Q.1. “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. [CBSE 2019, 32/ 2/ 3]
Ans. Another problem with fossil fuels is that they are steadily increasing air pollution, their use is linked to global warming. So, it is important that we use fuels only when it is absolutely necessary. Tri this way, we can save these fuels for the Manufacture of many substances which are dependent on petrochemicals.
For energy purpose, we need to look for alternative sources, such as solar energy, tidal energy, wind energy, etc. Furthermore, fossil fuels will be available to future generations for more useful products. In India, the Petroleum Conservation Research Association (PCRA) offers the following tips to conserve petrol and diesel while driving. Furthermore, fossil fuels will be available to future generations for more useful products.
(i) Drive at a constant and moderate speed as far as possible. Driving at a high speed or slow speed wastes a lot of fuel.
(ii) Switch of engine if you have to wait at traffic lights or for any other reason.
(iii) Check the tyre pressure regularly, low pressure or too high pressure waste fuel.
(iv) Make sure that you send your vehicle to garage for regular maintenance
Q.2. Name the best variety of iron-ore found in India. [CBSP (AI) 2017]
Ans. Best variety of Iron Ore in India : Magnetite
Q.3. How do minerals occur in igneous and metamorphic rocks? [CBSE Delhi 2016, CBSE (AI) 2017]
Ans. Occurrence of minerals: In igneous and metamorphic rocks minerals may occur in cracks, crevices, faults and joints
Q.4. Differentiate between ferrous and non-ferrous minerals, with examples. [CBSE (F) 2017]
Ans. Difference between ferrous and non ferrous minerals:
Q.5. Describe any three characteristics of ‘Odisha-Jharkhand belt’ of iron ore in India. [CBSE Delhi 2017]
Ans. Odisha- Jharkhand Belt:
(i) In Odisha high grade hematite ore is found.
(ii) It is found in Badampahar mines in the Mayurbhauj and Kendujhar districts.
(iii) In the adjoining Singbhum district of Jharkhand hematite iron ore is mined in Gua and Noamundi.
Q.6. Describe any three characteristics of Bellary-Chitradurga, Chikmaglur-Tumkur iron-ore belt in India. [CBSE (F) 2017]
Ans. Durg-Bastar-Chandrapur Belt It lies in Chhattisgarh and Maharashtra.
(i) Very high grade hematites are found in the famous Bailadila range of hills in the B as tar district of Chattisgarh.
(ii) The range of hills comprises of 14 deposits of super high grade hematite iron ore.
(iii) It has the best physical properties needed for steel making. Iron ore from these mines is exported to Japan and South Korea via Vishakhapatnam port.
Q.7. Which State is the largest producer of manganese in India ? Mention any two uses of manganese. [CBSE (Comp) 2017]
Ans. Odisha is the largest producer of manganese: Uses of manganese in India:
1. It is used in manufacturing of steel and ferro- manganese alloy.
2. These alloys are strong and are used in making giant machines.
3. It is also used in manufacturing bleaching powder.
4. It is also used in insecticides.
5. It is also used in manufacturing of paints.
Q.8. ‘Natural gas is an important source of clean energy’. Support the statement with examples. [CBSE Sample Question 2017]
Ans. Natural gas
In a power deficient country, natural gas is a precious gift.
(i) It can be used as a source of energy. It takes less time to build a power plant based on natural gas.
(ii) It can be used as an industrial raw material in petro-chemical industry.
(iii) It can be used in building the fertilizer plants and thereby encouraging the use of fertilizers. It can boost agricultural production.
(iv) Through easy transportation of pipelines, its utility is further increased
(v) Use of Compressed Natural Gas (CNG) for vehicles to replace liquid fuels is gaining wide popularity in the country.
Q.9. Discuss the hazards of mining on the life of miners and on environment. [CBSE Sample Question 2017]
Ans. (i) The dust and noxious fumes inhaled by miners make them vulnerable to pulmonary diseases.
(ii) The risk of collapsing mine roofs, inundation and fires in coalmines are a constant threat to miners.
(iii) The water sources in the region get contaminated due to mining. Dumping of waste and slurry leads to degradation of land, soil and increase in stream and river pollution.
Q.10. How we have to adopt a cautious approach for the judicious use of our limited energy resources? Explain. [CBSE (Comp) 2017]
Ans. Steps to adopt for judicious use of our limited energy resources :
1. Use public transport.
2. Switch off electricity when not in use.
3. Use power saving devices.
4. Use non conventional sources of energy.
Q.11. Why do we need energy?
Why is energy needed? Write one reason. [CBSE (Comptt.) 2017]
Ans. (i) It is needed to cook, to provide light and heat.
(ii) To propel vehicles.
(iii) To drive machinery in industries.
Q.12. Why should we use renewable energy resources ? Explain with arguments. [CBSE (F) 2017]
Ans. We should use renewable energy resources because of the:
(i) Exhaustibility of non renewable resources.
(ii) Long years of geological formation of non renewable resources.
(iii) Causes less polludon.
(iv) Available in abundance.
(v) Environmental friendly.
(vi) Strong dependence on fossil fuels such as coal, oil and gas is a threat to our environment.
(vii) Rising prices of oil and gas and their potential shortages.
(viii) Uncertainties about the security of energy supply in future.
(ix) There is a pressing need to use renewable energy sources like solar energy, wind, tide;, biomass and energy from waste material.
Q.13. “India is fortunate to have fairly rich and varied mineral resources. However, these are unevenly distributed.” Comment.
“Minerals are unevenly distributed in India.” Support the statement with examples. [CBSE (Al) 2017]
Q.14. “Minerals are indispensable part of our lives.” Support this statement with suitable examples. [CBSE (F) 2016, CBSE (Comp) 2017]
Ans. Minerals are indispensable part of our lives:
(i) Almost everything we use, from a tiny pin to a towering building or a big ship, all are made from minerals.
(ii) The railway lines and tarmac (paving) of the roads are made from minerals.
(iii) Cars, buses, trains, aeroplanes are manufactured from minerals and run on power resources derived from the earth.
(iv) Even the food that we eat contains minerals.
(v) In all stages of development, human beings have used minerals for their livelihood, decoration, festivities, religions and ceremonial rites.
Q.15. Why is Conservation of mineral resources essential? Explain any three methods to conserve them. [CBSE 2015]
Why is it necessary to conserve mineral resources ? Explain any four ways to conserve mineral resources. [CBSE (AI) 2017]
Ans. Need for conservation of Minerals:
(i) We are rapidly consuming mineral resources that require millions of years to be created and concentrated.
(ii) The geological processes of mineral formation are so slow that the rates of replenishment are infinitely small in comparison to its consumption.
(iii) Continued extraction of ores leads to increasing costs as minerals extraction comes from greater depths along with decrease in quality.
(iv) Most of the minerals are unevenly distributed on the Earth’s surface.
Mineral resources are therefore finite and non-renewable.
Three methods to conserve Minerals:
(i) We must make use of minerals in a planned and sustainable manner.
(ii) Improved technologies need to be constantly evolved to allow the use of low grade ores at low cost.
(iii) Recycling of metals.
(iv) Using scrap metals and other substitutes are steps in conserving ore mineral resources for the future.
Q.16. Answer the following in about 30 words.
(i) Distinguish between the following.
(a) Ferrous and non-ferrous minerals [CBSF. (F) 2017]
(b) Conventional and non-conventional sources of energy
Ans. (a) Ferrous minerals are in the category of metallic minerals that contain iron (Fe). The composition of iron varies from mineral to mineral. Pyrite is an example of ferrous mineral. Non-ferrous minerals arc the metallic minerals that do not contain iron (Fc). Gold (Au) is an example of non-ferrous mineral.
(ii) What is a Mineral?
Ans. Minerals are defined as solid, inorganic, naturally occurring substances with a definite chemical formula and general atomic structure.
(iii) How are minerals formed in igneous and metamorphic rocks? [CBSE (AI) 2017]
Ans. Minerals generally occur in igneous and metamorphic rocks. In most cases, they are formed when minerals in liquid or molten and gaseous forms are forced upward through cavities towards the earth’s surface, they cool and solidify as they rise in the cracks, crevices, faults or joints. The smaller occurrences are called veins and the larger are called lodes.
(iv) Why do we need to conserve mineral resources?
Ans. (i) Mineral resources form about 1% of Earth’s crust and require millions of years to form, therefore are finite and non-renewable in nature.
(ii) The continued extraction of ores will lead to increase in cost as extraction comes from greater depths.
(iii) There is also a decrease in quality along lower depths
Q.16. ‘Why is there a pressing need to use renewable energy resources in India. Explain giving any five reasons. [CBSE (Comptt) 2017]
Ans. (i) The growing consumption of energy has resulted in the country becoming increasingly dependent on fossil fuels such as coal, oil & gas.
(ii) Rising prices of oil and gas and their potential shortages have raised uncertainties about the security of energy supply in future, which in turn has serious repercussions on the growth of the national economy.
(iii) Moreover, increasing use of fossil fuels also causes serious environmental problems*
(iv) Hence, there is a pressing need to use renewable energy sources like solar energy, wind, tidal, biomass and energy from waste material. These are called non-conventional energy resources.
Q.17. “Energy saved is energy produced.” Justify the statement by giving any six measures to conserve the energy resources. [CBSE (Delhi) 2017]
Ans. We have to adopt a cautious approach for the judicious use of our limited energy resources.
As concerned citizens, we can do our bit by:
(i) Using public transport systems instead of individual vehicles.
(ii) Switching off electricity when not in use.
(iii) Using power saving devices like stars appearing in electronic industries.
(iv) Using CNG as fuel which is environmental friendly.
(v) Increased use of renewable energy.
(vi) Using of biogas for domestic consumption in the rural areas.
(vii) Using non-conventional sources of energy.
Q.18. Why is copper mainly used in electrical cables and electronic industries? [CBSE Sample Paper 2016]
Ans. Copper is mainly used because of being malleable, ductile and a good conductor of heat and electricity.
Q.19. Why are there a wide range of colours, hardness, crystal forms, lustre and density found in minerals? [CBSE Delhi 2016]
Ans. The ranges found in minerals are due to: Physical and Chemical conditions.
Q.20. Why should the use of cattle cake as fuel be discouraged? [CBSE (AI) 2016]
Ans. (i) It creates pollution.
(ii) It consumes most valuable manure which could be used in agriculture.
Q.21. How are ‘Gobar gas plants1 beneficial to the farmers? [CBSE (AI) 2016]
Ans. ‘Gobar Gas Plants’ are beneficial to the farmers in the form of energy and improved quality of manure.
Q.22. Give a short account of the major iron ore belts in India. [CBSE Sample Question 2016]
Ans. (i) Odisha-Jharkhand Belt In Odisha, high grade haematite ore is found in Badampahar mines in the Mayurbhanj and Kendujhar districts. In the adjoining Singhbhum district of Jharkhand, haematite iron ore is mined in Gua and Noamundi.
(ii) Durg-Bastar-Chandrapur Belt Tt lies in Ghhattisgarh and Maharashtra. Very high grade haematite are found in the famous Bailadila range of hills in the Bastar district of Chhattisgarh. It has the best physical properties needed for steel making; iron ore from these mines is exported to Japan, South Korea via the Vishakhapatnam port.
(iii) Bellary-Chitradurga-Belt Chikkamagaluru: Tumakuru belt in Karnataka has large reserves of iron ore. The Kudermukh mines located in the western ghats of Karnataka are a 100 per cent export unit. Kudermukh deposits are known to be one of the largest in the world.
(iv) Maharashtra-Goa belt It includes the state of Goa and RaLnagiri district of Maharashtra. Though the ores are not of very high quality, yet they are efficiently exploited. Iron ore is exported through the Marmagao port.
Q.23. ‘Consumption of energy in all forms has been rising all over the country. There is an urgent need to develop a sustainable path of energy development and energy saving’. Suggest and explain any three measures to solve this burning problem. [CBSE (AI) 2016]
There is an urgent need to develop a sustainable path of energy development. Give two broad measures for it. As concerned citizens, how can you help to conserve energy? [CBSE Sample Question 2016]
Ans. (i) “Consumption of energy in all forms has been rising all over the country. There is an urgent need to develop a sustainable path of energy development and energy saving.”
(ii) Energy sector of the National economy, agriculture, industry, transport, commercial and domestic needs input of energy.
(iii) With increasing population and changing lifestyles, energy consumption is increasing very fast.
(iv) We are not self sufficient in energy according to demands therefore judicious use of limited resources is essential.
Three measures to solve this burning problems are:
(i) We can do one bit by using public transport systems instead of individual vehicle.
(ii) Switching off electricity when not in use.
(iii) Using power saving devices or using non-conventional sources of energy.
(iv) Checking the power equipments regularly can help in saving of energy.
Q.24. “India is an important iron and steel producing country in the world. Yet we are not able to perform to our full potential.” Suggest and explain any three measures to get full potential. [CBSE (F) 2016]
Ans. India is an important iron and steel producing country in the world yet, we are not able to perform to our full potential largely due to:
(i) High costs and limited availability of coking coal.
(ii) Lower productivity of labour.
(iii) Irregular supply of energy, and
(iv) Poor infrastructure.
Q.25. How do minerals occur in sedimentary rocks? [CBSE Delhi 2016]
Ans. Occurrence of minerals in sedimentary rocks: In sedimentary rocks, a number of minerals occur in beds or layers. They have been formed as a result of deposition, accumulation and concentration in horizontal strata.
Q.26. Highlight the importance of petroleum. Explain the occurrence of petroleum in India. [CBSE Delhi 2016]
Ans. Importance of Petroleum:
(i) Petroleum is the major energy source in India.
(ii) Provides fuel for heat and lighting.
(iii) Provides lubricant for machinery.
(iv) Provides raw material for a number of manufacturing industries.
(v) Petroleum refineries act as nodal industry for synthetic, textile, fertilizer and chemical industries.
Q.27. Explain the importance of conservation of minerals. Highlight any three measures to conserve them. [CBSE (AI) 2016]
Ans. Importance of conservation of Minerals:
(i) Mineral resources are being rapidly consumed which takes millions of years to be created and concentrated.
(ii) Mineral resources are finite and non-renewable
(iii) Continued extraction of ores leads to increasing costs as mineral extraction comes from greater depths along with decreasing quality.
The three measures to conserve minerals are:
(i) It should be used in a planned a sustainable manner.
(ii) Improved technology needs to be constantly evolved to allow use of low grade ores at low costs.
(iii) Some of the metals are recyclables.
(iv) Scrap of metal can be used and some other substitute can be found.
Q.28. How is mining activity injurious to the health of the miners and environment? Explain. [O.RS.E, 2015]
What are the hazards of mining?
Ans. (i) The dust an d various fumes inhaled by miners make them vulnerable to pulmonary diseases.
(ii) The risk of collapsing mine roofs, inundation and fires in coal mines are a constant threat to miners.
(iii) The water resources in the regions get contaminated due to mining.
(iv) Dumping of waste and slurry leads to degradation of land, soil and increase in stream and river pollution.
Q.29. Which rock consists of single mineral only ? [CBSE 2015]