Chemistry

Polymers and Plastics

1,227 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 chemistry composition of matter heterogeneous mixture - suspension and its properties suspension types of mixture

Powder coating is a process which requires a solvent to keep the binder and filler parts in a liquid suspension form.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The main difference between a conventional liquid paint and a powder coating is that the powder coating does not require a solvent to keep the binder and filler parts in a liquid suspension form while liquid paints require.

Multiple choice

which of the following correctly describes biodegradable plastics

  1. some plastics deteriorate when exposed to sunlight

  2. plastic that contain sugar can be broken down by bacteria

  3. degradable plastics usually bread down smaller pieces

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Biodegradable plastics encompass multiple types: photodegradable (break down in sunlight), biodegradable (sugar-based plastics broken down by microbes), and degradable plastics that fragment into smaller pieces. 'All of the above' correctly captures the variety of technologies.

Multiple choice chemistry animal fibre synthetic fibres & their characteristics processing of fibres synthetic fibres and its types

Which of the following is not a natural polymer?

  1. Starch

  2. Nucleic acid

  3. Polystyrene

  4. Protein
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Polystyrene is made of styrene monomer which is a synthetic polymer. The monomer is a liquid petrochemical.

Polystyrene are used in making CD, jewel cases, expanded polystyrene (EPS) Foam products from Foam cups to Foam coolers, etc.

Multiple choice chemistry animal fibre synthetic fibres & their characteristics processing of fibres synthetic fibres and its types

The naturally occurring polymer among the following is:

  1. Rayon
  2. Nylon - $6$

  3. Decron

  4. Proteins
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

NATURAL  POLYMER  -  The polymers found in nature, i.e., from plants & animals are known as natural polymers.
RAYON - Rayon is classified as semisynthetic polymer, as it is manufactured from naturally occuring polymers. It is purified from cellulose.
NYLON - $6$  -  Nylon - $6$ is a synthetic polymer, obtained by heating caprolactum with water at high temp.
DACRON  -  It is also a synthetic polymer. It is formed by interaction of ethylene glycol & terephthalic acid.
PROTEINS  -  Proteins are large macromolecules, containing one or more chains of amino acids. They are held together by peptide bonds. Amino acids are found in living organisms. Hence, they are natural polymer.

Multiple choice chemistry animal fibre synthetic fibres & their characteristics processing of fibres synthetic fibres and its types

The acrylic polymer must contain :

  1. acrylonitrile monomer.

  2. sodium thiocyanate.

  3. acrylic acid.

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

Acrylic fibers are synthetic fibers made from a polymer (polyacrylonitrile) with an average molecular weight of approx 100,000, about 1900 monomer units. 


For a fiber to be called acrylic, the polymer must contain at least 85% acrylonitrile monomer. Acrylonitrile is an organic compound that is a colorless volatile liquid.

So, the correct option is $A$

Multiple choice chemistry animal fibre synthetic fibres & their characteristics processing of fibres synthetic fibres and its types

State True or False.


Teflon is natural polymer.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

There are two types of polymers: synthetic and natural. 


Synthetic polymers are derived from petroleum oil and made by scientists and engineers. Examples of synthetic polymers include nylon, polyethene, polyester, Teflon, and epoxy. 

Natural polymers occur in nature and can be extracted. They are often water-based. Examples of naturally occurring polymers are silk, natural rubber, wool, DNA, cellulose and proteins.

Hence, it is a false statement.

Multiple choice chemistry animal fibre synthetic fibres & their characteristics processing of fibres synthetic fibres and its types

Which of the following is not a synthetic polymer?

  1. polyvinyl chloride

  2. plastic

  3. polystyrene

  4. polyethylene

  5. cellulose
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

Cellulose is not a synthetic polymer. It is a natural polymer.
It is a polysacchardie having molecular formula $(C _6H _{10}O _5) _n$. It has linear chain of $\beta(1\rightarrow 4)$ linked D-glucose units. There are several hundred to many thousands of such units in a chain.  Cellulose is an important structural component of  in the primary cell wall of green plants, many forms of algae and the oomycetes.

Multiple choice

What is the repeating structural unit of a polymer called?

  1. Monomer

  2. Polymer

  3. Oligomer

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

A monomer is the basic unit that repeats to form a polymer.

Multiple choice

Which type of polymerization involves the formation of a carbon-carbon bond between monomers?

  1. Addition polymerization

  2. Condensation polymerization

  3. Free radical polymerization

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

Addition polymerization involves the formation of a carbon-carbon bond between monomers.

Multiple choice

What is the term used to describe the average molecular weight of a polymer?

  1. Molecular weight

  2. Number-average molecular weight

  3. Weight-average molecular weight

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

Number-average molecular weight is the average molecular weight calculated by dividing the total molecular weight of all molecules in a sample by the number of molecules.

Multiple choice

Which property of polymers is responsible for their ability to stretch and return to their original shape?

  1. Tensile strength

  2. Elongation at break

  3. Young's modulus

  4. Resilience
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Resilience is the property of polymers that allows them to absorb energy upon deformation and return to their original shape when the stress is removed.

Multiple choice

What is the term used to describe the glass transition temperature of a polymer?

  1. Melting point

  2. Boiling point

  3. Glass transition temperature

  4. Decomposition temperature
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Glass transition temperature is the temperature at which a polymer changes from a glassy state to a rubbery state.