Thermosetting Plastics

Q.

Is PVC thermoplastic or thermosetting plastic?

Q. Which one among the following is a thermosetting plastic?

1. PVC
2. PVA
3. Bakelite
4. Perspex

Q.

Why all polymers are macromolecules but all macromolecules are not polymers.

Q.

Question 7 (b)
Explain why the following are made of thermosetting plastics.

Electric plugs/switches/plug boards.

Q.

The plastic which is coated on the uniforms of fireman to make them fire -resistant is :

(a) bakelite (b) polythene (c) teflon (d) melamine

Q.

Why are electric switches, plugs and sockets made of thermosetting plastics ?

Q.

Explain why, thermoplastics become soft on heating but thermosetting plastics do niot become soft on heating. Draw labelled diagrams to illustrate your answer.

Q.

Explain why, frying pan handles are made of thermosetting plastics.

Q.

Question 7 (a)
Explain why the following are made of thermosetting plastics.

Saucepan handles.

Q.

Are polythene and PVC examples of thermosetting plastic?

Q.

Is polythene a thermosetting plastic?

Q.

Thermoplastic can be moulded to the desired shape again and again where thermosetting plastics will not change its shape on heating.

1. True

2. False

Q.

Choose the thermoplastics and thermosetting plastics from the following :

Melamine, Polythene, Bakelite, Polyvinyl chloride

Q.

Differentiate between plastic and polythene. [3 MARKS]

Q.

Which of the following statements regarding thermoplastics and thermosetting plastics is/are true?

	Thermoplastics	Thermosetting plastics
A	Soft	Hard
B	Able to withstand heat	Cannot withstand heat
C	No cross-linkages	Cross-linkage present

1. A only

2. B and C only

3. A and C only

4. A, B and C

Q.

Which of the following articles made of plastics 'can be recycled' and which 'cannot be recycled' ? Give reasons for your choice.

Telephone instruments, Plastic toys, Cooker handles , Plastic covering on electrical wires, Electric switches, Ballpoint pens, Carry bags, Plastic bottles, Plastic chairs

Q. Which among the following has cross-linked chains?

1. Bakelite
2. PET
3. Polythene
4. Polyester

Q.

What is the full form of PVC ?

Q.

Which of the two is a thermosetting plastic : PVC or bakelite ?

Q.

What is the difference between different types of plastic?

Q.

Explain the difference between the thermoplastic and thermosetting plastics

Q.

Is bakelite recyclable?

Q.

Thermosetting plastics are very light, strong, durable and can be remoulded after being heated above a specific temperature.

1. False

2. True

Q. is used to make electric switches as well as handles of cooking utensils.

1. PVC
2. Bakelite
3. Malamine

Q.

Explain why the following are made of thermosetting plastics. (a) Saucepan handles (b) Electric plugs/switches/plug boards.

Q. The materials in which monomers are arranged in a straight chain are known as _______.

1. thermosetting plastics
2. melamine
3. thermoplastics
4. bakelite

Q.

Which plastic is used :

(a) for making uniforms of fire-men fire resistant ?

(b) for giving non-stick coating on frying pans?

(c) for making handles of frying pans ?

(d) for making insulation (covering) of electric wires ?

(e) for making electric switches ?

(f) for making flexible water bottles ?

Q.

Explain the difference between polythene and bakelite. [3 MARKS]

Q.

Which among the following are commonly used for making a safety pin?

1. Wood and glass

2. Plastic and glass

3. Leather and plastic

4. Steel and plastic

Q.

Which type of plastic is used in manufacturing toys and combs and why? [2 MARKS]