Q.5 Tick True/False against the following statements.
(a) Fossil fuels can be made in the laboratory. (T/F)
(b) CNG is more polluting fuel than petrol. (T/F)
(c) Coke is the almost pure form of carbon. (T/F)
(d) Coal tar is a mixture of various substances. (T/F)
(e) Kerosene is not a fossil fuel. (T/F)


Answer :

a) Fossil fuels can be made in the laboratory. ( F )

b) CNG is more polluting fuel than petrol. ( F )

c) Coke is the almost pure form of carbon. ( T )

d) Coal tar is a mixture of various substances. ( T )

e) Kerosene is not a fossil fuel. ( F )

EXPLANATION :

1) Fossil fuels are formed from the remains of dead plants and animals under intense pressure and temperature for millions of years under the earth surface and as these conditions cannot be created in a laboratory, hence fossil fuels cannot be made in the laboratory.

2) CNG is more better than petrol and diesel as CNG is a natural gas which emits less nitrogen oxides (NOx) and particulate matter (PM) during combustion. It is also regarded as green fuel.

3) Coke is a grey, hard and porous fuel with a high carbon content and few impurities which is made by heating coal or oil in the absence of air.

4) The major classes of compounds present in coal-tar include: aromatic hydrocarbons, tar acids, tar bases, aromatic amines, sulphur-containing heterocyclic compounds, and oxygen-containing heterocyclic compounds. Hence this proves that coal tar is a mixture of various substances

5) Kerosene is extracted by refining petroleum. As petroleum is considered as a fossil fuel, hence kerosene is also a fossil fuel.

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