For more such informative content, go to https://scifitechify.blogspot.com/. This presentation has all topics of coal and petroleum covered. It talks about their real-world uses and application in electricity generation, automobile, fuel etc. It also talks about the disadvantages of using fossil fuels. It promotes sustainable and renewable energy sources over conventional fossil fuels. It also talks about hydrogen being the cleanest fuel and mixing with petrol.

1. L.3 Coal and Petroleum Gr 8 CBSE
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2. Natural Resources
● Inexhaustible Natural Resources
These resources are present in unlimited quantity in
nature and not likely to be exhausted by human activities.
eg: Sunlight, Air
● Exhaustible Natural Resources
The amount of these resources in nature is limited. They
can be exhausted by human activities.
eg: Forest, wildlife, minerals, coal, petroleum, natural gas
etc.

3. Fossil fuels
Exhaustible natural resources like coal, petroleum and natural
gas, are formed from the dead remains of living organisms
(fossils). They are also known as fossil fuels.
Coal - Formation
Process of conversion of wood into coal is called carbonisation.

4. Formation of coal
● About 300 million years ago the earth had dense forests
in low lying wetland areas. Due to natural processes,
like flooding, these forest got buried under the soil.
● As more soil got deposited on them they were
compressed. The temperature also rose as they sank
deeper and deeper.
● Under high temperature and high pressure, the dead
plants got slowly converted into coal.
● Coal mainly contains carbon and the slow process of
conversion of dead vegetation into coal is called
carbonisation.

6. Carbon content in different varieties of coal
● Peat - It is light brown spongy material and contains 55-
65% carbon. It is the most inferior variety of coal.
● Lignite - Soft brown coal and contains 65-75% Carbon.
● Bituminous - It is black in colour and is the most
commonly found variety of coal.It has 75-90% carbon. It
is used as household fuel and in Industries.
● Anthracite - It is hard black and contains upto 90%
carbon. It burns slowly with very little smoke.
Peat Lignite Bituminous Anthracite

7. Uses of coal
● It is one of the fuels used to cook food.
● It is used to manufacture coke, coal tar and coal gas.
● It is used used in thermal power plants to produce
electricity.
● It is used in the extraction of metals from their ores.
● Earlier it was used to produce steam to run steam
engines

8. Useful products from coal
● Coke - It is a tough, porous and black solid
obtained by the distillation of bituminous
variety of coal.
● It contains mainly carbon. It is used as Industrial fuel
and also in the extraction of iron from iron oxide in a
blast furnace.
● It is also used in the extraction of many metals.
● Coal tar - It is a black, thick liquid with an
unpleasant smell.
● Distillation of coal tar gives fractions like benzene,
toluene, xylene etc which are known as coal tar
crudes.

9. ● They form the starting material for the synthesis of dyes,
drugs, perfumes, explosives, preservatives, paints,
plastics etc.
● Naphthalene balls used to repel moth and other insects
are obtained from coal tar. Now a days bitumen, a
petroleum product, is used in place of coal tar for
metalling the roads.
● Coal gas - It is obtained during the processing of coal
to get coke. It is used in many industries situated near
the coal processing plant. It was used for street
lightning in London and New york in the early 19th
century and also as a source of fuel for domestic
purpose.

11. Petroleum
● It is derived from the Latin word (Petra - Rock and
Oleum -Oil)
● It is found deep inside the earth between layers of
porous and non porous rocks.
● Petroleum is a dark viscous, fluorescent and oily liquid
with an unpleasant odour.
● It is a mixture of hydrocarbons and cannot be used for
any purpose. So, it is known as crude oil.

12. ● Petroleum is a versatile source of energy and important
for the economy of the country. So it is also known as
black gold.
● The chemical compounds that originate from petroleum
are known as petrochemicals.

13. Origin of Petroleum
● Petroleum was formed from the 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.

16. Refining of petroleum
● Petroleum is a dark oily liquid which is a mixture of
various constituents such as petroleum gas, petrol,
diesel, lubricating oil, paraffin wax, etc.
● The process of separating the various
constituents/fractions of petroleum is known as refining.
It is carried out in a petroleum refinery.

17. ● The method involves vapourising the crude oil, in a
tubular furnace for about 400 degree celsius and
passing the vapour into a long fractionating column.
● The higher boiling fractions condenses near the lower
part of the column while the low boiling fractions
condenses at different heights in the fractionating
columns.
● The uncondensed gas, known as petroleum gas,
escapes through an outlet situated at the top of the
column.

18. Fractional Distillation

19. Fractions Uses
1. Petroleum gases (LPG) Fuel for homes and industry
2. Petrol and naphtha Fuel for automobiles, aviation industry, solvent for
dry cleaning chemicals for plastics and insecticides
3. Kerosene Fuel for jet aircraft and homes
4. Diesel oil Fuel for heavy motor vehicles, railway engines,
generators and pumps
5. Fuel oil Fuels for ships and industrial fuel for boilers,
furnaces etc
6. Residue
(i) Lubricating Oil
Lubricants for machines, for making nail polishes
and waxes
(ii) Paraffin wax For making candles, ointments, vaseline, grease,
shoe polishes etc
(iii) Bitumen For surfacing roads, making paints and weather
proofing materials

21. Natural Gas
● Natural gas is a gaseous fossil fuel consisting mainly of
methane. It is found in oil fields along with crude oil or in
a natural gas field.
● It can be easily transported through pipes
● Natural gas is stored under high pressure and is known
as CNG ( compressed natural gas). It is used as
domestic and industrial fuel for transport vehicles and
for power generation.
● It is a less polluting and cleaner fuel.
● A number of chemicals and fertilizers are manufactured
from natural gas.

22. Pollution caused by the combustion of fuels
● Combustion of fuels releases gases such as CO,
CO2,oxides of nitogen, oxides of sulphur etc.
● Solid fuels produces smoke which consists of unburnt
carbon particles and also leave behind ash which
causes air pollution.
● These causes respiratory problems and allergy in
human beings.
● Increased concentration of green house gases leads to
global warming
● Oxides of nitrogen, sulphur etc dissolves in rain water to
form acid rain.

23. To reduce the harmful effects caused by
burning of fossil fuels
a. Use renewable sources of energy like sunlight, wind,
hydro energy and geothermal energy
b. Using conventional sources of energy like coal,
petroleum and natural gas only when absolutely
necessary

24. Tips to save petrol while driving.
● Drive at a constant and moderate speed as
far as possible.
● Switch off the engine at traffic lights or at places where
you have to wait.
● Ensure correct tyre pressure
● Ensure regular maintenance of the vehicle.