Question

Which coal is also known as soft coke?
A. Anthracite coal
B. Bituminous coal
C. Lignite coal
D. Both B and C

Answer 1

Hint: Bituminous coal and lignite coal, both are relatively soft coal. Bituminous is higher quality coal than lignite but of poorer quality than anthracite.

Complete Answer: Decayed plant matter over millions of years formed a black or brownish-black colored substance which is known as Coal and the process is known as coalification. Carbon is the major element found in coal with variable amounts of other elements like hydrogen, sulfur, oxygen, and nitrogen. The occurrence of Coal is generally from that place which was included in Earth’s tropical area earlier. Most of the vast industries use coal as a fuel for a long time. Both extraction and use of coal are hazardous to the environment. The grade of coal produced depends on the pressure and temperature under which coalification occurred. Different types of coals are as follow:
1. Anthracite coal contains 80 to 95 percent carbon in it along with very little volatile matter. It is considered to be the coal of the best quality due to high efficient burning of anthracite coal as it ignites slowly and burns with a nice short blue flame. This type of coal is found only in Jammu and Kashmir in India.
2. Bituminous coal contains 40 to 80 percent carbon in it with 15 to 40 percent volatile matter. This is the most widely used and also the most widely available type of coal. This coal does not have traces of original vegetable material. These are also known as soft coal.
3. Lignite contains about 40 to 55 percent carbon in it with a high moisture content of about 35 percent. It is lower grade coal due to less concentration of carbon present in it. It causes fire accidents several times in mines due to spontaneous combustion which makes its usage a non-efficient manner. This is also known as brown coal.

Thus, the correct option is D. Both Bituminous and lignite coal are soft coal and anthracite is hard coal.

Note: China is the largest consumer and importer of coal across the world. Coke is a fuel that is obtained from the calcinations or dry distillation of mineral coal. It is too composed of carbon and has a high calorific value but its combustion is highly polluting.