Experiment 11 — Choose the Right Fabric

Topic: Chemistry · Class 8 · Synthetic fibres and plastics

Aim: Choose the best fabric for a raincoat — and test it properly before deciding.

Daily: Cotton kurtas for a Chennai summer, nylon for a raincoat, polyester in school uniforms that need no ironing, and acrylic sweaters for a Shimla winter — every choice is a property matched to a use.

Note: absorbs sweat, comfortable, from a plant

Note: strong, elastic, water-repellent, from chemicals

Note: crease-resistant, dries fast

Question: Which fabric would keep you driest in the rain?

Exp: Nylon is synthetic and water-repellent; cotton absorbs water readily.

Question: Which is a natural fibre?

Exp: Cotton comes from a plant; the others are synthetic.

Question: Thermoplastics such as polythene…

Exp: Thermosetting plastics such as bakelite do not soften.

Question: Bakelite is used for electrical switches because it is…

Exp: It insulates and does not soften when warm.

Question: The main environmental problem with plastics is that they are…

Exp: They persist in soil and water for a very long time.