Tag: chemistry

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Multiple choice chemistry petrochemicals and polymers addition polymerisation types of polymerisation reactions polymer

Which of the following is added to improve flexibility of PVC?

  1. Rubber

  2. Plasticizers

  3. Ethane

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

With some additives in PVC, the physical and mechanical properties are improved.

Different additives such as plasticizers, fillers, stabilizer, pigments were mixed. These are added in order to increase the elongation i.e; its flexibility.

Multiple choice chemistry petrochemicals and polymers addition polymerisation types of polymerisation reactions polymer

Which is used in making various types of pipes?

  1. PVR

  2. PVC

  3. Bakelite

  4. Melamine
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
PVC (polyvinyl chloride) is used in making various types of pipes.
Note: PVC thermoplastic polymer. Its properties are between elastomers and fibers. On heating, it becomes soft and on cooling, become hard. It can be remoulded and recycled.
Multiple choice chemistry petrochemicals and polymers addition polymerisation types of polymerisation reactions polymer

PVC is an example of which kind of plastic?

  1. Thermoplastic

  2. Thermosetting

  3. It is not a type of plastic
  4. Both $A$ and $B$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

PVC (polyvinyl chloride) is thermoplastic polymer. Its properties are between elastomers and fibers. On heating, it becomes soft and on cooling, become hard. It can be remoulded and recycled.

Multiple choice chemistry petrochemicals and polymers addition polymerisation types of polymerisation reactions polymer

Which of the following polymer has the tendency of decomposing before melting ?

  1. Polystyrene

  2. PVC

  3. Nylon

  4. None of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
Thermosetting polymers such as Bakelite have the tendency of decomposing before melting. Thermoplastic polymers (such as PVC (polyvinyl chloride), polystyrene ) on heating, becomes soft and on cooling, become hard. They can be remolded and recycled. Their properties are between elastomers and fibers.
There is no thermosetting given in the option, all are thermoplastic.
Hence, the correct option is D.
Multiple choice chemistry petrochemicals and polymers addition polymerisation types of polymerisation reactions polymer

In condensation of polymerization, involves monomers which contain functional groups of:

  1. same kind

  2. different kind

  3. all groups

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

Condensation polymers involves monomers which join together losing a small molecules as byproducts such as $H _2O$, methanol, etc.

Condensation polymers are formed from two or more different monomers.

Multiple choice chemistry petrochemicals and polymers addition polymerisation types of polymerisation reactions polymer

Polymer formation from monomers starts by:

  1. condensation reaction between monomers

  2. coordination reaction between monomers

  3. conversion of monomers to monomer ion by protons

  4. hydrolysis of monomers
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Polymer formation from monomers starts by condensation reaction between monomers by removal of small molecules.