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🎓 Class 10📖 Contemporary India📖 11 notes🧠 15 Q&A⏱️ ~17 min

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Minerals and Energy Resources

Explanation

Minerals and Energy Resources

This introductory section presents the importance of minerals and energy resources in our daily lives and economic development. It begins with a narrative of Haban, a boy from a remote village, who observes modern vehicles like buses and trains in Guwahati. His father explains that these vehicles are made of metals such as iron and aluminium and require energy to operate, highlighting the connection between minerals and energy. The section emphasizes that minerals are essential for manufacturing everything from tiny pins to large ships, railway lines, roads, machinery, and vehicles. It also points out that minerals are present even in food, underscoring their biological importance. The text introduces minerals as indispensable for human livelihood, decoration, religious rites, and industry. An example is given of toothpaste, which contains minerals like silica, limestone, aluminium oxide, and fluorite for cleaning and cavity prevention. The section encourages students to identify metal items in their homes and locate mineral sources. It also introduces the concept that minerals have varied physical properties such as hardness, colour, crystal form, lustre, and density, which geologists use for classification. The section closes by defining minerals as homogenous, naturally occurring substances with a definable internal structure, setting the stage for deeper study.

  • Minerals are essential for manufacturing everyday items and industrial products.
  • Metals like iron and aluminium are extracted from minerals and used in vehicles and machinery.
  • Minerals are present in food and necessary for biological processes.
  • Toothpaste contains minerals such as silica, fluorite, and mica for cleaning and aesthetics.
  • Minerals vary in physical properties like hardness and lustre, used for classification.
  • Minerals are naturally occurring, homogenous substances with internal structure.
  • 📌 Mineral: A naturally occurring, homogenous substance with a definable internal structure.
  • 📌 Metal: Elements like iron and aluminium extracted from minerals used in manufacturing.
  • 📌 Ore: A mineral or combination of minerals from which metals can be extracted profitably.

What is a Mineral?

Explanation

What is a Mineral?

This section elaborates on the definition and characteristics of minerals. Minerals are defined by geologists as homogenous, naturally occurring substances with a definable internal structure. The section explains that minerals vary widely in their physical properties such as hardness, colour, crystal form, lustre, and density due to the different physical and chemical conditions under which they form. It highlights that rocks are combinations of minerals; some rocks like limestone consist of a single mineral, while most rocks contain several minerals in varying proportions. Over 2000 minerals have been identified, but only a few are commonly found in rocks. The formation of a particular mineral depends on the elements involved and the environmental conditions during formation. The section also distinguishes the roles of geographers and geologists: geographers study minerals as part of the earth's crust to understand landforms and economic activities, while geologists focus on mineral formation, age, and composition. For commercial purposes, minerals are classified based on their mode of occurrence and economic value.

  • Minerals are naturally occurring, homogenous substances with internal structure.
  • Minerals vary in properties due to formation conditions.
  • Rocks are combinations of minerals; some rocks have a single mineral.
  • Over 2000 minerals identified; few are abundant in rocks.
  • Geographers study minerals for landforms and economic distribution.
  • Geologists study mineral formation, age, and composition.
  • 📌 Mineral: Homogenous, naturally occurring substance with definable internal structure.
  • 📌 Rock: A combination of one or more minerals.
  • 📌 Geologist: Scientist who studies mineral formation and composition.

Mode of Occurrence of Minerals

Explanation

Mode of Occurrence of Minerals

This section explains the various geological formations where minerals are found and how these affect mining and extraction. Minerals are usually found in ores, which are mineral accumulations mixed with other elements. The concentration of minerals

Practice Questionsto work.”

15 practice questions with detailed answers

Q1.Which of the following best defines a mineral according to geologists?
A.A) A naturally occurring, homogenous substance with a definable internal structure
B.B) Any rock found in the earth's crust
C.C) A man-made substance used in industry
D.D) A mixture of various elements without a fixed composition

Answer:

A naturally occurring, homogenous substance with a definable internal structure

Explanation:

Geologists define minerals as naturally occurring substances that are homogenous and have a definable internal structure. This distinguishes minerals from rocks, which are combinations of minerals, and from man-made substances or mixtures.

Easy
Q2.Which of the following minerals is primarily used in toothpaste to reduce cavities?
A.A) Fluorite
B.B) Silica
C.C) Mica
D.D) Limestone

Answer:

Fluorite

Explanation:

Fluoride used to reduce cavities in toothpaste comes from the mineral fluorite. Silica and limestone act as abrasives, and mica adds sparkle, but fluoride specifically helps prevent cavities.

Easy
Q3.Minerals are found in various forms in nature. Which property is NOT commonly used by geologists to classify minerals?
A.A) Hardness
B.B) Colour
C.C) Taste
D.D) Lustre

Answer:

Taste

Explanation:

Geologists classify minerals based on properties like hardness, colour, crystal form, lustre, and density. Taste is not a standard classification property for minerals.

Medium
Q4.Which of the following modes of occurrence describes minerals found in cracks, crevices, faults, or joints of igneous and metamorphic rocks?
A.A) Veins and lodes
B.B) Beds in sedimentary rocks
C.C) Placer deposits
D.D) Residual deposits

Answer:

Veins and lodes

Explanation:

Minerals occurring in cracks, crevices, faults, or joints of igneous and metamorphic rocks are called veins (small occurrences) and lodes (larger occurrences).

Easy
Q5.What type of mineral deposit is formed by the decomposition of surface rocks and removal of soluble constituents, leaving weathered material rich in ores?
A.A) Residual deposits
B.B) Placer deposits
C.C) Beds in sedimentary rocks
D.D) Veins and lodes

Answer:

Residual deposits

Explanation:

Residual deposits form when surface rocks decompose and soluble constituents are removed, leaving a residual mass rich in mineral ores such as bauxite.

Medium
Q6.Which mineral is NOT typically found in placer deposits?
A.A) Gold
B.B) Silver
C.C) Copper
D.D) Platinum

Answer:

Copper

Explanation:

Placer deposits contain minerals resistant to corrosion by water such as gold, silver, tin, and platinum. Copper is not commonly found in placer deposits.

Medium
Q7.Assertion (A): Rat-hole mining is a legal and safe mining method in Meghalaya. Reason (R): Rat-hole mining involves long narrow tunnels dug by family members to extract coal. Choose the correct option:
A.A) Both A and R are true and R is the correct explanation of A
B.B) Both A and R are true but R is NOT the correct explanation of A
C.C) A is false but R is true
D.D) A is true but R is false

Answer:

C

Explanation:

Assertion is false because rat-hole mining is illegal and unsafe as declared by the National Green Tribunal. Reason is true as rat-hole mining involves narrow tunnels dug by family members. However, the legality and safety concerns make the assertion incorrect.

Medium
Q8.Which of the following Indian states is NOT a major producer of iron ore?
A.A) Odisha
B.B) Jharkhand
C.C) Rajasthan
D.D) Karnataka

Answer:

Rajasthan

Explanation:

Major iron ore producing states include Odisha, Jharkhand, Karnataka, and Chhattisgarh. Rajasthan is not a major producer of iron ore but has reserves of non-ferrous minerals.

Medium