Coal and petroleum Worksheet-7

Coal and petroleum Worksheet-7


  1. Why is petroleum also known as ‘black gold’?


  1. Can we make coal and petroleum in the laboratory from dead organisms?


  1. Give two disadvantages of using fossil fuels.


  1. Why should the fossil fuels be used with care?


  1. What is meant by fractional distillation? What is the principle on which it is based?


  1. Name two places in India where oil wells are found?


  1. When and where in India were oil wells first found?


  1. State one use of each of the following :

(a) Charcoal               (b) Bone Charcoal              (c) Coke.


  1. Name the products obtained when coal is heated in the absence of air.


  1. How is petroleum gas obtained?


  1. How is 'petrol' related to ’petroleum’? Name four most important products obtained from petroleum.


  1. Why do we use coke for making steel and not coal?


  1. Draw diagram to show petroleum and natural gas deposit.


  1. Name some places where natural gas is found in India. How much are reserves of natural gas?



  1. Petroleum is used as fuel in vehicles, industries and many other places. Due to its great commercial importance it is also called ‘black gold’.


  1. No. The formation of coal and petroleum is a very slow process and conditions required cannot be created in laboratory.


  1. Limited availability  

Fossil fuels take millions of years to form. If we run out of the existing stock of these fuels, we will not get more until natural processes have regenerated them.

Air pollution

 Gases like carbon dioxide, carbon monoxide, sulphur dioxide is released on burning of these fuels which cause air pollution.


  1. Fossil fuels are exhaustible, non-renewable natural resource. Their burning also causes air pollution hence they should be used with care.


  1. Fractional distillation is a process that separates the different components in a chemical mixture according to their different boiling points.

A fractional distillation process is done in a cylinder which has different compartments having different temperature points.

When the mixture is kept in the cylinder, the elements which have the same boiling point as in the compartment it is in, it vaporizes and moves out through a pipe.

The mixture goes on vaporizing as the temperature increases and at last all the elements are removed in separated drums where they are condensed and brought back to their normal state.

Image also in chapter Is matter around us pure Grade 9 CBSE


  1. Oil wells in India are found in Gujarat, Mumbai High and in the river basins of Godavari and Krishna.


  1. Oil wells were first found in Digboi in Assam in 18th century. Digboi has two unique features: a 100-year-old extant oilfield and the world's oldest operating oil refinery.


  1. Charcoal is usually obtained by heating wood in the absence of oxygen. It is usually the impure form of carbon as it contains ash. Due to its high surface area charcoal is used as filter, as a catalyst or as an adsorbent.

Bone charcoal (calcium triphosphate) is obtained by charring animal bones. Bones are heated to high temperatures (400-500o C) in the absence of oxygen. It is used to remove fluoride from water and to filter aquarium water. Bone charcoal is also known as bone black, ivory black , animal charcoal.

Coke is obtained by heating coal in the absence of oxygen. It is used in the extraction of iron from its ore and manufacture of steel.


  1. Coke and coal tar is obtained when coal is heated in the absence of air.


  1. Petroleum gas LPG is obtained by fractional distillation of petroleum i.e. Refining of petroleum


  1. Petrol is obtained as a fraction on refining of petroleum. The other products obtained from petroleum are: kerosene, diesel, petrochemicals, LPG.


  1. Coke is used a reducing agent in the manufacture of steel as it is almost the pure form of carbon .The percentage of carbon in coke is 98%.

Coal is used to produce energy and not as reducing agent.




  1. In India, natural gas has been found in Tripura, Rajasthan, Maharashtra and in the Krishna

Godavari delta. India has vast reserves of natural gas.