Balbharati Class 8 General Science Solutions Man made Materials

Welcome to NCTB Solutions. Here with this post we are going to help 8th class students for the Solutions of Balbharati Class 8 General Science Book Chapter 17, Man made Materials. Here students can easily find step by step solutions of all the questions in Man made Materials. Also our Expert Science Teacher’s solved all the problems with easily understandable language with proper guidance so that all the students can understand easily. Here in this post students will get chapter 17 solutions. Here all the Question Answer are based on Balbharati latest syllabus. Here all the question and answer are based on Maharashtra State Board latest syllabus.

Man made Materials Exercise question Solutions :

Question no – (1)

Answer :

(a) Plastic shows Plasticity property, hence it can be moulded to any shape.

(b) Motor cars are coated with Teflon.

(d) Alkali Silicate glass dissolves in water.

Question no – (2)

Answer :

(a) Lead glass → (iii) Electric Bulb

(b) Bakelite → (iv) Electric switches

(c) Thermocol → (i) Plates

(d) Optic glass → (v) Lens

(e) Polypropylene → (ii) Mattress

Question no – (3)

Answer :

(a) Thermocol is produced from polystyrene.

(b) PVC is used to produce bottles, raincoats, pipes, handbags, shoes, electrical cable insulation, furniture, ropes, toys etc.

(c) • Mattress → Polypropylene

• Glass vessels → Sand, Soda ,Lime, Magnesium oxide

• Bangle → plastics

• Chair → wood, plastics

• Gunny bag → Jute

• Broom → plastics, corn husks

• Knife → plastics, steel

• Pen → plastics, brass

(d) The main ingredients of glass are sand, soda, lime and and small amount of magnesium oxide.

(e) Plastics are made up of organic polymers.

Question no – (4)

Answer :

(a) Difference between natural and man made materials are as follows :

Natural materials :

The materials which are found in nature are called natural materials like wood, rocks etc.

Man made materials :

The materials which are produced in factories are called man made materials like glass.

(b) Difference between thermoplastic and thermosetting plastics :

Thermoplastic :	Thermosetting :
• Those plastic gets deformed and bent easily on heating are known as thermoplastic.	• Those plastic which are moulded once can not be softened after heating are known as thermosetting plastic.
• They are soft on heating and are reshaped again.	• They do not soft on heating and not reshaped again.

Question no – (5)

Answer :

(a) The plastic as it is non biodegradable or it takes more than thousand years to degrade harms the environment by polluting the land and water bodies.

In order to save the environment we must reduce our plastic consumption and opt for items made up of degradable materials instead of plastic.

During the production of glass greenhouses gases like sulphur dioxide, nitrogen dioxide and carbon dioxide are released in the atmosphere that are harmful both for the environment and human health. Since it is non biodegradable it can pollute the water bodies and it may block the drains. An easy and effective way to stop glass from harming the environment is to find an alternative for glass or to recycle the used glass products instead of throwing it away.

If a person gets into contact with thermocol for a long duration he may have the possibility of cancers like leukemia and lymphoma he may also face problems with eyes, respiratory system, skin and digestive system, pregnant woman may also has difficulties in carrying child, if the food kept in the thermocol is heated the styrene in it may dissolve and cause serous health problems, liquid styrene can also causes skin burns. Burning the thermocol releases harmful gases and since it is non biodegradable it pollutes the environment.

In order to save the environment we have to find an alternative product to use instead of thermocol and recycle the products made of thermocol.

(b) To minimize the environment problems arising due to non biodegradable problems we must follow the following measures :

Find an biodegradable alternative of the products we use.
Recycle the used up products to make new ones instead of throwing it away.
Reduce the usage of these types of products.

Question no – (6)

Answer :

(a) Glass Production :

Production of glass takes place with mixture of sand, soda lime, and small quantity of magnesium oxide being heated in furnace. Pieces of discarded glasses are added to the mixture in order to melt the mixture at low temperature, after all the ingredients are melted it is heated up to 1500⁰C and immediately cooled. Due to this sudden cooling the mixture becomes homogeneous, amorphous and transparent instead of crystalline. In this way the glass is produced.

(b) Optic glass :

Optical glass is produced from the mixture of sand, soda, limestone, barium oxide and boron. This type of pure glass is useful in production of spectacles, lenses, microscopic, lenses, etc.

(c) Uses of plastic – Plastics are used in the following places are as follows :

Plastics are used to make syringes.
The vessels kept in microwave oven are made up of plastics.
Vehicles are coated with special type of plastic called teflon to protect from scratches.
Some areoplane body parts are made up of plastics.
Polyacrylic plastic is used to produce lenses and artificial teeth.

More Solutions :

👉 Health and Diseases

👉 Current Electricity and Magnetism

👉 Inside the Atom

👉 Composition of Matter

👉 Metals and Nonmetals

👉 Pollution

👉 Disaster Management

👉 Cell and Cell Organelles

👉 Human Body and Organ System

👉 Introduction to Acid and Base

👉 Chemical Change and Chemical Bond