Read the passage given below and answer the questions that follow:

Coal is formed from the decomposed remains of plants that remained buried under high heat and pressure over millions of years under beds of sedimentary rocks. This inflammable organic substance is rich in carbon. It produces huge quantities of heat when burnt. Coal has been therefore the source of power in steam engines for long. Since the Industrial Revolution in the 18th century, coal is also used in the generation of electric power. In the early 20th century, as the steel industries were run on coal fired furnaces, they were, therefore, primarily located near coal mines. The thermal power stations used coal to generate electricity, which was supplied to domestic and industrial sectors. Thus, coal, also called the black gold, came to be the backbone of industrial growth.

1. How is coal formed?
2. Which property of coal is very useful in running steam engines?
3. Why were steel industries located near coal mines?
4. What is coal also known as? Why do you think it was so called?

1. Coal is formed from the decomposed remains of plants that remained buried under high heat and pressure over millions of years under beds of sedimentary rocks.

2. Coal is an inflammable organic substance which is rich in carbon. It produces huge quantities of heat when burnt. Coal has been therefore the source of power in steam engines for long.

3. In the early 20th century, as the steel industries were run on coal fired furnaces, they were, therefore, primarily located near coal mines.

4. Coal is also known as black gold as it became the backbone of industrial growth. Its importance in powering steam engines, producing a lot of heat energy when burnt, generating electricity, and supporting industries like steel gave it great economic value, just like gold.