Coal And petroleum

Exercise:

1). What are the advantages of using CNG and LPG as fuels?

Ans: The advantages of using CNG and LPG as fuels are as follows

i). They are less polluting.

ii). They are cleaner fuels.

iii). they can be used directly for burning.

iv). Their cost is low.

2). Name the petroleum product used for surfacing of roads.

Ans: Bitumen is the petroleum product used for surfacing of roads.

3). Describe how coal is formed from dead vegetation. What is this process called?

Ans: About 300 million years ago the earth had dense forests in low-lying wetland areas. Due to natural processes, like flooding, these forests got buried under the soil. As more soil deposited over them, they were compressed. The temperature also rose as they sank deeper and deeper. Under high pressure and high temperature, dead plants got slowly converted to coal. As coal contains mainly carbon, the slow process of conversion of dead vegetation into coal is called carbonisation. Since it was formed from the remains of vegetation, coal is also called a fossil fuel.

4). Fill in the blanks.

(a) Fossil fuels are coal, petroleum and Natural gas.

(b) Process of separation of different constituents from petroleum is called refining.

(c) Least polluting fuel for vehicle is CNG.

5). Tick True/False against the following statements.

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

Ans: False

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

Ans: False

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

Ans: True

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

Ans: True

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

Ans: False.

6). Explain why fossil fuels are exhaustible natural resources.

Ans: Fossil fuels are present in limited quantity in nature. They also can be exhausted by human activities. Therefore, fossil fuels are exhaustible natural resource.

7). Describe the characteristics and uses of coke.

Ans: Characteristics of coke

i). It is tough.

ii). It is porous.

iii). It is pure form of carbon.

iv). It is black in colour.

Uses of Coke.

i). It is used in the manufacture of steel.

ii). It is used in the extraction of many metals.

8). Explain the process of formation of petroleum.

Ans: Petroleum was formed from 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.

9). The following Table shows the total power shortage in India from 1991–1997. Show the data in the form of a graph. Plot shortage percentage for the years on the Y-axis and the year on the X-axis.

Additional Questions

Fill in the blanks.

i). Coal was used in railway engines to produce steam to run the engine.

ii). When heated in air, coal burns and produces mainly carbon dioxide gas.

iii). Naphthalene balls used to repel moths and other insects.

iv). Coke is the purest form of carbon.

Write whether True or False.

i). Coal is used as a fuel in various industries.

Ans: True

ii). Coal tar is a pure form of carbon.

Ans: False

iii). Petrol and diesel are obtained from a natural resource called petroleum.

Ans: True.

iv). Many useful substances are obtained from petroleum and natural gas.

Ans: True.

v). First oil well in India was drilled at Makum.

Ans: True

Answer in one sentence.

1). What do you mean by fossil fuels?

Ans: The fuels that formed from the dead remains of living organisms are called as fossil fuels.

2). Name the products of coal.

Ans: Coal is processed in industry to produce coak, coal tar and coal gas.

3). Write the examples of exhaustible natural resources.

Ans: Forests, wildlife, minerals, coal, petroleum and natural gas are exhaustible natural resources.

4). Name any two inexhaustible natural resources.

Ans: Sunlight and air.

Name the following.

i). Which gas is produced when coal burns in air.

Ans: Carbon dioxide.

ii). Purest form of carbon.

Ans: Coke

iii). Name the gas formed when coal is burned in the absence of air.

Ans: Coal gas.

iv). First oil well drilled.

Ans: Pennsylvania, USA.

v). First oil well drilled in India.

Ans: Makum in Assam.

vi). Write the constituents of petroleum that are used as fuel.

Ans: Petrol and diesel.

Define

1). Carbonisation

The slow process of conversion of dead vegetation into coal is called carbonisation.

2). Refining

The process of separating the various constituents of petroleum is known as refining.

3). Petrochemicals

The useful substances formed from natural gas and petroleum are called as petrochemicals.

Answer in short.

1). Write the classification of natural resources on their availability?

Ans: On the basis of availability the natural resources are classified as

(i). Inexhaustible natural resources: These resources are present in unlimited quantity in nature and are not likely to be exhausted by human activities. Examples are: sunlight, air.

(ii) Exhaustible Natural Resources: The amount of these resources in nature is limited. They can be exhausted by human activities. Examples of these resources are forests, wildlife, minerals, coal, petroleum, natural gas etc.

2). What do you mean by fossil fuels?

Ans: The dead remains of plants and animals are known as fossils. The fuel obtained from the remains of dead plants and animals are fossil fuels. Coal, petroleum and natural gas are fossil fuels.

3). Write the advantages of using CNG.

Ans: The advantages of using CNG are as follows.

i). It is less polluting.

ii). It is a cleaner fuel.

 

Write a short note on

1). Coke

Ans: It is a tough, porous and black substance. It is an almost pure form of carbon. Coke is used in the manufacture of steel and in the extraction of many metals.

2). Coal Tar

Ans: It is a black, thick liquid with an unpleasant smell. It is a mixture of about 200 substances. Products obtained from coal tar are used as starting materials for manufacturing various substances used in everyday life and in industry, like synthetic dyes, drugs, explosives, perfumes, plastics, paints, photographic materials, roofing materials, etc.

3). Write a note of petroleum refining.

Ans: Petroleum is a dark oily liquid. It has an unpleasant odour. It is a mixture of various constituents such as petroleum gas, petrol, diesel, lubricating oil, paraffin wa etc. The process of separating various constituents or fractions of petroleum is known as refining. It is carried out in a petroleum refinery.

Give reason.

1). Petroleum is called as ‘black gold’.

Ans: Many useful substances are obtained from petroleum. These are used in the manufacture of detergents, fibres, and manmade plastics. Due its commercial use petroleum is also called ‘black gold’.