CBSE Book Class 8 Science Activity Interview

 SYNTHETIC FIBRES AND PLASTICS

An interview board comprising of the selectors namely Rachna and Guni was constituted to conduct interviews of different synthetic fibres and plastics and to make a merit list of the candidates based on their structure and characteristic properties.  The candidates appearing for the interview include- Rayon, Nylon, Polyester, Acrylic, Polythene, PVC,  Bakelite and Melamine. All the candidates appeared before the board in the order of their names as shown above. The process began in the office of 'Science light'.  Rayon entered the room and greeted the board members with a smile.

At the end the board concludes the following:

1.  Rayon, nylon, polyester and acrylic are synthetic fibres and all of these have specific properties  and uses in daily life. 

2.  Polyester and PVC are thermoplastics and these can be reused and remoulded by heating.

3.  Bakelite  and  melamine  are  thermosetting  material  and  thus  these  cannot  be  reused  and  remoulded.

4.  All these materials are useful in daily life but efforts should be made to reuse and recycle the  material, if possible. Children in the class maybe assigned the names of these polymers. They should be asked to learn their  formation and characteristics. Two students can be assigned the duty of interview board and the whole  drama can be enacted in class.

Some candidates with common background were interviewed together in groups:

Group I : Polyester and acrylic

Rachna : What is common to both of you?

P and A : Both of us synthetic fibres are produced by a number of processes using raw material of petroleum origin, called petrochemicals.

Guni : Describe your different properties and uses.

Polyetser : I am used in making bottles, utensils, films, wires etc.

Acrylic : I am used as a substitute for wool, in making sweaters, shawls or blankets. Thus I am poor man's wool. Group I leaves the room.

Group II : 'Polythene and PVC entered the room very softly.

Rachna :  What is your origin?

P and P : We are man made materials formed by the joining of several identical chemical units.

Guni : What are your characteristic properties and uses?

P and P : Both of us are thermoplastics and thus can be recycled, re-used, remoulded very easily by heating. We are used in the making of toys, combs, containers etc.

Group II leaves the room.

Group III : Bakelite and Melamine:

Rachna : What is common to both of you?

B and M : We are thermosetting plastics because we cannot be softened by heating or remoulded.

Guni : What are your uses?

Bakelite : I am used in making of electrical switches, handles of various utensils because I am a poor conductor of heat and electricity.

Melamine : As I can resist fire better than other plastics, hence I am used in making floor tiles,

Please refer to the link below - CBSE Class 8 Science Activity Interview