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2. USES - It is mainly used to generate heat and electricity. It is used in households and in industries to
accomplish various tasks. It is the cheapest source of power fuel. The iron and steel industry
depends heavily on fossil fuel for energy. It is also used to produce useful products such as coal tar
and coal gas.

3. PETROLEUM - Like coal , petroleum is also a fossil fuel that takes millions of years to form under the
earth crust. Petroleum is also known as the “BLACK GOLD” or the “crude oil”. Petroleum is formed
from the remains of dead plants and animals. When plants and animals die, they sink and settle on
the seabed.
4. FORMATION OF PETROLEUM: Millions of years ago, these dead wildlife and vegetation
decomposed and got mixed with sand and silt. Certain bacteria helped in the decomposition of this
organic matter and caused some chemical changes. The partially decomposed matter remained on
the seabed and eventually was covered with multiple layers of sand and silt. This burying took
millions of years, and finally, due to high temperature and pressure, the organic matter
decomposed completely and formed crude oil.
USES - Refined products obtained from crude oil have a number of uses.
1. Liquefied Petroleum Gas or LPG is used in households as well as in the industry.
2. Diesel and petrol are used as fuels for vehicles. Diesel is generally preferred for heavy motor
vehicles.
3. Petrol is also used as a solvent for dry cleaning, whereas diesel is also used to run electric
generators.
4. Kerosene is used as a fuel for stoves and jet planes.
5. Lubricating oil reduces wear and tear and corrosion of machines.
6. Paraffin wax is used to make candles, ointments, ink, crayons, etc.