Describe the process of coal formation.

Coal was formed by the decomposition of large land plants and trees buried under the earth 300 million years ago.About 300 million years ago,the earth had dense forest s in low-lying wet land areas.Due to natural processes like earthquake,volcanoes and floods etc these forests were buried under the surface of earth.As more soil deposited over them,they were compressed.The temperature also rose as they sank deeper and deeper.Due to high pressure and temperature inside the earth,and in the absence of air,the woods of buried trees was slowly converted into soil.

The slow process by which the dead plants buried deep under the earth have become coal is called Carbonisation.Since coal was formed from remains of plants therefore coal is called a fossil fuel.

When heated in air,coal burns and produce,mainly carbon dioxide gas.A lot of heat energy is also produced during the burning of coal.

Coal is an important because it can be used as a source of heat energy as such,or it can be converted into other forms of energy such as coal gas,coke or electricity.