QUESTION ANSWERS OF CH MINERALS AND ENERGY RESOURCES

Chapter – 5 Minerals and Energy Resources.

Minerals:- A substance which is found in the earth’s crust and which generally has a definite chemical composition.

Mineral Ore: Mineral ore is the raw metal extracted from the earth mixed with soil and other impurities.

Mining: Mining is an economic activity of extracting minerals from the earth.

Fossil Fuels: These are fuels formed by the decomposition of organic under the earth or the sea bed.

Non-ferrous minerals: Minerals devoid of iron contents are termed as non-ferrous minerals eg., zinc and lead.

Ferrous minerals: These are metals which contain iron. Eg iron ore and manganese ore.

Thermal electricity: The electricity produced by using coal, petroleum or splitting atomic minerals in controlled condition.

 Veins and lodes: In igneous and metamorphic rocks minerals may occur in the cracks, crevices, faults or joints. The small occurrences are called the Veins and the larger ones are called the lodes.

Haematite: This is the most important industrial iron ore in terms of the quantity used. It contains about 60% to 70% of pure iron about.

Magnetite: This is the best quality of iron ore and contains about 72% iron. It has excellent magnetic qualities, especially valuable in the electrical industry.

Energy: The resources which are used for generating energy are known as energy resources. Coal, petroleum, uranium, etc. are some of the important energy resources.

Q. 1. What is H.B.J.?

Ans. It is a gas pipeline which links the Mumbai High and the Bassien with the fertilizer, power and industrial complexes in western and northern India.

Q .2. What are the two ways it to generate electricity?

Ans. Electricity is generated mainly in two ways: by running water which drives hydro turbines to generate hydro electricity; and by burning other fuels such as coal, petroleum and natural gas to drive turbines to produce thermal power

Q. 3 How is nuclear energy obtained?

Ans. Nuclear energy is obtained by altering the structure of atoms.

Q. 4. What is biogas?

Ans. Bio-gas is the energy obtained from the organic waste which is converted into energy by direct combustion or by conversion of such wastes into alcohol, methane or other storage fuels.

Q. 5. How is bauxite ore formed?

Ans. Bauxite ore is formed through the decomposition of surface rocks, and the removal of soluble constituents, leaving a residual mass of weathered material containing ores.

Q. 6. What is the importance of minerals?

Ans. Minerals are an indispensable part of our lives or for an economy because:

i). Everything we use, from a tiny pin to towering building or a bus, or a big ship, all are made from minerals.

ii). The country earns foreign exchange from the export of minerals.

iii). Mining and extraction of minerals provide employment to the people.

iv) Minerals like coat and petroleum are also the main sources of power.

Q. 7 How do minerals occur in igneous and metamorphic rocks?

Ans. Minerals generally occur in these forms: In igneous and metamorphic rocks, minerals may occur in the cracks, crevices, faults and joints. The smaller occurrences are called veins and the larger one are called the Iodes. In most of the cases, they are formed when minerals in liquid/molten and gaseous forms are forced upwards through cavities towards the earth’s surface. They cool and solidify as they rise. Major metallic minerals like tin, copper, zinc and lead etc. are obtained from veins and lodes.

Q. 8. How do minerals occur in sedimentary rocks?

Ans.

i). In sedimentary rocks, a number of minerals occur in beds or layers.

ii). They have been formed as a result of deposition, accumulation and concentration in horizontal stratas.

iii). Coal and some forms of iron ore have been concentration as a result of long periods under great heat and pressure.

iv) .Another group of sedimentary minerals include gypsum, potash, salt and sodium salt. These are formed as a result of evaporation especially in arid regions.

Q. 9.  What are the uses of aluminum?

Ans

i). It is used for making pots and pans because it a good conductor of heat.

ii). Aluminum also conducts electricity well and is used to make electrical wires. Aluminum is used to make cans and various beverages and other liquids.

iii). It can be pressed into a thin foil that is used both commercially and in homes for such purposes as wrapping foods for storage.

iv). Because, aluminum is light and strong, it is widely used in aeroplanes and spacecrafts. It can be made even stronger by mixing it with other metals to form same important alloys.

Q. 10. Explain the formation of petroleum in India?

Ans. Most of the petroleum occurrence in India are associated with anticlines and fault traps in the rock formation of the Tertiary age. In regions of the folding, anticlines or domes, it occurs were oil is trapped in the crest of the unfold. The oil bearing layer is a porous limestone or sandstone through which oil may flow. The foil is prevented from rising or sinking by the intervening non-porous layers.

Petroleum is also found in the fault traps between the porous and the non-porous rocks. Gas being lighter usually occurs above the oil.

Q.11. Distinguish between magnetite and haematite.

Ans. Magnetite

i). It is the finest iron ore with a very high content of iron upto 70%.

ii). It is the most important input in the electrical industry.

Haematite

i). It has slightly lower iron content than magnetite, i.e., 50-60%.

ii). It is the most important input in industrial iron ore.

Q. 12. What is gobar gas or biogas? State its three uses.

Ans.

i) It is an energy gas which is produced from the organic waste such as farm waste, shrubs, animals and human waste.

ii). It is a non-conventional source of energy.

iii). It has higher thermal efficiency in comparison to kerosene, cowdung, coal and charcoal.

iv) It does not cause any pollution.

Q. 13. What are non-conventional sources or energy? Why there is a pressing need to use these resources of energy?

Ans. These are the sources of energy which are renewable.

i). The growing consumption of energy has resulted in the country becoming increasingly dependent on fossil fuels such as coal, oil and 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.

Q. 14 What is solar energy? What is its importance?

Ans. The energy obtained from the sun is called the solar energy.

i). Solar energy is free of cost.

ii). It does not cause any pollution.

iii). It is a non-conventional source of energy.

iv). It will reduce the dependence of rural households on firewood and dune cakes.

Q.15 Difference between Conventional and Non- Conventional  Sources of Energy

Conventional Sources of Energy

I. The sources of energy which have been in use for a long time, e.g., coal, petroleum, natural gas and water power.

II. They are exhaust able except water.

III. They cause pollution when used, as they emit smoke and ash.

IV. They are very expensive to be maintained, stored and transmitted as they are carried over long distance through transmission grid and lines.

Non-Conventional Sources of Energy

I. The resources which are yet in the process of development over the past few years. It includes solar, wind, tidal, biogas, and biomass, geothermal.

II. They are inexhaustible.

III. They are generally pollution free.

IV. Less expensive due to local use and easy to maintain