Some important MCQs with explanations related to Economic Geology for the Jharkhand Academic Council (JAC) 12th Exam -3

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21. Which mineral is known as “fool’s gold”?

A. Pyrite
B. Chalcopyrite
C. Hematite
D. Magnetite

Correct Answer: A. Pyrite
Explanation:
Pyrite, with its metallic luster and pale brass-yellow hue, resembles gold but is chemically iron sulfide (FeS₂).
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22. Which of the following is a non-metallic mineral?

A. Bauxite
B. Limestone
C. Magnetite
D. Chromite

Correct Answer: B. Limestone
Explanation:
Limestone is a non-metallic mineral composed mainly of calcium carbonate, used in construction and cement manufacturing.

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23. Which Indian state is the largest producer of coal?

A. Jharkhand
B. Odisha
C. Chhattisgarh
D. West Bengal

Correct Answer: A. Jharkhand
Explanation:
Jharkhand has the largest reserves and is the leading producer of coal in India, especially from mines like Jharia and Bokaro.

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24. What is the chief ore of aluminum?

A. Magnetite
B. Bauxite
C. Hematite
D. Cassiterite

Correct Answer: B. Bauxite
Explanation:
Bauxite is the primary ore of aluminum, consisting of hydrated aluminum oxides.
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25. What is the common method used for the extraction of iron from its ore?

A. Smelting
B. Froth Flotation
C. Leaching
D. Distillation

Correct Answer: A. Smelting
Explanation:
Iron is extracted from its ore (hematite or magnetite) in a blast furnace using the smelting process, where it is reduced to molten iron.

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26. Which rock type is commonly associated with metallic mineral deposits?

A. Igneous rocks
B. Sedimentary rocks
C. Metamorphic rocks
D. All of the above

Correct Answer: A. Igneous rocks
Explanation:
Many metallic minerals, such as copper and gold, are associated with igneous and hydrothermal processes.

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27. What is the name of the process used to concentrate low-grade ores?

A. Smelting
B. Froth Flotation
C. Roasting
D. Refining

Correct Answer: B. Froth Flotation
Explanation:
Froth flotation is a method used to separate valuable minerals from low-grade ores by utilizing differences in surface properties.

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28. Which mineral is the primary source of iron in India?

A. Magnetite
B. Hematite
C. Limonite
D. Siderite

Correct Answer: B. Hematite
Explanation:
Hematite (Fe₂O₃) is the most abundant and economically important source of iron in India, found in states like Jharkhand, Odisha, and Chhattisgarh.

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29. Which mineral is used for making electrical wires?

A. Iron
B. Copper
C. Zinc
D. Lead

Correct Answer: B. Copper
Explanation:
Copper is an excellent conductor of electricity, making it ideal for electrical wiring.

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30. Which region in Jharkhand is famous for its uranium reserves?

A. Jharia
B. Jaduguda
C. Bokaro
D. Ranchi

Correct Answer: B. Jaduguda
Explanation:
Jaduguda in Jharkhand is known for its uranium mines,

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