CBSE Class 10 Social Science Minerals and Energy Resources MCQs Set 06

Answer: (b) On earth's crust

Explanation:
1. Minerals occur within the earth's crust, typically in igneous, metamorphic or sedimentary rocks.

Teacher's Note:
a) Minerals are found in the earth's crust, not its core.
b) They occur within different rock types depending on how they formed.

Answer: (b) Rat-hole mining

Explanation:
1. This informal method, practised in places like Jowai and Cherrapunjee in Meghalaya, is called rat-hole mining.

Teacher's Note:
a) Rat-hole mining is done through long, narrow tunnels by individuals or communities.
b) It is notably practised in parts of Meghalaya.

Answer: (a) Veins and lodes

Explanation:
1. In igneous and metamorphic rocks, minerals occur in cracks, crevices, faults or joints — the smaller occurrences are veins, the larger ones lodes.

Teacher's Note:
a) Veins and lodes form in igneous and metamorphic rocks.
b) Sedimentary rocks, by contrast, hold minerals in layers or beds.

Answer: (a) Talc

Explanation:
1. Talc is used as a benchmark for softness in mineral classification and is the softest mineral on the list.

Teacher's Note:
a) Talc is classified as the softest known mineral.
b) This is why it is used in products like talcum powder.

Answer: (a) Only I and II

Explanation:
1. Major metallic minerals like zinc and copper are obtained from veins and lodes in igneous and metamorphic rocks.
2. Coal occurs in sedimentary layers, and bauxite forms through the decomposition of surface rocks — neither comes from veins and lodes.

Teacher's Note:
a) Zinc and copper are vein/lode minerals from igneous and metamorphic rocks.
b) Coal (sedimentary layers) and bauxite (residual decomposition) form differently.

Answer: (c) (IV), (I), (III) and (II)

Explanation:
1. Floodgate dams are built first (IV); then high tide water flows in (I); the gate closes, trapping the water (III); and as the tide falls, water flows back through the turbine (II).

Teacher's Note:
a) Tidal power sequence: build dam → high tide fills inlet → gate traps water → falling tide drives turbine.
b) This is how tidal energy is harnessed to generate electricity.

Answer: (c) Geologist

Explanation:
1. A geologist studies mineral formation, age, and physical/chemical composition.

Teacher's Note:
a) Geologists study mineral formation, age and composition.
b) Geographers instead focus more on mineral distribution and its economic/human impact.

Answer: (b) Statements (I), (II) and (III) are appropriate

Explanation:
1. Mica's plate-like structure, varied colours, and use in electrical/electronic industries (I, II, III) are all accurate; smelting iron ore in a blast furnace is unrelated to mica (that uses coke and limestone), making IV incorrect.

Teacher's Note:
a) Mica's layered structure, colour range and electrical uses are all genuine characteristics.
b) Smelting iron ore uses coke and limestone, not mica, so IV is wrong.

Answer: (b) Bauxite

Explanation:
1. Bauxite is the ore from which aluminium is extracted.

Teacher's Note:
a) Bauxite is the raw material for aluminium production.
b) Hematite is an iron ore; galena and sphalerite are lead/zinc ores.

Answer: (c) North-eastern states

Explanation:
1. Tertiary coal deposits occur in the north-eastern states of India, such as Assam, Meghalaya, Nagaland and Arunachal Pradesh.

Teacher's Note:
a) Tertiary coal is found in India's north-eastern states.
b) This differs from the older Gondwana coal deposits found elsewhere in India.

Answer: (b) Natural Gas reserve in Gujarat

Explanation:
1. The Cambay Basin in Gujarat also hosts a natural gas reserve, alongside the Ankleshwar oilfield.

Teacher's Note:
a) The Cambay Basin (Gujarat) holds both oil (Ankleshwar) and natural gas reserves.
b) This makes Gujarat a key petroleum/gas-producing region.

Answer: (c) Hematite, Anthracite

Explanation:
1. Hematite is an iron ore, while anthracite is a type of coal — mixing an ore with a coal type makes this pair the odd one out, unlike the other pairs, which are all coal-type combinations.

Teacher's Note:
a) Hematite (iron ore) and Anthracite (coal) don't belong to the same mineral category.
b) The other pairs are all coal types (anthracite, bituminous, peat, lignite).

Answer: (c) Lodes

Explanation:
1. Larger occurrences of minerals in such cracks/faults are called lodes (smaller occurrences are veins).

Teacher's Note:
a) Lodes are the larger mineral occurrences in rock cracks/faults.
b) Veins are the smaller version of the same phenomenon.

Answer: (a) Geothermal Energy

Explanation:
1. Manikaran, Himachal Pradesh, is known for harnessing geothermal energy from its hot springs.

Teacher's Note:
a) Manikaran is a known geothermal energy site in Himachal Pradesh.
b) It takes advantage of naturally occurring hot springs.

Answer: (b) Damodar valley

Explanation:
1. Gondwana coal deposits are found in the Damodar Valley region.

Teacher's Note:
a) Gondwana coal is concentrated in the Damodar Valley.
b) This is India's primary source of good-quality coal.

Answer: (d) The mineral contains iron

Explanation:
1. By definition, ferrous minerals are those that contain iron.

Teacher's Note:
a) Containing iron is the defining feature of a ferrous mineral.
b) The other options describe unrelated or non-defining properties.

Answer: (b) Assam and Gujarat

Explanation:
1. Assam and Gujarat together hold most of India's petroleum deposits.

Teacher's Note:
a) Assam and Gujarat are India's major petroleum-producing states.
b) Assam is the oldest oil-producing state; Gujarat is a major modern producer.

Answer: (a) (A)-(III), (B)-(IV), (C)-(I), (D)-(II)

Explanation:
1. Potash is a sedimentary mineral (III); tin is a metallic mineral (IV); manganese is a ferrous mineral (I); and coal is an energy resource (II).

Teacher's Note:
a) Potash = sedimentary; Tin = metallic.
b) Manganese = ferrous; Coal = energy resource.

Answer: (a) Both (A) and (R) are true and (R) is the correct explanation of (A)

Explanation:
1. Groundwater does get heated by surrounding rocks, and this is correctly explained by the Earth's increasing temperature with depth, which is the basis of geothermal energy.

Teacher's Note:
a) Earth's heat increases with depth, warming groundwater near hot rocks.
b) This natural process is exactly what geothermal energy harnesses.

Answer: (c) Manganese

Explanation:
1. Manganese hardens steel; about 10 kg is needed per tonne of steel.

Answer: (a) Cement Industry

Explanation:
1. Limestone is the key raw material for cement manufacturing.