GEO Minerals and Energy Resources (Only Maps) - NCERT Solutions

CBSE Class–10 Social Science
NCERT Solutions

Geography Chapter 5
Minerals and Energy Resources

Question 1: Multiple choice questions.
(i) Which one of the following minerals is formed by decomposition of rocks, leaving a residual mass of weathered material?
(a) coal (b) bauxite (c) gold (d) zinc
(ii) Koderma, in Jharkhand, is the leading producer of which one of the following minerals?
(a) bauxite (b) mica (c) iron ore (d) copper
(iii) Minerals are deposited and accumulated in the strata of which of the following rocks?
(a) sedimentary rocks (b) metamorphic rocks (c) igneous rocks (d) none of the above
(iv) Which one of the following minerals is contained in the Monazite sand?
(a) oil (b) uranium (c) thorium (d) coal

Ans: (i) (b) bauxite
Explanation: Bauxite deposits are formed chiefly by weathering of aluminous rock; some have been transported to their present locations, but most are residual accumulations from which most other constituents of the parent rock, other than alumina, have been leached.
(ii) (b) mica
Explanation: Koderma-Gaya-Hazaribagh belt of Jharkhand is the leading producer of Mica.
(iii) (a) sedimentary rocks
Explanation: In sedimentary rocks, a number of minerals occur in beds and layers.
(iv) (c) thorium
Explanation: Monazite is an important ore for thorium, lanthanum, and cerium. It is often found in placer deposits.

Question2: Answers the following Question in about 30 words:
(i) Distinguish between the following in not more than 30 words.
(a) Ferrous and non-ferrous minerals
(b) Conventional and non-conventional sources of energy.

(ii) What is a mineral?
(iii) How are minerals formed in igneous and metamorphic rocks?
(iv) Why do we need to conserve mineral resources?

Ans: (i) (a)
Ferrous mineralsNon-ferrous minerals
Metallic minerals which contain iron are called ferrous minerals, e.g.. iron ore, manganese, nickel, cobalt, etc. They have small amounts of other metals or elements added, to give the required properties. Ferrous Metals are magnetic and give little resistance to corrosion.Metallic minerals which do not contain iron and are not magnetic and are usually more resistant to corrosion than ferrous metals are called non-ferrous minerals, e.g.. copper, bauxite, tin, etc.
Conventional Sources of EnergyNon-conventional Sources of Energy
Conventional sources of energy are those sources which have been in use since the early times.Non-conventional sources of energy have generally been identified in the recent past.
They are exhaustible except hydro-energy.They are inexhaustible.
They cause pollution when used as they emit smoke and ash.Generally, these are pollution-free.
Their generation and use involve huge expenditure.Low expenditure required.
Very expensive to maintain, store, transmit as they are carried over long distances through transmission grids.Less expensive due to local use and easy maintenance.
Examples are – coal, natural gas, water, fire-wood.Examples are – geothermal energy, solar energy, wind energy, tidal energy, biogas energy, nuclear energy.
(ii) A mineral is a homogeneous, naturally occurring substance with a definable interior structure. They are found in varied forms in nature, ranging from the hardest diamond to the softest talc. A mineral is a naturally occurring chemical compound, usually of crystalline form and not produced by life processes. A mineral has one specific chemical composition, whereas a rock can be an aggregate of different minerals
(iii) In igneous and metamorphic rocks minerals may occur in the cracks, crevices, faults or joints. They are formed when minerals in liquid/ molten and gaseous forms are forced upward through cavities towards the earth’s surface. They then solidify as they rise towards the surface. and form veins or lodes. Minerals like tin, copper, zinc and lead etc. are obtained from veins and lodes.
(iv) It takes millions of years for the formation of minerals. Compared to the present rate of consumption, the replenishment rate of minerals is very slow. Hence, mineral resources are finite and non-renewable. Due to this, it is important that we conserve the mineral resources. Rich mineral deposits are our country's extremely valuable but short lived possessions. Continued extraction of ores leads to increasing costs as mineral extraction comes from greater depths along with a decrease in quality. A concerted effort has to be made in order to use our mineral resources in a planned and sustainable manner.

Question3: Answer the following questions in about 120 words.
(i) Describe the distribution of coal in India.
(ii) Why do you think that solar energy has a bright future in India?
Ans: (i) India has the fifth largest coal reserves in the world, and is the fourth largest producer of coal in the world:
  • The major resources of metallurgical coal belong to the Gondwana age and are located mainly in the northeastern part of the peninsula.
  • Rich reserves of coal are found in the Damodar Valley region in the states of West Bengal and Jharkhand. Raniganj in WestBengal and Jharia and Bokaro in Jharkhand are important coalfields. One third of the total production comes from here.
  • Coal is also found in the Godavari, Mahanadi, Son and Wardha valleys. Korba in Chhattisgarh, Singrauli and Penah-kanhan valley in Madhya Pradesh, Talcher in Orissa, Kamptee and Chandrapur in Maharashtra and Singareni of Andhra Pradesh are important coal mines.
  • Tertiary coal occurs in the northeastern states of Meghalaya, Assam, Arunachal Pradesh and Nagaland.
  • Principal lignite reserves are found in Neyveli in Tamil Nadu. Due to high demand and poor average quality, India is forced to import high quality coal to meet the requirements of steel plants.
  • Dhanbad city is the largest coal producing city.
(ii) Solar energy has a bright future in India because –
  • India being a tropical country receives sunlight in abundance throughout the year.
  • Solar plants can be easily established in rural and remote areas.
  • Photovoltaic technology converts sunlight directly into electricity.
  • It will minimize the dependence of rural households on firewood and dunk cakes which in turn will contribute to environmental conservation and adequate supply of manure in agriculture.