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

Why is plastic used in covering of electrical appliances?

  1. Good conductors of heat and electricity

  2. Durable

  3. Poor conductors of heat and electricity

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

Plastic is a poor conductor of heat and electricity. 


This makes it suitable to make the covering of electric wires, handles of electrical appliances, handles of utensils, kitchenware, floor tiles, etc.

Hence the correct option is C.

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

The world's first fully synthetic plastic was:

  1. Polystyrene

  2. Nylon

  3. Bakelite

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

The world's first fully synthetic plastic was bakelite, invented in New York in 1907 by Leo Baekeland who coined the term 'plastics'. Bakelite is made from carbolic acid (phenol) and formaldehyde and is referred to as a phenolic resin. Bakelite was the first thermosetting plastic.


Hence, the correct option is $C$

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

Which of the following are the advantages of plastic over metals?
1. Plastics are lighter.
2. Plastics are usually cheaper.
3. Plastics are inert to both acids and alkalis.

  1. (1) and (2) only

  2. (1) and (3) only

  3. (2) and (3) only

  4. (1) ,(2) and (3)
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
With the increased knowledge of plastics and the improved capabilities of machining equipment, the industry is now capable of producing plastic components to the same exacting standards as metallic components.
Plastics can  provide the benefit of reduced weight. This is crucial for a manufacturer of aircraft parts, for instance, decreased weight means increased fuel efficiency. This has lead to manufacturers transitioning from aluminum and steel to plastic and composites.
Plastic are less sensitive to weather than metal, resisting corrosion and rust. In addition, additives can be introduced to protect the pieces from damaging UV rays.
Plastics are resistance to many more chemical compounds like acids and alkalis. This opens up the options for use in solution tanks.
Plastics can be designed for resist impact and dents, making it durable, strong, and stable.
Plastics have tighter tolerances.
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.