Question

The density of coal is _________ when compared to coke.
A.Less
B.More
C.Equal
D.None of these

Answer 1

Hint: The measure of mass per unit volume is known as density. The density basically depicts the porosity of the material. The porous materials have low density and non - porous materials have high density.

Complete step by step answer:
When the remains of plants and animals live under the ground for millions of years then they are converted into fossil fuels due to high temperature, high pressure and the tough conditions of the earth’s crust. Fossil fuels include coal, petroleum, natural gas, oil and many more energy producing materials.
So we can say that coal is a fossil fuel. Basically it is a hard rock material, some impurities like sulphur, nitrogen and oxygen are seen when it is extracted. It is very hard solid with high density.
A grey, hard and porous substance derived from the burning of coal and oil in absence of air is known as coke. It is made up of high carbon contents and few impurities are also seen. It is derived from coke and oil with the help of a destructive distillation process (decomposition of unprocessed material by heating it to a high temperature is known as destructive distillation process). Destructive distillation process is usually used for organic materials and it works in absence of air and limited supply of oxygen.
So, due to the destructive distillation process the coke is porous and hence the density of the coke is low as compared to other carbon materials.
The density of coal is more when compared to coke.

So, the correct answer is Option B .

Note:
The basic difference between coal and coke is based on their burning capability. Coal is a shiny black fuel which emits smoke during burning and has low efficiency while coke is a dull black coloured byproduct of coke which burns cleaner and hotter than coal.