Question

What is the main constituent of coal?
A) Hydrogen
B) Oxygen
C) Carbon
D) Nitrogen

Answer 1

Hint: The answer here is based upon the fact that coal is an allotrope of that element which is known for its highest number of allotropic forms and this fact gives you the correct answer.

Complete answer:
> In the lower classes of chemistry, we have dealt with the concepts in inorganic chemistry about isotopes, allotropes and their structures and also about the isomers.
> Now, let us refresh the topic that deals with the allotropic forms of several elements:
- Coal is the black coloured solid which is obtained by the fossil fuel and the precursor of this coal is called peat.
- Coal is an allotrope of the element which has more number of allotropes until now that is carbon.
- Along with carbon, coal there are variable amounts of other elements also chiefly hydrogen, sulphur and oxygen.
- But the main composition of coal is carbon and some parts are of lignite.
- Coal is mainly used as a source of energy which is mainly employed in the industrial process to convert water into steam which drives the turbine.

Therefore, based on all these facts about coal, we can say that the correct answer is option C) Carbon.

Note: Note that peat that is precursor of coal are accumulated in wet swampy environments which is known as mires and thus is obtained naturally and coal is said to be about 100 million years old and also note that sub – bituminous coal is also called as ‘brown coal’ along with lignite.