The natural sources of hydrocarbons include coal,petroleum and natural gas. These are often known as fossile fuel because they are the remains of animals and plants which are dead long millions years ago, this remains has become deposited and transformed into sediment as a result of the great heat and pressure in the earth crust. They are used as fuels, that is burnt to release heat and other forms of energy. Coal is a solid fuel, petroleum is a dark and viscous liquid fuel, otherwise called crude oil. While natural gas is a gaseous fuel.
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The natural sources of hydrocarbons include [[coal]], petroleum and natural gas. These are often known as fossile fuel because they are the remains of animals and plants which are dead long millions years ago, this remains has become deposited and transformed into sediment as a result of the great heat and pressure in the earth crust. They are used as fuels, that is burnt to release heat and other forms of energy. Coal is a solid fuel, petroleum is a dark and viscous liquid fuel, otherwise called crude oil. While natural gas is a gaseous fuel.