Question

The main constituent of coal is:
(A) Carbon
(B) Oxygen
(C) Air
(D) Water

Answer 1

Hint: Coal is a brown-black coloured combustible material which is mainly used as a fuel. Upon combustion (reaction with oxygen), coal gives carbon dioxide or carbon monoxide as major products.

Complete step by step answer:
We know that coal is a combustible material which is black in colour. Coal is used as a fuel.
- Coal is formed by decay of the dead plant matter which takes approximately millions of years. It is believed that that conversion is a result of heat and pressure.
- The coal can be characterized into many types depending upon the composition of carbon. The different types may include anthracite, peat, lignite, bituminous, etc.
- Here, we need to give the name of the element which is present in the highest amount.
- There are many elements present in coal. The element with highest % is carbon which makes up to 85% of bituminous coal composition. However, % of carbon may vary depending upon the type of coal but carbon still remains the most abundant element in its composition.
- Hydrogen, nitrogen, oxygen and sulphur are also present in coal but their amount is very low.
- Anthracite is a coal which is of highest rank and lignite is the lowest ranked coal.
Thus, we can conclude that the main constituent of coal is carbon.
So, the correct answer is “Option A”.

Note: Note that approximate amounts of carbon in anthracite, bituminous, lignite and peat (different types of coals) is 90%, 80%, 65%, <60% respectively. We can say that more the amount of carbon present in the coal, more heat it will give upon combustion.