Class -8 Chapter- 3 coal and petroleum part -2 complete

complete pdf on telegram telegram link- https://t.me/akstyl123 📖 Chapter: Coal and Petroleum (Class 8 Science) 🌍 Natural Resources Natural resources: Resources that are obtained from nature. Inexhaustible resources: Unlimited, never run out (e.g., air, sunlight, water). Exhaustible resources: Limited, can finish if overused (e.g., coal, petroleum, natural gas). --- 🪨 Coal What is coal? A fossil fuel formed from dead plants buried under the earth millions of years ago. Formation of coal: Dead plants → buried under soil → heat and pressure → slowly converted into coal. This slow process is called carbonisation. Uses of coal: Fuel for cooking. Used in thermal power plants. In industries like cement, paper, and steel. Products obtained from coal: Coke: Tough, porous, almost pure carbon. Coal tar: Black liquid; used in making dyes, drugs, paints. Coal gas: Used as fuel. --- 🛢️ Petroleum What is petroleum? A dark, oily liquid found deep inside the earth, made from dead sea organisms. Formation of petroleum: Dead marine organisms → buried under mud → heat and pressure for millions of years → petroleum and natural gas. Petroleum Refining: Process of separating petroleum into useful products. Done in an oil refinery. Products obtained from petroleum: Petrol: Motor fuel. Diesel: Fuel for heavy vehicles. Kerosene: Cooking and lighting. Paraffin wax: Making candles, ointments. Lubricating oil: For machines. Bitumen: Road surfacing. --- ⚠️ Why Conserve Fossil Fuels? They are exhaustible. It takes millions of years to form. Use them wisely to avoid energy shortage in the future. --- 📌 Key Definitions: Fossil fuels: Fuels formed from the remains of dead plants and animals (e.g., coal, petroleum, natural gas). Carbonisation: Process of converting dead vegetation into coal due to heat and pressure. Petroleum refining: Separating crude petroleum into useful substances.