Good morning children. Today, we shall learn about petroleum and its usage. Like coal, petroleum is also a fossil fuel, which means it is formed from the remains of dead organisms. However, it is liquid because the process of its formation was much different from the formation of coal. Petroleum was formed from the remains of sea creatures. As they died, their bodies settled at the bottom of the sea or ocean and gradually got covered by sand, clay, etc over millions of years. The absence of air, high temperature, and high pressure transformed the dead organisms into petroleum and natural gas. All of us know how important petrol, diesel, etc are. We get these fuels from petroleum. We also get kerosene from petroleum. Petroleum needs to be refined in the refineries to get these fuels. Raw petroleum or crude oil is a dark, oily liquid with an unpleasant smell. It is extracted from Earth's crust through a deep oil well. A huge pump extracts the petroleum through this deep oil well. Petroleum is a complex mixture. Petroleum refining means separating its components, and it is carried out at petroleum refineries. This separation process is known as fractional distillation. This process is actually for separating chemical components by their boiling point. The mixture is heated to a temperature at which one or more fractions of the compound will vaporize. Different components vaporize at different temperatures and thus get separated. So, we get lots of things from petroleum. We get fuels like petrol, kerosene, diesel, LPG, etc. We get lubricating oil. Paraffin wax, which we get from the residue of the refining process, is used for making ointments, candles, petroleum jelly, face cream, wax, etc. Bitumen, which is also obtained from the residue of the fractional distillation process, is used for making paint...