Question

Which coal contains most of the moisture content?
A. Anthracite
B. Bituminous
C. Lignite
D. Peat

Answer 1

Hint: Coal is a type of fossil fuel that can also be burned. It is a type of hard sedimentary rock that mostly consists of carbon and also hydrogen, oxygen, and nitrogen.

Complete step-by-step solution:
Anthracite, bituminous, sub-bituminous, and lignite are the four major types of coal. It is a sedimentary rock formed from peat, by the action of pressure of rocks laid down later on top. Bituminous coal has $45\mathrm{\%}\text{ - }86\mathrm{\%}$ of carbon. Lignite is often referred to as brown coal as it is soft, brown, and combustible. It relatively has low heat content and around $25\mathrm{\%}\text{ - }35\mathrm{\%}$ of carbon is present in it. It is used as a fuel for the steam – electric power generation and is mined all over the world. Its energy content ranges from 10 to 20 MJ per kg. Volatile matter is high in content in lignite which makes it easier to convert into gas and liquid petroleum products than higher-ranking coals. It can cause problems in transportation and storage due to its high moisture content and susceptibility to spontaneous combustion. Xyloid lignite or fossil wood and compact lignite or perfect lignite are the two categories into which lignite can be divided. Lignite has a high inherent moisture content of about 75% and an ash content ranging from $6\mathrm{\%}\text{ - }19\mathrm{\%}$.

Thus, option (C) is correct.

Note: In the United States, bituminous coal is between 100 million to 300 million years old. The coal which is most harmful to human health is lignite as its firing results in the emission of dust, Sulphur dioxide, and nitrogen oxides.