Coal has been used as a main source of energy by human beings for centuries. It is formed millions of years ago by anaerobic digestion of remains of large plants that got buried in the earth due to earthquakes.
Occurance of Coal
Almost in every country big reserves of coal are present. In our country coal is found mainly in coal mines of Jharia and Bokaro in Bihar and Raniganj in West Bengal. In addition of it coal is also found in Orisa and Madhya Pradesh.
Composition of Coal
Coal consists of various types of substances such as carbon, hydrogen, oxygen, sulphur, nitrogen etc. however, the chief component of coal is carbon. The quality of coal depends on the percentage of carbon present in it. On the basis of difference of percentage of carbon, coal can be classified into four types. The variety of coal having lowest percentage of carbon is called peat. Peat consists of about 27% carbon. The variety of coal having highest percentage of carbon (95%) is anthracite. And the rest of two varieties of coal called lignite and bitumen contains about 35% and 80% of carbon respectively. Out of these four varieties of coal, anthracite is considered to be the most superior quality of coal.
Uses of Coal
When coal is burnt, it produces a large amount of energy in the form of heat and light. Due to these reasons coal is used;
1. in homes to cook food.
2. in industries for heating purpose.
3. in thermal power plants to generate electricity.
4. in the manufacture of coke, coal gas and coal tar.
Test Your Understanding and Answer These Questions:
- What is peat?
- What is anthracite?
- How coal is formed?
- Name the most superior quality of coal?
- Name the variety of coal having highest percentage of carbon?