Chapter 15

Class 12 Chemistry · 57 questions · 57 with answers

Questions

Q1Multiple choice

Which of the following polymers of glucose is stored by animals?

  • (i)Cellulose
  • (ii)Amylose
  • (iii)Amylopectin
  • (iv)Glycogen
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(iv) Glycogen

Q2Multiple choice

Which of the following is not a semisynthetic polymer?

  • (i)cis-polyisoprene
  • (ii)Cellulose nitrate
  • (iii)Cellulose acetate
  • (iv)Vulcanised rubber
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(i) cis-polyisoprene

Q3Multiple choice

The commercial name of polyacrylonitrile is ______________.

  • (i)Dacron
  • (ii)Orlon (acrilan)
  • (iii)PVC
  • (iv)Bakelite
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(ii) Orlon (acrilan)

Q4Multiple choice

Which of the following polymer is biodegradable?

  • (i)
  • (ii)
  • (iii)
  • (iv)
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(iv)

Q5Multiple choice

In which of the following polymers ethylene glycol is one of the monomer units?

  • (i)
  • (ii)
  • (iii)
  • (iv)
Show answer

(i)

Q6Multiple choice

Which of the following statements is not true about low density polythene?

  • (i)Tough
  • (ii)Hard
  • (iii)Poor conductor of electricity
  • (iv)Highly branched structure
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(iii) Poor conductor of electricity

Q7Multiple choice

is a polymer having monomer units ____________.

  • (i)
  • (ii)
  • (iii)
  • (iv)
Show answer

(i)

Q8Multiple choice

Which of the following polymer can be formed by using the following monomer unit?

  • (i)Nylon 6, 6
  • (ii)Nylon 2–nylon 6
  • (iii)Melamine polymer
  • (iv)Nylon-6
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(iv) Nylon-6

Q9Multiple correct

Which of the following polymers, need atleast one diene monomer for their preparation?

  • (i)Dacron
  • (ii)Buna-S
  • (iii)Neoprene
  • (iv)Novolac
Show answer

(ii) Buna-S

(iii) Neoprene

Q10Multiple correct

Which of the folloiwng are characteristics of thermosetting polymers?

  • (i)Heavily branched cross linked polymers.
  • (ii)Linear slightly branched long chain molecules.
  • (iii)Become infusible on moulding so cannot be reused.
  • (iv)Soften on heating and harden on cooling, can be reused.
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(i) Heavily branched cross linked polymers.

(iii) Become infusible on moulding so cannot be reused.

Q11Multiple correct

Which of the following polymers are thermoplastic?

  • (i)Teflon
  • (ii)Natural rubber
  • (iii)Neoprene
  • (iv)Polystyrene
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(i) Teflon

(iv) Polystyrene

Q12Multiple correct

Which of the following polymers are used as fibre?

  • (i)Polytetrafluoroethane
  • (ii)Polychloroprene
  • (iii)Nylon
  • (iv)Terylene 219 Polymers
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(iii) Nylon

(iv) Terylene 219 Polymers

Q13Multiple correct

Which of the following are addition polymers?

  • (i)Nylon
  • (ii)Melamine formaldehyde resin
  • (iii)Orlon
  • (iv)Polystyrene
Show answer

(iii) Orlon

(iv) Polystyrene

Q14Multiple correct

Which of the following polymers are condensation polymers?

  • (i)Bakelite
  • (ii)Teflon
  • (iii)Butyl rubber
  • (iv)Melamine formaldehyde resin
Show answer

(i) Bakelite

(iv) Melamine formaldehyde resin

Q15Multiple correct

Which of the following monomers form biodegradable polymers?

  • (i)3-hydroxybutanoic acid + 3-hydroxypentanoic acid
  • (ii)Glycine + amino caproic acid
  • (iii)Ethylene glycol + phthalic acid
  • (iv)Caprolactum
Show answer

(i) 3-hydroxybutanoic acid + 3-hydroxypentanoic acid

(ii) Glycine + amino caproic acid

Q16Multiple correct

Which of the following are example of synthetic rubber?

  • (i)Polychloroprene
  • (ii)Polyacrylonitrile
  • (iii)Buna-N
  • (iv)cis-polyisoprene
Show answer

(i) Polychloroprene

(iii) Buna-N

Q17Multiple correct

Which of the following polymers can have strong intermolecular forces?

  • (i)Nylon
  • (ii)Polystyrene
  • (iii)Rubber
  • (iv)Polyesters
Show answer

(i) Nylon

(iv) Polyesters

Q18Multiple correct

Which of the following polymers have vinylic monomer units?

  • (i)Acrilan
  • (ii)Polystyrene
  • (iii)Nylon
  • (iv)Teflon
Show answer

(i) Acrilan

(ii) Polystyrene

(iv) Teflon

Q19Multiple correct

Vulcanisation makes rubber ______________.

  • (i)more elastic
  • (ii)soluble in inorganic solvent
  • (iii)crystalline
  • (iv)more stiff
Show answer

(i) more elastic

(iv) more stiff

Q20Short answer

A natural linear polymer of 2-methyl-1, 3-butadiene becomes hard on treatment with sulphur between 373 to 415 K and —S—S— bonds are formed between chains. Write the structure of the product of this treatment?

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Vulcanised rubber. For structure see Class XII NCERT textbook.

Q21Short answer

Identify the type of polymer. —A—A—A—A—A—A—

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Homopolymer

Q22Short answer

Identify the type of polymer. —A—B—B—A—A—A—B—A—

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Copolymer

Q23Short answer

Out of chain growth polymerisation and step growth polymerisation, in which type will you place the following.

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Chain growth polymerisation

Q24Short answer

Identify the type of polymer given in the following figure.

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Cross-linked polymer

Q25Short answer

Identify the polymer given below :

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Polyisoprene/Natural rubber

Q26Short answer

Why are rubbers called elastomers?

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Rubbers are stretched on application of force and regain original state after the force is removed. Therefore these are called elastomers.

Q27Short answer

Can enzyme be called a polymer?

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Enzymes are biocatalysts which are proteins and are thus polymers.

Q28Short answer

Can nucleic acids, proteins and starch be considered as step growth polymers?

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[Hint : Yes, step growth polymers are condensation polymers and they are formed by the loss of simple molecule like water leading to the formation of high molecular mass polymers.]

Q29Short answer

How is the following resin intermediate prepared and which polymer is formed by this monomer unit?

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Melamine and formaldehyde are starting materials for this intermediate. Its polymerisation gives melamine polymer.

Q30Short answer

To have practical applications why are cross links required in rubber?

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Cross links bind the planar polymer sheets thus increasing its elastomeric properties.

Q31Short answer

Why does cis-polyisoprene possess elastic property? 221 Polymers

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See Class XII, NCERT text book, page no.434.

Q32Short answer

What is the structural difference between HDP and LDP? How does the structure account for different behaviour and nature, hence the use of a polymer?

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See Class-XII NCERT textbook, page no. 429-30.

Q33Short answer

What is the role of benzoyl peroxide in addition polymerisation of alkenes? Explain its mode of action with the help of an example.

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See Class-XII NCERT textbook, page no. 428.

Q34Short answer

Which factor imparts crystalline nature to a polymer like nylon?

Show answer

Strong intermolecular forces like hydrogen-bonding, lead to close packing of chains that imparts crystalline character.

Q35Short answer

Name the polymers used in laminated sheets and give the name of monomeric units involved in its formation.

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Urea formaldehyde resins. Monomer units are urea and formaldehyde.

Q36Short answer

Which type of biomolecules have some structural similarity with synthetic polyamides? What is this similarity?

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Proteins. Polyamides and proteins both contain amide linkage.

Q37Short answer

Why should the monomers used in addition polymerisation through free radical pathway be very pure?

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Pure monomers are required because even the traces of impurities may act like inhibitors which leads to the formation of polymers with shorter chain length. IV. Matching Type

Q38Multiple choice

Match the polymer of column I with correct monomer of column II. Column I Column II (i) High density polythene

  • (a)Isoprene (ii) Neoprene
  • (b)Tetrafluoroethene (iii) Natural rubber
  • (c)Chloroprene (iv) Teflon
  • (d)Acrylonitrile (v) Acrilan (e) Ethene
Show answer

(a) Isoprene (ii) Neoprene

(b) Tetrafluoroethene (iii) Natural rubber

(c) Chloroprene (iv) Teflon

(d) Acrylonitrile (v) Acrilan (e) Ethene

Q39Multiple choice

Match the polymers given in Column I with their chemical names given in Column II. Column I Column II (i) Nylon 6

  • (a)Polyvinyl chloride (ii) PVC
  • (b)Polyacrylonitrile (iii) Acrilan
  • (c)Polycaprolactum (iv) Natural rubber
  • (d)Low density polythene (v) LDP (e) cis-polyisoprene
Show answer

(a) Polyvinyl chloride (ii) PVC

(c) Polycaprolactum (iv) Natural rubber

(b) Polyacrylonitrile (iii) Acrilan

(d) Low density polythene (v) LDP (e) cis-polyisoprene

Q40Multiple choice

Match the polymers given in Column I with their commercial names given in Column II. Column I Column II (i) Polyester of glycol and phthalic acid

  • (a)Novolac (ii) Copolymer of 1, 3-butadiene and styrene
  • (b)Glyptal (iii) Phenol and formaldehyde resin
  • (c)Buna-S (iv) Polyester of glycol and terephthalic acid
  • (d)Buna-N (v) Copolymer of 1, 3-butadiene and acrylonitrile (e) Dacron
Show answer

(a) Novolac (ii) Copolymer of 1, 3-butadiene and styrene

(b) Glyptal (iii) Phenol and formaldehyde resin

(c) Buna-S (iv) Polyester of glycol and terephthalic acid

(d) Buna-N (v) Copolymer of 1, 3-butadiene and acrylonitrile (e) Dacron

Q41Multiple choice

Match the polymers given in Column I with their main applications given in Column II. Column I Column II (i) Bakelite

  • (a)Unbreakable crockery (ii) Low density polythene
  • (b)Non-stick cookwares (iii) Melamine-formaldehyde resin
  • (c)Packaging material for shock absorbance (iv) Nylon 6
  • (d)Electrical switches (v) Polytetrafluoroethane (e) Squeeze bottles (vi) Polystyrene (f) Tyre, cords
Show answer

(a) Unbreakable crockery (ii) Low density polythene

(d) Electrical switches (v) Polytetrafluoroethane (e) Squeeze bottles (vi) Polystyrene (f) Tyre, cords

(b) Non-stick cookwares (iii) Melamine-formaldehyde resin

(c) Packaging material for shock absorbance (iv) Nylon 6

Q42Multiple choice

Match the polymers given in Column I with the preferred mode of polymerisation followed by their monomers. Column I Column II (i) Nylon-6,6

  • (a)Free radical polymerisation (ii) PVC
  • (b)Ziegler-Natta polymerisation or coordination polymerisation (iii) HDP
  • (c)Anionic polymerisation
  • (d)Condensation polymerisation
Show answer

(a) Free radical polymerisation (ii) PVC

(d) Condensation polymerisation

(b) Ziegler-Natta polymerisation or coordination polymerisation (iii) HDP

(c) Anionic polymerisation

Q43Multiple choice

Match the polymers given in Column I with the type of linkage present in them given in Column II. Column I Column II (i) Terylene

  • (a)Glycosidic linkage (ii) Nylon
  • (b)Ester linkage (iii) Cellulose
  • (c)Phosphodiester linkage (iv) Protein
  • (d)Amide linkage (v) RNA
Show answer

(a) Glycosidic linkage (ii) Nylon

(b) Ester linkage (iii) Cellulose

(d) Amide linkage (v) RNA

(c) Phosphodiester linkage (iv) Protein

Q44Multiple choice

Match materials given in Column I with the polymers given in Column II. Column I Column II (i) Natural rubber latex

  • (a)Nylon (ii) Wood laminates
  • (b)Neoprene (iii) Ropes and fibres
  • (c)Dacron (iv) Polyester fabric
  • (d)Melamine formaldehyde resins (v) Synthetic rubber (e) Urea-formaldehyde resins (vi) Unbreakable crockery (f) cis-polyisoprene 223 Polymers
Show answer

(a) Nylon (ii) Wood laminates

(b) Neoprene (iii) Ropes and fibres

(c) Dacron (iv) Polyester fabric

(d) Melamine formaldehyde resins (v) Synthetic rubber (e) Urea-formaldehyde resins (vi) Unbreakable crockery (f) cis-polyisoprene 223 Polymers

Q45Multiple choice

Match the polymers given in Column I with their repeating units given in Column II. Column I Column II (i) Acrilan

  • (a)(ii) Polystyrene
  • (b)(iii) Neoprene
  • (c)(iv) Novolac
  • (d)(v) Buna—N (e) (f)
Show answer

(a) (ii) Polystyrene

(d) (v) Buna—N (e) (f)

(b) (iii) Neoprene

(c) (iv) Novolac

Q46Assertion & reason

Assertion (A): Rayon is a semi synthetic polymer and is taken as a better choice than cotton fabric.

Reason (R): Mechanical and aesthetic properties of cellulose can be improved by acetylation.

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Q47Assertion & reason

Assertion (A): Most of the Synthetic polymers are not biodegradable.

Reason (R): Polymerisation process induces toxic character in organic molecules.

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Q48Assertion & reason

Assertion (A): Olefinic monomers undergo addition polymerisation.

Reason (R): Polymerisation of vinylchloride is initiated by peroxides/ persulphates.

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Q49Assertion & reason

Assertion (A): Polyamides are best used as fibres because of high tensile strength.

Reason (R): Strong intermolecular forces (like hydrogen bonding within polyamides) lead to close packing of chains and increase the crystalline character, hence, provide high tensile strength to polymers.

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Q50Assertion & reason

Assertion (A): For making rubber synthetically, isoprene molecules are polymerised.

Reason (R): Neoprene (a polymer of chloroprene) is a synthetic rubber.

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(v)

Q51Assertion & reason

Assertion (A): Network polymers are thermosetting.

Reason (R): Network polymers have high molecular mass.

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Q52Assertion & reason

Assertion (A): Polytetrafluoroethene is used in making non-stick cookwares.

Reason (R): Fluorine has highest electronegativity.

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Q53Long answer

Synthetic polymers do not degrade in the environment for a long time. How can biodegradable synthetic polymers be made. Differentiate between biopolymers and biodegradable polymers and give examples of each type.

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See NCERT textbook for Class XII.

Q54Long answer

Differentiate between rubbers and plastics on the basis of intermolecular forces.

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See NCERT textbook for Class XII.

Q55Multiple choice

Phenol and formaldehyde undergo condensation to give a polymar

  • (A)which on heating with formaldehyde gives a thermosetting polymer
  • (B). Name the polymers. Write the reactions involved in the formation of (A). What is the structural difference between two polymers?
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(A) which on heating with formaldehyde gives a thermosetting polymer

(B) . Name the polymers. Write the reactions involved in the formation of (A). What is the structural difference between two polymers?

Q56Long answer

Low density polythene and high density polythene, both are polymers of ethene but there is marked difference in their properties. Explain.

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Hint : Low density and high density polythenes are obtained under different conditions. These differ in their structural features. Low density polythenes are highly branched structures while high density polythene consists of closely packed linear molecules. Close packing increases the density.

Q57Long answer

Which of the following polymers soften on heating and harden on cooling? What are the polymers with this property collectively called? What are the structural similarities between such polymers? Bakelite, urea-formaldehyde resin, polythene, polyvinyls, polystyrene. 225 Polymers

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Hint : Polythene, polyvinyls and polystyrene soften on heating and harden on cooling. Such polymers are called thermoplastic polymers. These polymers are linear or slightly branched long chain molecules. These possess intermolecular forces whose strength lies between strength of intermolecular forces of elastomers and fibres. 227 Polymers