Question

Where do we get coal from and how is it formed? Name the process.

Answer 1

Hint: Carbon has a tendency to exist in its many allotropic forms. One of its important allotropic forms is coal which is an amorphous solid and hence is also termed as amorphous carbon. Some other examples of amorphous carbon are coke, soot and activated charcoal.

Complete answer: Coal is basically a fossil fuel which is obtained from the remains of prehistoric or primitive animals and plants. As it is a fossil fuel, its formation takes around millions of years and then is extracted via different methods.
Process of formation of coal:
Step-1: Peat:
It is the first stage for the formation of coal. It is in the form of an organic substance produced because of partial decomposition of dead matter.
Step-2: Lignite:
It is the second stage for the formation of coal. When the organic matter experiences the pressure exerted by sediments, then it forms a dark brown matter which consists of traces of plants.
Step-3: Bituminous coal.
It is the third stage for the formation of coal. It is formed when pressure is added to the dark brown matter which was obtained in step-2. It is also termed as soft coal.
Step-4: Anthracite coal:
It is the fourth stage for the formation of coal. When high pressure and high temperature is exerted on the soft coal, then the formation of hard coal or anthracite coal takes place.
Hence, the overall process involved in the formation of coal are peatification and coalification.

Note:
It is important to note that the anthracite coal is hard and lustrous and consists of the highest percentage of carbon among all the coal sources formed in the given four steps. Also, the process in which dead plants and animals convert into carbon is known as carbonization.