Question

The density of coal is ________ when compared to coke.
A) More
B) Less
C) Same
D) Can’t say anything

Answer 1

The term density is defined as the mass present per unit volume. The formation of coal is done by the incomplete combustion process of wood and whereas the coke is formed by the calcination process of mineral coal. One can use this data to predict the density of coal and coke.

Complete step by step answer:

1. First of all we will learn about the process of the formation of coal and coke one by one. The coal is formed over a long period of time when the dead plants and animals are trapped in the ground for millions of years and they turn into fossil fuel due to conditions such as high temperature and high pressure. Coal is a type of fossil fuel that is formed underground of the earth's surface. Coal is hard rock-like material and it does have many impurities such as sulfur, oxygen, and nitrogen elements. Due to coal being formed in conditions like high temperature and high pressure we can say that coal has a very high density.

2. Now let's learn about the coke which is formed by burning wood and oil and also coal in the absence of air. The coke is grey in color and very much porous solid than the coal. The coke is also made by the calcination or dry distillation process of mineral coal. The dry distillation process is generally used for organic material and it is performed in the absence of air and oxygen. Hence, coke is porous in nature and has less density than coal.

Therefore, the density of coal is more when compared to coke which shows option B as the correct choice.

Note:
The coal and coke can be easily differentiated based on their color and appearance. The coal is shiny black in color and is very hard in nature which doesn’t have any pores. The coke is dull in color which is grey colored and has a porous appearance. The coal emits smoke when it is burning while coke gives clean burning.