Thermosetting Plastic

Q. Which of the following plastics cannot be remoulded?

1. Polyethylene
2. Melamine
3. Bakelite
4. PVC

Q. Identify the type of plastic that can best be used to make electrical switches.

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

Q. Thermosetting plastics are strong, durable and can be remoulded by heating them.

1. True
2. False

Q. Assertion - Thermosetting plastics cannot be remoulded on heating.

Reason - Formation of strong cross-links during initial moulding gives thermosetting plastics a strong structure.

1. Assertion is correct but the reason is wrong
2. Assertion is wrong but the reason is correct
3. Both assertion and reason are correct
4. Both assertion and reason are wrong

Q. Based on the arrangement of units, all plastics are cross-linked.

1. True
2. False

Q. Who among the following should wear melamine coated clothes?

1. 
2. 
3. 
4. 

Q. Which amongst the following materials can be used to make switchboards?

1. Polystyrene
2. Bakelite
3. Nylon
4. PET

Q. Classify plastics on the basis of effect of heat on them. [2 marks]

Q.

Define an empty polythene bag.

Q.

Write short notes on: (a) Teflon (b) Plastic cookware (c) Melamine [3 MARKS]

Q.

What material is chosen for covering electrical wires and for making handles of screw drivers? [3 MARKS]

Q. Manju had a chain made of pearl which was gifted by her uncle. However, she came to know that it wasn't made of original pearl. From which material do you think the chain was made from?

1. Polystyrene
2. Melamine
3. PET
4. Bakelite

Q. Preethi was unable to penetrate a hot pin through a pipe made out of one of the following materials. The pipe is most probably made of ________.

1. bakelite
2. PET
3. melamine
4. PVC

Q. Identify the material that can be used to make the handles of cooking utensils.

1. Polythene
2. PVC
3. Nylon
4. Bakelite

Q. Which amongst the following materials can be used to make switchboards?

1. Polystyrene
2. Nylon
3. PET
4. Bakelite

Q. Rinit bought a new restaurant and he has to choose a material for the floor and ceiling tiles in kitchen. Which amongst the following substances would be the best choice for Rinit?

1. PET
2. Melamine
3. Terylene
4. PVC

Q. Melamine is fire-resistant.

1. False
2. True

Q. The uniform worn by firefighters has a coating of ________, inorder to make it fire retardant.

1. silk
2. rayon
3. melamine
4. nylon