Chapter-3 Synthetic fibres and plastics

Explanation:

Certain artificial (man-made) fibres are referred to as synthetic because they are produced through the chemical processing of petrochemicals. Large units known as polymers make up the synthetic fibres. A few examples of synthetic fibres are acrylon, nylon, and rayon.

Explanation:

For preserving food, plastic containers are preferred for the following reasons:

Due to their small weight, plastic containers are simple to handle.

Plastic containers cost a lot less than other types of containers.

They are physically strong.

Polypropylene containers survive a long time.

Explanation:

Plastic containers are useful for storing a variety of chemicals and other things since they are non-reactive and do not react with water or air.

Non-stick cookware is made with a coating made of a material called Teflon.

Since bakelite is a bad conductor of heat and electricity, it is utilised to make utensil handles and electric switch housings.

Kitchenware and floor tiles are both made of melamine.

Explanation:

We'll create a circuit to demonstrate how poorly thermoplastics carry electricity. We require a plastic pipe, a bulb, some cables, a battery, and a piece of metal. Build the circuit using the metal first, then the plastic pipe (as shown in the figure). In the first scenario, you will see that the bulb illuminates after turning on the current. The light does not glow in the latter situation. As a result, it is demonstrated that a plastic pipe

Explanation:

Polymers cannot decompose biologically. They take several years to break down once they are released into the environment. Pollution of the environment is increased by plastics. They cannot be burned since doing so would produce harmful fumes. Animals like cows ingest plastic bags that are tossed in the trash. These plastic bags suffocate their airways and may possibly be fatal. As a result, we should limit  use plastics.

Explanation:

Because natural fibres must be obtained from plants, which necessitates the removal of numerous trees, the production of synthetic fibres aids in the preservation of forests. This shows to be advantageous for forest preservation.

Explanation:

We will create a circuit to demonstrate that thermoplastic is a bad conductor of electricity. A light, some cables, a battery, a piece of metal, and a piece of plastic pipe are required for that (as shown in the figure below). Turn on the current after setting up the experiment, and you'll see that the bulb glows in the first scenario. The light does not glow in the latter situation. As a result, it is demonstrated that a plastic pipe—a thermoplastic—is a poor conductor of electricity.

Explanation:

As plastics are not biodegradable in nature, we should try to limit our usage of them. They pollute the environment once they are released. The plastic bags dumped in the trash dump are swallowed by animals, choking their respiratory systems and killing them. If burned, they release poisonous gases.

Explanation:

As plastics are naturally non-corrosive, they won't react even when exposed to potent chemicals. For instance, plastic bottles rather than metal containers are used to store the cleaning supplies we use at home.

Explanation:

a) Because thermosetting plastics are poor heat conductors and do not soften when heated, they are utilised to construct saucepan handles.

b) Bakelite is a type of thermosetting material that conducts electricity and heat poorly. This characteristic allows it to be utilised to create electrical plugs, switches, plug boards, etc.

Explanation:

The samples that follow show that nylon fibres are incredibly strong:

Rock climbing parachutes and ropes are constructed of nylon.

Fishing nets, seat belts, and tyre cables are all made of nylon.

Rackets and other sporting goods are made of nylon.

Explanation:

The following techniques can be used to reduce pollution caused by plastics:

Plastic usage should be limited as much as possible.

Use cotton or jute bags.

Wastes that decompose biologically and those that do not should be sorted and disposed of separately.

Polymers ought to be reused and recycled.

13.“Even though plastics are very useful, they are not environment friendly.” Justify the statement. 

Explanation:

The following techniques can be used to reduce pollution caused by plastics:

Plastic usage should be limited as much as possible.

Use cotton or jute bags.

Wastes that decompose biologically and those that do not should be sorted and disposed of separately.

Polymers ought to be reused and recycled.

Plastics are utilised in healthcare.

for creating a variety of medical devices, including syringes, doctor gloves, threads for sewing wounds, and packaging for tablets.

Explanation:

Fabric made of synthetics readily catches fire. When worn, it melts and adheres to the wearer's flesh. Synthetic fibres do not wick away perspiration during the summer, making a person wearing them uncomfortable.

Explanation:

The buckets made of iron rust, but the buckets made of plastic do not.

Plastic containers can be used to keep food since they are resistant to chemicals in the food.

Teflon-coated pans are preferred over metallic ones since they won't react with the chemicals in food.

Explanation:

Rana needs to purchase cotton shirts. Cotton clothing is recommended in the summer because it wicks away perspiration and keeps the wearer cool, as opposed to synthetic materials, which do not wick away perspiration and make the wearer uncomfortably hot.

Explanation:

Strong nylon fibres are available. Making parachutes and rock-climbing ropes using it are both common uses. Their use demonstrates the high tensile strength of nylon fibres.

Explanation:

No. A tooth brush's handle and bristles ought to be constructed of distinct materials. The bristles of a toothbrush should be soft and flexible, while the handle should be sturdy and firm.