condensation polymerization of 6-aminohexanoic acid, which contains both functional groups needed to link repeatedly into a polyamide. The other options correspond to different polymers or nylon-6,6.
Q5. Frying pan handles are made up of
Answer: thermosetting Plastic
Frying pan handles must withstand high temperatures without deforming, so they are made from thermosetting plastics. These plastics harden permanently on heating and do not soften again like thermoplastics.
Q6. Polymerization in which two or more chemically different monomers take part is called:
Answer: Copolymerization
Copolymerization is the polymerization of two or more different monomers into the same polymer chain. The other choices describe either a mechanism (addition/chain polymerization) or use of only one monomer type (homopolymerization).
Q7. Which of the following is used as life saving substance as blood plasma?
Answer: Polyvinyl pyrrolidone
Polyvinyl pyrrolidone (PVP) is a water-soluble synthetic polymer that has been used as a plasma substitute/plasma expander in life-saving situations. The other options are not used for this medical purpose: cellulose is a structural polymer, Teflon is a nonstick fluoropolymer, and Bakelite is a thermosetting plastic.
Q8. The role of zinc stearate in the process of vulcanisation is:
Answer: to accelerate the process
Zinc stearate is used to speed up vulcanisation by helping the curing agents work more effectively. It does not initiate or stop the process; it mainly improves the rate of cross-linking.
Q9. Nylon-66 is an example of:
Answer: polyamide
Nylon-66 is formed by condensation polymerization and its chain contains repeating amide (–CONH–) groups, which is the defining feature of polyamides. Therefore, it belongs to the polyamide family, not polyester or the other listed polymers.
Q10. Which of these is not a monomer for a high molecular mass silicone polymer?
Answer: Me3SiCl
Me3SiCl is not a monomer for high molecular mass silicone polymers because it lacks the necessary functionality to form a polymer chain, as it has only one reactive site.
Q11. The straight chain polymer is formed by:
Answer: Hydrolysis of (CH3)2SiCl2 followed by condensation polymerisation
The hydrolysis of (CH3)2SiCl2 followed by condensation polymerization forms a straight-chain polymer due to the two reactive sites on the silicon atom, allowing linear polymer formation.
Q12. Which of the following is a natural polymer?
Answer: cis-1, 4-polyisoprene
Cis-1,4-polyisoprene is a natural polymer as it is the main component of natural rubber, derived from latex of rubber trees. The other options are synthetic polymers.
Q13. The biodegradable polymer is:
Answer: nylon-2-nylon-6
Nylon-2-nylon-6 is a biodegradable polymer because it is made from glycine and amino caproic acid, which are naturally occurring monomers.
Q14. Which one of the following is not a condensation polymer?
Answer: Neoprene
Neoprene is an addition polymer formed by the polymerization of chloroprene, unlike the others which are condensation polymers.
Answer: Polyamide
Nylon is a synthetic polymer classified as a polyamide because it contains amide linkages (-CONH-) in its structure.
Q16. −NH(CH2)6 NHCO(CH2)4 CO−n− is a:
Answer: copolymer
The given polymer contains two different monomer units, one with an amide group and another with a carbonyl group, indicating it is a copolymer formed by the condensation of two distinct monomers.
Q17. Of the following which one is classified as polyester polymer?
Answer: Terylene
Terylene is a polyester polymer formed by the condensation polymerization of terephthalic acid and ethylene glycol, while the others are not polyesters.
Q18. Which one of the following is a chain growth polymer?
Answer: Polystyrene
Polystyrene is a chain growth polymer formed by the addition polymerization of styrene monomers, unlike starch, nucleic acids, or proteins, which are step-growth polymers or biopolymers.
Q19. In elastomer, intermolecular forces are:
Answer: weak
Elastomers have weak intermolecular forces, allowing their polymer chains to stretch and return to their original shape, which is a characteristic property of elastomers.
Q20. Natural rubber has
Answer: all cis-configuration
Natural rubber is composed of polyisoprene chains where the double bonds are in the cis-configuration, which gives it elasticity.