Tag: environmental impact: plastics

Questions Related to environmental impact: plastics

Multiple choice chemistry man made materials environmental impact: plastics plastic plastic plastic waste garbage in, garbage out

Nylon is obtained by:

  1. treating wood pulp

  2. solidifying water

  3. mixing coal, air and water

  4. mixing chemicals

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

Nylon was first commercially synthesized fibre. The production of nylon was started almost simultaneously in New York and London, thus it got its name (NY for New York and Lon for London) as nylon. Nylon is synthesized from coal, water and air. Fibre of nylon is very strong and it also resembles silk.

Multiple choice chemistry man made materials environmental impact: plastics plastic plastic plastic waste garbage in, garbage out

Bakelite is an example of ___.

  1. elastomer

  2. fibre

  3. thermoplastic

  4. thermosetting polymer

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

A thermosetting plastic, also known as a thermoset, is a polymer material that irreversibly cures. The cure may be induced by heat, generally above $200^o C$ $(392\ F)$, through a chemical reaction or a suitable irradiation.
$Bakelite$ is one example of this type.

Multiple choice chemistry man made materials environmental impact: plastics plastic plastic plastic waste garbage in, garbage out

Polystyrene and PVC are thermoplastics.

  1. True

  2. False

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

Polymer of styrene and vinyl chloride (polystyrene and PVC)  can be repeatedly melted and re-molded into new products and are 100% recyclable


Therefore they are examples of thermoplastic. Other examples of thermoplastics include polythene (PE), polypropylene (PP), nylons, etc.

Therefore, option A is correct.

Multiple choice chemistry man made materials environmental impact: plastics plastic plastic plastic waste garbage in, garbage out

Consider the following statements-


I. weakest intermolecular forces are present in elastomers.

II. Fibers possess a crystalline nature.


III. Ionic bonds are present in thermoplastic polymers.

Select the correct option from the following:
  1. I and II

  2. II and III

  3. I and III

  4. I,II and III

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
Elastomers are rubber like solid polymers in which polymer chains are hold together by weakest intermolecular forces.
Eg : Natural rubber
Fibers are thread-like polymers & can be woven into fabrics. They possess high tensile strength & are crystalline in nature.
Eg ; Nylon $6,6$.

Hence, the correct option is A.
Multiple choice chemistry man made materials environmental impact: plastics plastic plastic plastic waste garbage in, garbage out

Thermosetting plastics cannot be softened by heating because:

  1. they are cross linked polymers with hydrogen bonds b/w each other.

  2. they are linear chains of polymers

  3. they are large cross-linked molecules with strong covalent bonds b/w the atoms along each chains

  4. they are large cross-linked molecules with strong electrovalent bonds between the atom along each chain.

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

Thermosetting polymers are formed from monomers of viscous state which changes irreversibly on heating into an infusible insoluble polymer. They have high crosslinks due to which they are rigid.

Multiple choice chemistry man made materials environmental impact: plastics plastic plastic plastic waste garbage in, garbage out

Which of the following properties of plastic make it most convenient to use?

  1. It is non-reactive

  2. Light, strong and durable

  3. Easily remouldable

  4. All of the above

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

Plastics are non-reactive at room temperature and others are highly reactive.

Because of lower density than metals, plastic is light, strong and durable so can be molded in different shapes and sizes easily.
So all the options are correct, all are properties of plastic.

Option D is correct answer.

Multiple choice chemistry man made materials environmental impact: plastics plastic plastic plastic waste garbage in, garbage out

Which one among the following is a thermosetting plastic?

  1. PVC

  2. PVA

  3. Bakelite

  4. Perspex

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
Bakelite is another name of phenol formaldehyde which is a thermosetting plastic so bakelite is a thermosetting plastic.

Plastic which has cross-linked (3D) structure and is generally made by the condensation polymerization method is called thermosetting plastic. It can't be reused once it is processed.

Multiple choice chemistry man made materials environmental impact: plastics plastic plastic plastic waste garbage in, garbage out

Which of the following is not correct regarding terylene ?

  1. Condensation polymer

  2. Synthetic fibre

  3. Step-growth polymer

  4. Known as dacron

  5. Thermosetting plastic

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

Terylene is a synthetic polymer formed by the condensation polymerization reaction of terephthalic acid and ethylene glycol with the release of a methanol molecule. 


It forms by a step-growth polymerization mechanism in which a bi-functional or multifunctional monomer react to form the first dimer, then trimer, longer oligomer and eventually long-chain polymers. 

It is also called as Dacron and is a thermoplastic, which can be remelted time and again without producing any change.