Page 63 - Science Class 08

The fuels used in rockets for their propulsion are called propellants. Some of the rocket fuels
are— alcohol, liquid hydrogen, liquid ammonia, kerosene oil, hydrazine and paraffin.

Products of Petroleum

Frac on Boiling Range Uses
1. Gas 16.4° to 30°C It is used as a fuel, in the produc on
of carbon black and hydrogen, in the
produc on of liquefied petroleum
gas (LPG) in manufacture of gasoline

2. Gasoline 30° to 175°C It is used as a motor fuel as a solvent for
dry cleaning for making petrol gas

3. Kerosene 175° to 275°C It is used as household fuel, used as an
illuminate (for ligh ng) for making oil gas

4. Gas oil and 250° to 400°C It is used as furnace fuel for diesel
Diesel oil engines

5. Lubrica ng oil, above 400°C It is used as lubrica ng oil, vaseline is
Vaseline, Paraffin used for making toilet goods and grease,
wax, Asphalt paraffin wax is used for making candles.

earth millions of years ago. It is believed that

about 300 million years ago, the earth had
1. What do you mean by exhaus ble dense forests in low lying wetland areas. Due to
sources of energy? natural processes, like flooding, earthquake,
etc., these forests got burried under the soil.
2. Why should we increase our dependency
on non-exhaus ble sources of energy? With the passage of me soil got deposited
over them and the dead plants got compr-
3. What do you mean by natural fuels?
essed. The temperature also rose as they sank
4. What is petroleum? deeper and deeper. Under high pressure and

5. How can we separate the components of high temperature, dead plants got slowly
petroleum? converted to coal. As coal contains mainly
carbon, the slow process of conversion of dead
6. Write the uses of gasoline.
vegeta on onto coal is called carboniza on.
COAL Coal is obtained from the coal mines.

Coal is also a fossil fuel. But, coal is made from Coal also contains hydrogen and oxygen. A
the remains of dead plants burried under the nominal amount of nitrogen and sulpher is also

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