What are fossil fuels ? State its disadvantages.

Explanation

Fossil fuels are the major energy source at present day because we continue to be largely dependent on fossil fuels for most of our energy requirements.
Plants and animals which got buried deep under the earth surface millions of years ago was converted into fuel due to excess heat and pressure. These are called fossil fuels.

The growing demand for energy was largely met by the fossil fuels - coal and petroleum.
Disadvantages : (1) Fossil fuels were formed over millions of years and they are only limited reserves.
(2) The fossil fuels are non-renewable sources of energy.
(3) Air pollution is caused by burning of coal or petroleum products. The oxides of carbon, nitrogen and sulphur that are released on burning fossil fuels are acidic oxides. These can lead to acid rain.
( 4) Carbon dioxide produced by burning of fossil fuels leads to greenhouse effects.