Distinguish between Ferrous and Non-ferrous minerals.
Ferrous Minerals:
Content: Contain iron content.
Importance: They account for about three-fourths of the total value of the production of metallic minerals. They provide a strong base for the development of metallurgical industries.
Examples: Iron ore, Manganese, Nickel, Cobalt.
Non-ferrous Minerals:
Content: Do not contain iron.
Importance: India’s reserves and production are not very satisfactory. However, they are vital for engineering and electrical industries.
Examples: Copper, Bauxite, Lead, Zinc, Gold.
Question 2
What is a mineral?
Geologists define a mineral as a “homogenous, naturally occurring substance with a definable internal structure.”
Minerals are found in varied forms in nature, ranging from the hardest diamond to the softest talc. They are an indispensable part of our lives; almost everything we use, from a tiny pin to a towering building or a big ship, is made from minerals.
Question 3
Distinguish between Conventional and Non-conventional sources of energy.
Conventional Sources:
Usage: Have been in use for a long time.
Nature: Generally non-renewable and cause pollution.
Examples: Firewood, cattle dung cake, coal, petroleum, natural gas, and electricity (both hydel and thermal).
Non-conventional Sources:
Usage: Relatively new in terms of widespread commercial use.
Nature: Renewable and eco-friendly.
Examples: Solar, wind, tidal, geothermal, biogas, and atomic energy.
Long Answer Questions
Question 1
Describe the mode of occurrence of minerals. Where are these minerals found?
Minerals generally occur in these forms:
Igneous and Metamorphic Rocks: Minerals may occur in the cracks, crevices, faults, or joints. Smaller occurrences are called veins and larger ones are called lodes. (e.g., Tin, Copper, Zinc, Lead).
Sedimentary Rocks: Minerals occur in beds or layers. They are formed as a result of deposition, accumulation, and concentration in horizontal strata. (e.g., Coal, Iron ore, Gypsum, Potash).
Decomposition of Surface Rocks: This involves the removal of soluble constituents, leaving a residual mass of weathered material containing ores. (e.g., Bauxite).
Alluvial Deposits: Certain minerals occur as alluvial deposits in sands of valley floors and the base of hills. These are called Placer deposits and are not corroded by water. (e.g., Gold, Silver, Tin, Platinum).
Ocean Waters: Ocean waters contain vast quantities of minerals, though most are too widely diffused for economic extraction. (e.g., Common salt, Magnesium, Bromine).
Question 2
Why do we need to conserve mineral resources?
Conservation is necessary because:
Finite and Non-Renewable: Mineral deposits are a finite and non-renewable asset. The total workable mineral deposits are an insignificant fraction (1%) of the earth’s crust.
Slow Formation: The geological processes of mineral formation are so slow that the rates of replenishment are infinitely small compared to the present rates of consumption.
Increasing Cost: As extraction goes deeper, the cost increases while quality often decreases.
Future Generations: We must use our mineral resources in a planned and sustainable manner to ensure they are available for future generations.
Question 3
“India has vast potential of solar energy.” Elucidate the statement.
India is a tropical country and has enormous possibilities of tapping solar energy:
Photovoltaic Technology: This technology converts sunlight directly into electricity. It is becoming popular in rural and remote areas.
Rural Application: The big power plants are being established in different parts of India (e.g., Bhadla Solar Park). This will minimize the dependence of rural households on firewood and dung cakes.
Environmental Benefit: By reducing reliance on firewood, it contributes to environmental conservation and ensures an adequate supply of manure for agriculture.
Future: Solar energy is expected to be one of the most important non-conventional energy sources for India’s energy security.