Chemistry

Polymers and Plastics

1,228 Questions

Polymers and plastics questions explore the properties, synthesis, and applications of various synthetic and natural polymers. Key topics include biodegradable plastics, vulcanization, and polymer nanocomposites. These concepts are frequently tested in science and engineering competitive exams.

Biodegradable plasticsPolymer nanocompositesVulcanization of rubberPolymer molecular weightAsphalt binders

Polymers and Plastics Questions

Multiple choice

The smallest repeating unit for the formation of large polymers is known as_______

  1. Monomer

  2. Repeating unit

  3. Polythene

  4. Dimer
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Monomers are the smallest repeating units that join together through polymerization to form large polymer chains. For example, ethene monomers join to form polythene. 'Repeating unit' refers to the unit within the polymer chain, not the starting molecule, and 'dimer' means only two units bonded together.

Multiple choice

Which of the following is a fire proof plastic?

  1. Teflon

  2. Melamine

  3. Polythene

  4. Polystyrene
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Melamine is a thermosetting plastic that exhibits excellent fire resistance due to its strong cross-linked molecular structure. Teflon (PTFE) has high heat resistance but is not specifically classified as fireproof, while polythene and polystyrene are thermoplastics that can melt and burn.

Multiple choice

Which property of melamine plastics enables them to make fire men uniform?

  1. Bad conductor of heat

  2. High tensile strength

  3. Resistance to fire

  4. Light weight and durability
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Melamine plastic is used in firefighter uniforms specifically because of its fire resistance property. It does not burn easily and can withstand high temperatures. While melamine is lightweight and has good tensile strength, the critical property for fire safety applications is its resistance to catching fire.

Multiple choice

The monomer used for the formation of polythene is_______

  1. Propene

  2. Ethene

  3. Ethyne

  4. Ethane
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Polythene (polyethylene) is formed by the polymerization of ethene (ethylene) monomers. When ethene molecules undergo addition polymerization, they link together to form the long chains that make up polythene. Propene would give polypropylene, ethyne is a different alkyne, and ethane is a saturated hydrocarbon.

Multiple choice

Nylon is formed by the condensation of

  1. adipic acid and hexamethylene diamine

  2. formaldehyde and phenol

  3. formaldehyde and styrene

  4. acrylonitrile

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Nylon-6,6 is synthesized through condensation polymerization of adipic acid (a dicarboxylic acid) and hexamethylene diamine (a diamine). Formaldehyde and phenol produce bakelite, while acrylonitrile is used for acrylic fibres. The correct monomers for nylon specifically are adipic acid and hexamethylene diamine.

Multiple choice

Match the following materials with its property?

 
(1) Nylon
(ii) Resists fire
(2) Polyester
(ii) Poor conductors of heat and electricity
(3) Melamine
(iii) Strong
(4) Bakelite
(iv) Insulator

  1. (1)-(iii), (2)-(iv), (3)-(i), (4)-(ii)

  2. (1)-(iv), (2)-(iii), (3)-(ii), (4)-(i)

  3. (1)-(ii), (2)-(i), (3)-(iii), (4)-(iv)

  4. (1)-(i), (2)-(ii), (3)-(iii), (4)-(iv)
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Nylon is a strong fibre, polyester prevents loss of body heat during winters. Melamine resists fire and bakelite is a poor conductor of heat and electricity.

Multiple choice

What is terylene?

  1. A thermosetting plastic

  2. A material used to make uniforms of firemen

  3. A popular polyester

  4. A material used in non-stick cookware

  5. A material known as artificial silk
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Terylene is a popular polyester.

Multiple choice

Which plant product is used to make biodegradable plastic?

  1. Cassava

  2. Wheat

  3. Coffee

  4. Sugarcane
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Cassava is a plant product used to make biodegradable plastic. Tapioca is a starch extracted from cassava.  In India, the term tapioca is used to represent the root of the plant (cassava), rather than the starch. Tapioca root can also be used to manufacture biodegradable plastic bags. 

Multiple choice

The breakdown of polymer into monomer is known as

  1. hydrolysis

  2. dissociation

  3. condensation

  4. elimination
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Hydrolysis is a chemical reaction in which molecules of water (H2O) are split into hydrogen cations (H+, identical to protons) and hydroxide anions (OH−) in the process of a chemical mechanism. It is the type of reaction, which is used to break down certain polymers, especially those made by condensation polymerization.