These DAV Class 8 SST Notes and DAV Class 8 SST Chapter 4 Notes – Mineral and Energy Resources hold significant importance as study material for students.
Mineral and Energy Resources Class 8 DAV Notes
→ Mineral and energy resources provide the foundation for economic and industrial development. No country can prosper without utilising its mineral and energy resources.
→ Minerals are natural chemical compounds, uniform in structure and composition. They are obtained from rocks having one or more minerals.
→ Minerals are extracted from mines only if the concentration of a particular mineral is high and it is commercially viable and useful.
→ Minerals are classified on the basis of their properties- metallic, non-metallic and mineral fuels.
→ Metallic minerals are of two types- ferrous and non-ferrous. Ferrous minerals contain iron and non-ferrous contain metals other than iron.
→ Non-metallic minerals do not contain metals. Generally they contain building materials such as sandstone, granite etc., gems such as diamond, topaz, etc. and other like mica, sulphur, salt, etc.
→ Mineral fuels are used as sources of energy. They are obtained from sedimentary rocks. They consist of coal (solid), petroleum (liquid) and natural gas (gaseous).
→ Iron, bauxite, copper, etc. are some of the important minerals. Iron is the backbone of modern civilization. Bauxite is used in the manufacturing of electric wires, aeroplanes, spare parts of vehicles, etc. Copper is widely used in electric goods.
→ Minerals are non-renewable resources. They are limited and unevenly distributed. Therefore, they should be conserved for future generations.
→ Energy is essential for everything. The different ways to obtain energy are through sun, fire, electricity or burning of fossil fuels. Energy is fundamental to the quality of our lives. We cannot imagine a comfortable life without it.
→ There are two types of energy resources- conventional sources and non-conventional sources.
→ Conventional sources include coal, petroleum, natural gas, thermal energy and hydro-electricity. These are non-renewable resources.
→ Non-conventional sources include solar energy, wind energy, geothermal energy, nuclear energy, tidal energy and biogas. These are renewable sources and do not have adverse effect on the environment.
→ Coal is widely used in iron and steel industry and thermal power stations. Petroleum or mineral oil is used as a source of power. Patrol, diesel, kerosene oil are the by-products of petroleum.
→ Solar energy is the greatest source of unlimited energy. In the tropical zone, it can be tapped to get maximum output.
→ In the areas of high wind velocity, wind is used to generate energy. Coastal areas are ideal for it.
→ Biogas is an excellent fuel for cooking, and lighting and produces huge amount of organic manure.
→ It is essential to conserve energy resources because of their rapid depletion and very slow regeneration of the exhaustible sources of energy like coal, petroleum and natural gas.
→ Mineral: A naturally occurring substance having a definite chemical composition.
→ Ore: A rock from which minearls are mined.
→ Metallic minerals: Minerals that contain metal
→ Non-metallic minerals: Minerals that do not contain metals. Instead they contain impure compounds or mineral fuels.
→ Rock: A mixture of one or more minerals.
→ Mining: Process of extraction or taking out minerals from rocks under the earth’s surface.
→ Alloy: A mixture of two or more metals.
→ Smelting: Process done to remove the impurities from the metallic ore.
→ Ferrous minerals: Minerals that contain iron as a constituent.
→ Non-ferrous minerals: Minerals that do not contain iron as a constituent.
→ Extraction: The process of taking out minerals from under the earth’s surface so that useful materials can be derived from them.
→ Thermal power: The electricity obtained from coal.
→ Hydel power: The energy possessed by river water or rain water falling from great heights.
→ Solar energy: The heat and light energy captured from the sun.
→ Wind energy: The energy possessed by moving air.
→ Biogas: A gaseous fuel obtained from the decomposition of organic waste like dead plant and animal material or animal dung and kitchen waste.