NCERT Gist: Coal And Petroleum | Additional Study Material for UPSC PDF Download

- These were formed from the dead remains of living organisms (fossils) known as fossil fuels.
- Coal: It is as hard as stone and is black in colour. Under high pressure and high temperature, dead plants got slowly converted to coal.
- As coal contains mainly carbon, the slow process of conversion of dead vegetation into coal is called carbonisation.
- Since it was formed from the remains of vegetation, coal is also called a fossil fuel.
- Coke: a tough, porous and black substance.
- It is almost pure form of carbon.
- Coke is used in the manufacture of steel and in the extraction of many metals.
- Coal tar is a black, thick liquid with unpleasant smell. It is a mixture of Products obtained from coal tar are used as starting materials for manufacturing various substances used in everyday life and in industry, like synthetic dyes, drugs, explosives, perfumes, plastics, paints, photographic materials, roofing materials, etc.
- Interestingly, naphthalene balls used to repel moths and other insects are also obtained from coal tar.
- These days, bitumen, a petroleum product, is used in place of coal-tar for metalling the roads.
- Coal gas was used for street lighting for the first time in London in 1810 and in New York around 1820.
- Now days, it is used as a source of heat rather than light.
- Petroleum was formed from organisms living in the sea.
- As these organisms died, their bodies settled at the bottom of the sea and got covered with layers of sand and clay.
- Over millions of years, absence of air, high temperature and high pressure transformed the dead organisms into petroleum and natural gas.
- The layer containing petroleum oil and gas is above that of water because the layer containing petroleum oil and gas is above that of water.
- Petroleum is a dark oily liquid.
- In India, the Petroleum Conservation Research Association (PCRA) advises people how to save petrol/diesel while driving.