CBSE Class 10 Social Science Minerals and Energy Resources Important Questions Set 05

Important Questions

Teacher's Note:
a) Anthracite is the rarest and highest grade of coal in India, found only in J&K.
b) Carbon content is the key number: 80%+ for anthracite, 60-80% for bituminous.

Question 2. Why is conservation of minerals essential? Explain any four measures to conserve minerals.
Answer:
(1) In India, sustainable economic development means development should take place without damaging the environment, and development in the present should not compromise the needs of future generations.
(2) Minerals are a good source of earning foreign currency.
(3) Many Indian factories depend upon minerals for their raw materials.
(4) Minerals are helpful in generating jobs and employment in mining.

Teacher's Note:
a) Minerals are non-renewable — the sustainable-development angle is the key reasoning here.
b) Four reasons given: environment, foreign currency, industry, employment.

Question 3. Describe any three points on the importance of minerals in our daily life.
Answer:
Minerals are an indispensable part of our lives. For example:
(1) Railway lines, the tarmac of roads, and our implements and machinery are made from minerals.
(2) Cars, buses, trains and aeroplanes are manufactured from minerals.
(3) From a tiny pin to a towering building or a ship, all are made from minerals.
(4) At all stages of development, human beings have used minerals for their livelihood, decoration, festivities, and religious and ceremonial rites.

Teacher's Note:
a) Give at least one everyday example (transport, buildings) and one cultural example (decoration/rites) for a well-rounded answer.

Teacher's Note:
a) A rock is made of minerals — think of rocks as the mixture, minerals as the ingredients.
b) Diamond (hardest) and talc (softest) are the standard example pair for mineral hardness.

Question 5. Classify minerals into three groups. Give one example of each.
Answer:
(1) Metallic minerals, further classified into:
(i) Ferrous (containing iron): for example, iron ore, manganese, nickel, cobalt.
(ii) Non-ferrous: for example, copper, lead, tin, bauxite.
(iii) Precious: for example, gold, silver, platinum.
(2) Non-metallic minerals: for example, mica, salt, potash, granite, limestone.
(3) Energy minerals: for example, coal, petroleum, natural gas.

Teacher's Note:
a) Three main groups — metallic, non-metallic, energy — with metallic further split into ferrous/non-ferrous/precious.
b) Iron ore (ferrous) and coal (energy) are the two most commonly cited examples.

Question 6. Explain the various hazards of mining.
Answer:
(1) The dust and noxious fumes inhaled by miners make them vulnerable to pulmonary (lung) diseases.
(2) The risk of collapsing mine roofs, flooding and fires in coal mines is a constant threat to miners.
(3) Dumping of waste and slurry leads to degradation of land and soil.
(4) During rainfall, water falling on the dumped waste becomes dirty and ultimately contaminates surrounding water bodies (streams or rivers), or groundwater through percolation.
(5) The mining industry is often called a ‘killer industry’ due to the high risks involved.

Teacher's Note:
a) Group the hazards as health-related (dust, fumes), safety-related (collapses, fires) and environmental (waste, water pollution).
b) ‘Killer industry’ is a specific phrase sometimes directly asked for.

Question 7. ‘Crude oil reserves are limited all over the world. If people continue to extract it at the present rate, the reserves would last only 35-40 years more.’ Explain any three ways to solve this problem.
Answer:
Crude oil is a non-renewable resource of energy. It takes millions of years for this fuel to form, so it must be used judiciously. It is being used at a faster rate than it is being produced, causing depletion and scarcity.
Steps that can be taken to conserve this resource:
(i) Use of public transport like buses and trains instead of self-owned vehicles will help conserve petroleum; carpooling will further reduce fuel consumption.
(ii) Use of cycles wherever possible, instead of motorbikes or cars.
(iii) Using beeswax instead of petroleum-based commercial wax for waxing floors.

Teacher's Note:
a) Three practical conservation steps — public transport, cycling, and substituting petroleum products are the pattern to remember.
b) This question links to the 'steps to save energy' question below — revise together.

Question 8. What steps can be taken for saving energy?
Answer:
(1) Use more public transport and fewer individual vehicles.
(2) Use bicycles for short distances.
(3) Switch off electricity whenever not required.
(4) Use power-saving devices.
(5) Check power equipment regularly.
(6) Clean gas burners regularly and switch off the gas regulator when not in use.
(7) Create awareness in the neighbourhood with catchy slogans.
(8) Make greater use of non-conventional sources of energy, as India has an abundance of sunlight, water, wind and biomass.
‘Energy saved is energy produced.’

Teacher's Note:
a) Eight points given — a mix of household habits and larger policy (non-conventional energy).
b) ‘Energy saved is energy produced’ is a quotable line worth using directly in an answer.

Question 9. ‘Minerals are an indispensable part of our lives.’ Support the statement with examples.
Answer:
(1) Minerals are an indispensable part of human life — almost all things we use are made of minerals.
(2) Human beings use minerals for their livelihood, decoration, festivities, and religious and ceremonial rites.
(3) Buildings, ships, railway lines and aeroplanes are manufactured from minerals and run on power resources derived from the earth.
(4) Our food also contains minerals; life processes cannot occur without them.
(5) Minerals make up only about 0.3% of our total nutrient intake, but they are so important that without them we would not be able to utilise the other 99.7% of the foodstuffs we eat.

Teacher's Note:
a) The 0.3% vs 99.7% figure is a striking, exam-friendly statistic worth remembering.
b) This overlaps with the earlier 'importance of minerals' question — combine for a fuller answer.

Question 10. Which is the most abundantly available fossil fuel in India? Assess the importance of its different forms.
Answer:
Coal is the most abundantly available fossil fuel in India, and the main source of power generation in the country.
(a) Lignite coal: the principal lignite reserves are in Neyveli, Tamil Nadu; used for generation of electricity.
(b) Bituminous coal: the most popular coal in commercial use. The major resources of metallurgical (Gondwana) coal are located in the Damodar valley (West Bengal, Jharkhand), Jharia, Raniganj and Bokaro.
(c) Anthracite: found only in Jammu and Kashmir; the highest quality hard coal.
(d) Tertiary coal occurs in the north-eastern states of Meghalaya, Assam, Arunachal Pradesh and Nagaland.

Teacher's Note:
a) Four forms of coal, each with a named region — Neyveli (lignite), Damodar valley (bituminous), J&K (anthracite), north-east (tertiary).
b) This is a frequently tested 'forms of coal with locations' question.

Question 11. What is the next major source of energy after coal in India? Describe any three advantages of it.
Answer:
The substitute source of energy after coal in India is petroleum. Main advantages of petroleum:
(1) It can be used as a fuel for heat and lighting.
(2) It can also be used as a lubricant for machinery and equipment.
(3) It can be used as a raw material for a number of manufacturing sectors, such as textiles, fertilisers and petrochemicals.

Teacher's Note:
a) Petroleum's three advantages span fuel use, lubrication, and raw-material use — cover all three for full marks.

Question 12. State any two factors which influence the formation of a mineral.
Answer:
(1) The formation of minerals depends on the physical and chemical conditions under which the material forms.
(2) Coal and some forms of iron ore have been concentrated as a result of long periods under great heat and pressure.
(3) In igneous and metamorphic rocks, minerals may occur in cracks, crevices, faults or joints, often formed when minerals in liquid/molten and gaseous forms are forced upward through cavities toward the earth's surface.

Teacher's Note:
a) Heat, pressure, and physical/chemical conditions are the three factors to recall.
b) This explains why minerals often occur along fault lines and rock cracks.

Question 13. How do geologists define minerals? Give one example each of the hardest and the softest minerals.
Answer:
(1) Geologists define minerals as a ‘homogeneous, naturally occurring substance with a definable internal structure’.
(2) Minerals are found in varied forms in nature.
(3) The hardest mineral is diamond, and the softest is talc.

Teacher's Note:
a) Learn this exact geologist's definition — it is sometimes asked for word-for-word.
b) Diamond/talc pairing reappears in the rocks-vs-minerals question above.

Question 14. What is the use of manganese ore? Where in our country do we have its deposits?
Answer:
Uses:
(1) Manganese is used for making steel; it gives strength to iron.
(2) It is also used in manufacturing bleaching powder, insecticides and paints.
Deposits of ore in India: manganese ore reserves exist in Karnataka, Odisha, Madhya Pradesh, Maharashtra and Goa.
India consumes nearly four-fifths (4/5) of its total manganese ore production domestically; the rest is exported, mostly to Japan.

Teacher's Note:
a) Manganese + iron = steel is the single most important fact here.
b) The 4/5 domestic consumption figure is a specific number worth remembering.

Question 15. Name the rock mineral which is the basic raw material for the cement industry. State its composition and use.
Answer:
(1) Limestone is the basic raw material for the cement industry.
(2) It is found in association with rocks composed of calcium carbonate, or calcium and magnesium carbonate.
(3) It is also used for smelting iron ore in the blast furnace.

Teacher's Note:
a) Limestone → cement is the key link; its second use in iron smelting is a less obvious but often-tested fact.

Question 16. Explain veins and lodes. Which minerals are found in them?
Answer:
In igneous and metamorphic rocks, minerals may occur in cracks, crevices, faults or joints. The smaller occurrences are called veins, and the larger ones are called lodes.

Teacher's Note:
a) Veins = smaller occurrences, lodes = larger occurrences — an easy one-line distinction to remember.
b) Both occur in igneous and metamorphic rocks specifically, not sedimentary rocks.

Question 17. ‘Aluminium is an important metal.’ Support the statement with examples.
Answer:
Aluminium is an important metal because:
(1) It is light in weight.
(2) It is resistant to corrosion.
(3) It is a good conductor of heat.
(4) It has great malleability.
(5) It is used to manufacture aircraft, utensils and wires.
(6) It is used as a substitute for copper, steel and zinc.

Teacher's Note:
a) Light weight + corrosion resistance are the two properties most often tested.
b) Aircraft manufacturing is the standout real-world application to cite.

Question 18. ‘Minerals found in ocean waters mostly are not of economic significance.’ Give one reason. Name any two minerals derived from ocean water.
Answer:
(1) Minerals found in ocean water mostly are not of economic significance because: (i) they are too widely diffused; (ii) there is a higher cost and environmental constraints involved in marine mining; (iii) mining is hampered by technological constraints, such as ocean depth.
(2) Minerals derived from ocean water include common salt, magnesium, bromine and manganese nodules.

Teacher's Note:
a) Common salt is the most familiar ocean-derived mineral to name first.
b) The reason is mainly economic (cost, technology) rather than the minerals being absent.

Teacher's Note:
a) Malleability and lustre are the two quickest tests to tell metallic and non-metallic minerals apart.
b) Note where each type occurs: metallic in igneous/metamorphic rocks, non-metallic in sedimentary rocks.

Teacher's Note:
a) Biogas is man-made and local; natural gas is a geological deposit found only in specific locations.
b) Biogas is a renewable resource since it's made continuously from waste; natural gas is non-renewable.