A. Tick (✔) the correct option.
DAV Class 8 SST Solutions – Natural Resources, Minerals & Energy (Chapter-wise Answers)
1. Which one of the following is not a characteristic of rocks?
(a) These are composed of mineral crystals.
(b) These have a definite mineral composition. ✔
(c) These vary in hardness and colour.
(d) These form outermost shell of the earth.
👉 Answer: (b) These have a definite mineral composition.
2. Which one of the following is the best quality of coal?
(a) lignite
(b) bituminous
(c) anthracite ✔
(d) peat
👉 Answer: (c) anthracite
3. The major oilfields of India are located in which one of the following states of India?
(a) Assam ✔
(b) Rajasthan
(c) Bihar
(d) Tamil Nadu
👉 Answer: (a) Assam
4. The metallic minerals used in electrical industry are—
(a) copper and bauxite ✔
(b) iron and copper
(c) mica and manganese
(d) bauxite and iron
👉 Answer: (a) copper and bauxite
5. Petroleum is not extracted from the oilfields of North Sea by—
(a) United Kingdom
(b) Denmark
(c) Norway
(d) Sweden ✔
👉 Answer: (d) Sweden
✅ Final Answers (Quick View)
- (b)
- (c)
- (a)
- (a)
- (d)
👇
📘 B. Fill in the blanks.
1. A mineral is extracted from the region where its concentration is __________.
👉 Answer: high
2. __________ minerals are divided into ferrous and non-ferrous.
👉 Answer: Metallic
3. __________ is obtained from bauxite ore.
👉 Answer: Aluminium
4. Petroleum, coal, __________ and hydroelectricity are conventional sources of energy.
👉 Answer: natural gas
5. __________ and __________ are the major types of iron ore.
👉 Answer: Hematite and Magnetite
📘 C. Write a technical term or an appropriate word for each of the following statements.
1. Energy generated by turbines run by water falling from a height.
👉 Answer: Hydroelectricity
2. The resultant metal with improved strength which is produced by mixing two or more than two metals.
👉 Answer: Alloy
3. Materials formed inside the earth by the decomposition of dead remains of plants and animals in sedimentary rocks.
👉 Answer: Fossil fuels
4. Mineral deposits that are formed when a river erodes rock constituents from a primary source and deposits them in the river beds.
👉 Answer: Alluvial deposits
5. The process of extracting minerals from the earth’s crust.
👉 Answer: Mining
✅ Final Quick Summary
B Answers:
- High
- Metallic
- Aluminium
- Natural gas
- Hematite and Magnetite
C Answers:
- Hydroelectricity
- Alloy
- Fossil fuels
- Alluvial deposits
- Mining
👇
📘 D. Answer the following questions in brief.
1. What is a mineral? Mention the three main processes of mineral extraction.
👉 Answer:
A mineral is a naturally occurring substance with a definite chemical composition found in the earth’s crust.
The three main processes of mineral extraction are:
- Mining
- Drilling
- Quarrying
2. What is tidal energy? How can it be harnessed?
👉 Answer:
Tidal energy is the energy obtained from the rise and fall of ocean tides.
It can be harnessed by constructing dams or barrages across tidal areas. The flowing water turns turbines to generate electricity.
3. Why do we need to conserve mineral resources? Explain any three reasons.
👉 Answer:
We need to conserve mineral resources because:
- Minerals are limited and non-renewable
- They take millions of years to form
- Excessive use may lead to depletion
4. What are two types of energy sources? Which one of them is a better resource and why?
👉 Answer:
Two types of energy sources are:
- Conventional sources (coal, petroleum, natural gas)
- Non-conventional sources (solar, wind, tidal energy)
Non-conventional sources are better because they are renewable, less polluting, and sustainable.
5. Highlight any three advantages of using nuclear energy.
👉 Answer:
Advantages of nuclear energy:
- Produces a large amount of energy
- Causes less pollution
- Requires a small amount of fuel
👇
📘 E. Answer the following questions in detail.
1. Describe the different types of rocks and their formation.
👉 Answer:
Rocks are naturally occurring solid masses that make up the earth’s crust. Based on their formation, rocks are classified into three main types:
(i) Igneous Rocks:
These rocks are formed when molten magma cools and solidifies. When cooling happens inside the earth, intrusive rocks like granite are formed. When lava cools on the surface, extrusive rocks like basalt are formed. These rocks are hard and do not contain fossils.
(ii) Sedimentary Rocks:
These rocks are formed by the deposition, compaction, and cementation of sediments over long periods. Rivers, wind, and water carry these sediments. Examples include sandstone and limestone. These rocks often contain fossils.
(iii) Metamorphic Rocks:
These rocks are formed when existing rocks are subjected to heat and pressure inside the earth. This changes their structure and composition. For example, marble is formed from limestone and slate from shale.
Thus, rocks are continuously formed, broken, and transformed through natural processes.
2. Explain the classification of minerals with examples.
👉 Answer:
Minerals are classified into two main types:
(i) Metallic Minerals:
These minerals contain metals and can be melted to obtain new products. They are further divided into:
- Ferrous minerals: Contain iron (e.g., iron ore, manganese)
- Non-ferrous minerals: Do not contain iron (e.g., copper, bauxite)
(ii) Non-metallic Minerals:
These minerals do not contain metals and are used in various industries. Examples include mica, limestone, and gypsum.
Minerals are essential for industrial development and economic growth.
3. Discuss the distribution of major minerals in India.
👉 Answer:
India is rich in mineral resources, but their distribution is uneven.
- Iron ore: Found in Odisha, Jharkhand, Chhattisgarh, and Karnataka
- Coal: Located mainly in Jharkhand, West Bengal, Chhattisgarh, and Odisha
- Petroleum: Found in Assam, Gujarat, and offshore areas like Mumbai High
- Bauxite: Found in Odisha, Gujarat, Jharkhand, and Maharashtra
These minerals play an important role in industrial development.
4. Explain different sources of energy and their importance.
👉 Answer:
Energy sources are broadly classified into two types:
(i) Conventional Sources:
These include coal, petroleum, natural gas, and hydroelectricity. They are widely used but are limited and cause pollution.
(ii) Non-Conventional Sources:
These include solar energy, wind energy, tidal energy, and nuclear energy. These sources are renewable and eco-friendly.
Importance of Energy:
- Essential for industrial development
- Helps in transportation and communication
- Improves standard of living
- Supports agricultural activities
Thus, energy is vital for economic growth and development.
5. Why is conservation of resources necessary? Suggest measures to conserve them.
👉 Answer:
Conservation of resources is necessary because resources are limited and their overuse can lead to depletion.
Reasons for conservation:
- Resources are finite in nature
- Increasing population leads to higher demand
- Environmental degradation due to overuse
Measures to conserve resources:
- Use resources wisely and avoid wastage
- Promote recycling and reuse
- Use alternative sources of energy
- Spread awareness about conservation
Proper conservation ensures sustainable development for future generations