CBSE Class 12 Chemistry Polymers Worksheet Set 02

Question. Give the name and structure of reagent usedfor initiating a free radicalchainreaction .
Answer : Name- benzoylperoxide ,C₆H₅-CO-O-O-CO-H₅C₆

Question. Classify them as addition and condensation polymers:Nylon-66,Buna-s,polythene,terylene
Answer : Additionpolymer:Polythene and Buna-s,Condensationpolymer:Nylon-66,terylene

Question. Give name and structure of monomer present in natural rubber.
Answer : Name:Isoprene(2-Methyl1,3-Butadiene) ,Structure:CH₂=C(CH₃) CH=CH₂

Question. What is biodegradeablepolymers?Give one example
Answer : PHBV

Question. What is polymers?
Answer : Polymers are high molecularmass substances consisting of large no of repeating structural units.

Question. How are the polymer classified on the basis of structure:
Answer : a) Linear Polymer b) Branched chain polymers c) Cross linked polymers

Question. Writes the names of monomer of the following (-CO-(CH₂) 5-NH-) n
Answer : Caprolactum

Question. Arrange the following polymers in increasing order of their intermolecular forces: Nylon6, Neoprene, polyvinyl chloride.
Answer : Neoprene<Polyvinyl chloride<Nylon-6 

Question. Is (-NH-CHR-Co-) n is a homopolymer or copolymer?
Answer : Homopolymer

Question. What is vulcanized rubber?
Answer : process of heating a mixture of natural rubber with sulphur is called vulcanized rubber.

Question. Write the monomer of Bakelite.
Answer : Phenol and formaldehyde

Question. Menton two uses of Bakelite.
Answer : It is used for making combs,electrical switches and handle of various utensils

Question. Explain the term copolymer and give two examples.
Answer : Polymer which are made up of two different monomer unit are called copolymers: eg.Buna-N,Buna-S (CH-15)

Question. Mention one use of melamine?
Answer : It is used in the manufacture of unbreakable crockery.

Question. How can natural rubber be made more tough?
Answer : By the process of vulcanization with sulphur.

Question. What is natural rubber?
Answer : It is a cis 1,4-polyisoprene.

Question. How do you explain functionality of monomer?
Answer : No of bonding sites in monomers.

Question. What are natural polymers?
Answer : Those polymers which are obtained mostly from plants and animals are called natural polymers eg Natural rubber,cellulose

Question. What is synthetic polymers?
Answer : Those polymer which are obtained from chemical compound are called synthetic polymer

Question. What is monomer of Nylon-2-Nylon-6?
Answer : Glycine,6-Aminocaproic acid.

Two marks questions on polymer

Question. Explain the difference between Buna-N and Buna-s.
Answer : Buna-Nis a polymer of 1,3-Butadiene and andacrylonitrile and buna-s is a polymer of 1,3-Butadiene and styrene.

Question. Distinguish between homopolymer and copolymer?
Answer : Homopolymer is made up of only one type of monomer unit eg. PVC. Where as co-polymer is made up of two different monomer units eg Buna-s.

Question. What are polyamides and polyesters?Give one example of each.
Answer : Polymers having amide linkage in the chain are called polyamides eg Nylon-6.Polymers having ester linkage in the chain are called polyesters eg. Terylene.

Question. Dicuss the main purpose of vulcanization.
Answer : Natural rubberbecome soft at high temperature,Brittle at low temperature.And show higher water absorption capacity. It is nonresistant to attack by oxidizing agent .In order to improve these properties a process of vulcanization is carried out.

Question. In which classes, the polymers are classified on the basis of molecular forces?
Answer : Elastomer, fibre ,thermoplastics and thermosetting polymers.

Question. Write names of monomers of the following polymers.
a) (-CF^2-CF^2-) n b) (CH^2-CH(cl)^-) n.
Answer : a) Tetrafluoroethene b) Vinyl chloride .

Question. what are monomeric repeating units of nylon-6 and nylon-6,6 ?
Answer : Caprolactam , Hexamethylenediamine and Adipic acid

Question. Arrange the following polymers in increasing order of their intermolecular forces.
a) nylon-6 ,6 ,Buna-S , Polythene
b) Neoprene, Nylon-6, PVC
Answer : a) BUNA-S< Polythene <Nylon-6,6
b) Neoprene < PVC < nylon-6

Question. Classify the following as Addition and condensation polymers: Bakelite,melamine,PVC,Buna-S,Buna-N,Nylon-6,6
Answer : Additionpolymers:Buna-N,Buna-S,PVC
Condensation polymer:Nylon-6,6,Bakelite melamine,

Question. How is novolac converted into bakelite?
Answer : Novolac on heating with formaldehyde undergoes crosslinking to form an infusible solid mass called Bakelite.

Question. Differentiate between Addition and condensation polymers.
Answer : Addition polymer:1) It takes place in unsaturated monomers.
2) Loss of small molecule like water and ammonia does not take place.

Two marks questions,Polymer

Condensation polymer: 1) It takes place in monomers having multi functional groups .2) Loss of small molecules like water and ammonia takes place.

Question. Differentiate between thermoplastic and thermosetting polymer.
Answer : Those polymers which are remoulded into our desire shape on heating and cooling are called thermoplastic.eg.PVC,Teflon
Those polymers which are not re mouded into our desire shape on heating and cooling are called thermoplastic.eg.Bakelite,Melamine.

Question. How is Dacron obtained?
Answer : Dacron is obtained by the condensation of ethylene glycol and terephthalic acid.

Question. Give the synthesis of a) Neoprene b) Teflon.
Answer : (a) n CH₂=C (cl) -CH=CH₂ -------(CH₂-C(cl) =CH-CH₂) n
(b) n(CF₂=CF₂) --------------(-CF₂-CF₂) n

Question. What do you mean by nylon-6,6?
Answer : Nylon6,6 is a condensation polymer and is made up of two different monomer units ie,hexamethylenediamine and adipic acid.

Three marks questions on polymer

Question. How does the presence of double bond in rubber molecule influence their structure and reactivity?
Answer : The natural rubber is a linear1,4-polyisoprene.Double bonds are located between C-2 and C-3 of isoprene units.This configuration about double bond do not allow the chains to come closer for effective attraction due to weak intermolecular forces of attraction.That is why natural rubber has a coiled structure and shows elasticity.

Question. Arrange the following polymers in increasing order of their nter molecular forces.
a) PVC,Naturalrubber,Terylene,
b) Nylon-6,6,Neoprene,PVC
c) Nylon6,Buna-N,Teflon
Answer : a) Natural rubber<PVC<Terylene
b) Neoprene<PVC<Nylon6,6
c) Buna-N<Teflon<nylon6

Question. Write the names of monomers used f0r getting the following polymers.
a) PVC
b) Teflon
c) bakelite
d) Neoprene
e) Polyacrylonitrile
f) Buna-S
Answer : a) Vinyl chloride b) Tetrafluoroethene c) Phenol and formaldehyde
d) 2-chloro 1,3-butadiene,e) Acrylonitrile,f) 1,3 Butadiene and styrene

Question. Classify the following as addition and condensation polymer:PHBV,Dacron,Teflon,neoprene,PVC,Bakelite
Answer : Addition polymer:Teflon,PVC,Neoprene
Condensation polymer:PHBV,Bakelite,Dacron

Question. Discuss and classify the polymers on the basis of inter molecular forces.
Answer : 1) Elastomer: Weakest intermolecular forces eg.Buna-N,Buna-S
2.Fibre; Strong intermolecular force like hydrogen bond eg Nylon-66
3. Thermoplastic;No cross linkage eg PVC
4. Thermosetting Polymer; numerous cross linkage egBakelite

Question. Arrange the following polymers in the increasing order of their intermolecular forces :
Terylene, Polythene, Neoprene.
Answer : Neoprene < Polythene < Terylene.

Question. What does the part ‘6,6’ mean in the name nylon-6, 6?
Answer : In nylon 6, 6, designation ‘6, 6’ mean that both the monomers hexamethylene diamine and adipic acid contain six carbon atoms each.

Question. Which of the following is a natural polymer?
Buna-S, Proteins, PVC
Answer : Proteins are natural polymers.

Question. Based on molecular forces what type of polymer is neoprene?
Answer : Elastomer.

Question. Which of the following is a fibre?
Nylon, Neoprene, PVC
Answer : Nylon is a fibre.

Question. Explain the following terms giving a suitable example for each:
(i) Condensation polymers
(ii) Addition polymers
Answer : Addition polymers : Th polymers formed by the addition reaction of a large number of unsaturated monomers are called addition polymers.
For example : Polythene, polystyrene.
Condensation polymers : Th polymers formed by the condensation of two or more bi functional monomers are called condensation polymers.
For example : Nylon 6,6, Bakelite.

Question. Mention two important uses of each of the following :
(i) Bakelite (ii) Nylon 6
Answer : (i) Bakellite is used for making combs, electrical switches, handles of various utensils and phonograph records.
(ii) Nylon–6 is used for making tyre cords, ropes and fabrics.

Question. Write the name of the monomers of the following polymers :
(i) Polythene (ii) Polyvinyl chloride
(iii) Bakelite
Answer : (i) Monomer of polythene is ethene.
(ii) Monomer of PVC is vinyl chloride.
(iii) Monomers of Bakelite are formaldehyde and Phenol.

Question. What is the difference between elastomers and fibres? Give one example of each.
Answer : (i) In elastomers polymer chains are held together by weakest intermolecular forces.
These have elastic properties. e.g. Buna-N, Buna-S.
(ii) In bres polymer chains are held together by strong intermolecular forces like hydrogen bonding.
These have high tensile strength.
e.g., Terylene, Nylon 6,6, etc.

1 MARK QUESTIONS

1. What are polymers?

2. What do you mean by the term polyamides?

3. Give examples of semisynthetic polymers?

4. What are copolymers?

5. What are elastomers?

6. What are biodegradable polymers?

7. Mention one use of Buna-S.

8. Name the monomers of natural rubber.

9. Name the polymer used for making unbreakable crockery.

10. Name the polymer which is used for making non- stick utensils.

2 MARKS QUESTIONS

11. What is meant by polymerization? What type of polymer is Teflon and what is its chief use?

12. Give the classification of polymers based on molecular forces.

13. Give the classification of polymers based on structure.

14. Arrange the following polymers in the increasing order of their intermolecular forces. Also classify them as addition and condensation polymers: Nylon-6 , Neoprene , PVC.

15. Why do the densities of low density polythene and high density polythene differ?

16. Could a copolymer be formed in both addition and condensation polymerization or not? Explain with examples.

17. What is vulcanization of rubber?

18. Give three differences between linear polymers and branched- chain.