Engineering Chemistry MCQ (Polymer Classification)

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Engineering Chemistry MCQ (Polymer Classification)

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Polymer Classification

1. A polymer is any substance made up of many repeating units called ______________
a) Resins
b) Plastic
c) Mers
d) Blocks
Answer: c
Explanation: A polymer is any substance made up of many repeating units, building
blocks called mers. Polymers are made up of many many molecules all strung
together to form really long chains.

2. Small molecules which combine to form polymer are called ____________
a) Resins
b) Monomers
c) Plastic
d) Blocks
Answer: b
Explanation: Small molecules which combine with each other to form polymer are
called monomers. Polymers are made up of many many molecules all strung together to form really long chains

3. Select the incorrect statement from the following options.
a) When in form ready for further working, polymers are called resins
b) The chemical process leading to the formation of polymer is known as polymerisation
c) The number of monomeric units contained in the polymer is called the degree of polymerisation
d) Due to their small size, polymers are also called micro-molecules
Answer: d
Explanation: Due to their large size, polymers are also called macro-molecules. All
the other options are correct. When in form ready for further working, polymers are
called resins. The chemical process leading to the formation of polymer is known as
polymerisation and the number of monomeric units contained in polymer is called degree of polymerisation.

4. Below threshold degree of polymerisation (DP), the polymer does not possess any strength and exist either as liquid resin or friable powder.
a) True
b) False
Answer: a
Explanation: Below threshold degree of polymerisation, the polymer does not
possess any strength and exist either as liquid resin or friable powder. The number
of monomeric units contained in the polymer is called degree of polymerisation.

5. The optimum DP value of cellulose is ____________
a) 150
b) 250
c) 400
d) 500
Answer: b
Explanation: The optimum DP value of cellulose is 250. The number of monomeric
units contained in the polymer is called degree of polymerisation (DP).

6. The functionality of ethylene glycol is ____________
a) 2
b) 3
c) 4
d) 5
Answer: a
Explanation: The functionality of ethylene glycol is 2. It is a colorless, odorless,
viscous dihydroxy alcohol and has a sweet taste, but is poisonous if ingested.

7. Which of the following polymer is not classified under the category of configuration?
a) Syndiotactic
b) Atactic
c) Cross-linked
d) Isotactic
Answer: c
Explanation: Cross-linked polymer is not classified under the category of
configuration. Syndiotactic, atactic and isotactic are classified under the category of
configuration. Tacticity is the relative stereochemistry of adjacent chiral centers within a macromolecule.

8. Which of the following is not an example of semi-crystalline polymer?
a) HDPE
b) Nylon
c) Polyesters
d) LDPE
Answer: d
Explanation: LDPE is not an example of a semi-crystalline polymer. It is an example
of a branched amorphous polymer. All the other options are examples of semicrystalline polymer.

9. Styrene acrylonitrile is an example of ____________
a) Co-polymer
b) Homopolymer
c) Linear polymer
d) Amorphous polymer
Answer: a
Explanation: Styrene acrylonitrile resin is a copolymer plastic consisting of styrene
and acrylonitrile. It is also known as SAN. It is widely used in place of polystyrene.

10. Which of the following polymer is not classified under the category of end use?
a) Fibers
b) Adhesives
c) Elastomers
d) Synthetic
Answer: d
Explanation: Synthetic polymer is not classified under the category of end use. It is
classified under the category of origin. Fibers, adhesives and elastomers are
classified under the category of end use.

11. Select the incorrect statement from the following option.
a) Thermosets are formed by condensation polymerisation reactions
b) Thermosets have 3-D, cross-linked network structure
c) Thermosets soften on heating and stiffen on cooling
d) Thermosets are generally insoluble in any solvent
Answer: c
Explanation: Thermosets do not soften on heating. All the other options are correct.
Thermosets are formed by condensation polymerisation reactions, have 3-D, crosslinked network structure and are generally insoluble in any solvent.

12. Which one of the following is not an example of thermoplastic?
a) Polyvinyl chloride
b) Nylon
c) Polyesters
d) Epoxy
Answer: d
Explanation: Epoxy is not an example of thermoplastic. It is an example of a
thermoset polymer. Polyvinyl chloride, nylon and polyesters are examples of thermoplastic.

13. The weight average molecular weight for PP given its degree of polymerisation as 10,000 will be ____________
a) 3,00,000 gm/mol
b) 4,20,000 gm/mol
c) 6,70,000 gm/mol
d) 8,40,000 gm/mol
Answer: b
Explanation: The weight average molecular weight for PP given its degree of
polymerisation as 10,000 will be 4,20,000 gm/mol.

14. The cryoscopy refers to ____________
a) Osmotic pressure measurement
b) Elevation in boiling point measurement
c) Freezing point depression measurement
d) Increase in solubility measurement
Answer: c
Explanation: The cryoscopy refers to freezing point depression measurement. A
technique for determining the molar concentration of a solution by measuring the freezing point.

15. Higher molecular weight polymers are tougher and more heat resistant.
a) True
b) False
Answer: a
Explanation: Higher molecular weight polymers are tougher and more heat
resistant. Polymeric mixtures are far less miscible than mixtures of small molecule materials.