Tag: man made materials

Quizzes (8) Questions (131)

Questions Related to man made materials

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

Synthetic fibers are obtained from which of the following?

  1. Plants

  2. Sheeps

  3. Chemicals

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

Synthetic fibres are created by extruding fibre forming materials through spinnerets into air and water, forming a thread. These artificially manufactured fibres were made from polymers obtained from petro chemicals. These fibres are called synthetic or artificial fibres. The two most common ones are nylon and polyester. Nylon is made from two chemicals, adipic acid (AA) and hexamethylene diamine (HMD).

Therefore, the correct answer is option C.

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

Which of the following is considered the first thermoplastic?

  1. PVC

  2. Polystyrene

  3. Melamine

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

Celluloid, which is considered the first thermoplastic, made its appearance in the mid- 1800 s and reigned in the industry for approximately 100 years. During its peak production, it was used as a substitute for ivory. Today, it is used to make guitar picks.

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

Which of the following is a thermosetting process?

  1. Vulcanization of rubber

  2. Polythene extrusion

  3. Injection molding of PVC

  4. None of above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Vulcanization is a chemical process for converting natural rubber or related polymers into more durable materials via the addition of sulphur or other equivalent curatives or accelerators. Cross-linking introduced by vulcanization prevents the polymer chains from moving independently. As a result, when stress is applied the vulcanized rubber deforms, but upon release of the stress it reverts to its original shape.

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

State true or false.


Nylon is a thermosetting plastic.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
Thermoplastics are the polymers which loses their shape on heating and regain their shape on cooling.
Examples: Nylon, PVC, polystyrene, etc.
On the opposite of that Thermosetting doesn't regain its shape after heating.
Nylon is a thermoplastic polymer. Hence the given statement is false.
Multiple choice chemistry man made materials environmental impact: plastics plastic plastic plastic waste garbage in, garbage out

Which among the following is a poor conductor of heat and electricity?

  1. Melamine

  2. Bakelite

  3. Both A and B

  4. None of above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Bakelite is a thermosetting plastic which is one of the first plastic made from synthetic components. Bakelite was used for its electrical non-conductivity and heat-resistant properties in electrical insulators, radio, and telephone casings.

Similarly, Melamine resin is a thermosetting plastic used in high pressure decorative laminates, laminate floorings and dry erase boards.

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

Define plasticity :

  1. Ability to regain its original shape.

  2. Ability to flow when subjected to stress.

  3. Ability to change shape permanently.

  4. Both b and c.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Plasticity,  ability of certain solids to flow or to change shape permanently when subjected to stresses of intermediate magnitude between those producing temporary deformation, or elastic behaviour, and those causing failure of the material, or rupture.

 Plasticity enables a solid under the action of external forces to undergo permanent deformation without rupture.