Tag: environmental impact: plastics

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Questions Related to environmental impact: plastics

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

Match the column A and B

Column A Column B
(i) Thermoplastics (a) Handles of utensils, floor tiles
(ii) Thermosetting plastics (b) Melamine
(iii) Biodegradable (c) Teflon
(iv) Fire proof plastic (d) Wood
(v) Oil and water do not stick (e) Combs, containers

  1. i-d, ii-e, iii-a, iv-b, v-c

  2. i-e, ii-a, iii-d, iv-b, v-c

  3. i-a, ii-d, iii-b, iv-c, v-e

  4. i-c, ii-b, iii-a, iv-e, v-d
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
Thermoplastic materials are those materials that are made of polymers linked by intermolecular interactions or van der Waals forces, forming linear or branched structures.

Melamine is a versatile material. It resists fire and can tolerate heat better than other plastics. It is used for making fire-resistive uniforms, floor tiles, kitchenware and fabrics which resist fire. 

Thermosetting plastics are generally strong and resistant to heat, but they melt the first time they are heated to a high enough temperature and harden (set) permanently when cooled. They can never be melted or reshaped again. 

They are used in situations where resistance to heat is important, e.g. on kitchen work surfaces, good-quality plastic cups, saucepan handles and plug casings. Wood is biodegradable

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

Thermoplastics are:

  1. linear polymers.

  2. soften or melt on heating

  3. molten polymer can be moulded in desired shape.

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

Thermoplastics are linear polymers. They are also known as thermosoftening plastics because they become malleable when heated. Although they are pliable above a certain heat threshold, they return to a solid once they have been sufficiently cooled. For this reason, thermoplastics are put to unique uses in a number of manufacturing and engineering industries.

Apart from their primary characteristics, thermoplastics vary slightly in usage and properties. For example, polystyrene is a hard, water-resistant thermoplastic, according to BBC. This makes it an excellent choice for creating toy models and for packaging that will not be exposed to extreme heat sources in transit. Polymethyl methacrylate is also a stiff thermoplastic, but it is also an electrical insulator and can be polished well, so it is often used in vehicle windows and light covers.

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

Which of the following is used to make disposable cups?

  1. Low density polyethylene

  2. Polypropylene

  3. Polystyrene

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

Disposable cups are made up of thermocol. It is a synthetic petroleum product which is made by restructuring of the chemical bonding of the polystyrene, to develop a stretch polystyrene. In this process, thermoplastic granules are expanded through the application of steam and air. The expanded granules become large and light in weight.

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

Thermosetting plastics can be remoulded on gentle heating.

  1. True

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

Thermosetting plastics: Which on heating becomes infusible these cannot be reused.Ex- Bakelite,urea formaldehyde resin.

Thermoplastic plastics: These become soft on heating and hard on cooling.
Ex.polythere,polystyrene.
Thermoplastic plastics can be remoulded.

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.