Coal and Petroleum Exercises Answer Chapter 5 Science Class 8
Table of Contents
1. What are the advantages of using CNG and LPG as fuels?
CNG and LPG are the constituents of petroleum. Unlike petrol and Diesels CNG and LPG, they are less polluting. Moreover, they can be transported easily through pipes.
2. Name the petroleum product used for surfacing of roads.
Answer: Bitumen (alkatra)
3. Describe how coal is formed from dead vegetation. What is this process called?
Due to natural acts like flooding forests/vegetation get deposited below the soil. With time more and more soil deposit on it. It increases the pressure inside as well as the temperature. In such conditions dead organisms gradually convert into coal.
4.
Answer: a. Coal, petroleum, and natural gas
b. Refining
c. Compressed natural gas (CNG)
5. 
a. F b. F c. T d. T e. F
Explanation: Refining of petroleum oil also yields kerosene along with petrol and diesel.
6. Explain why fossil fuels are exhaustible natural resources.
Fossil fuels take millions of years to form. Its process can not be completed in the laboratory. So, we call fossil fuels as exhaustible natural resources. We have limited reserves of fossil fuels which will deplete in next few years.
7. Describe the characteristics and uses of coke.
Coke is a blacky, porous substance obtained from coal. It is tough and is an almost pure form of carbon. It is used in making steel and in the extraction of metals.
8. Explain the process of the formation of petroleum.
Petroleum is the dead remains of organisms living in the sea. These organisms are buried inside the sea soil after death and get covered by sand and clays. Over millions of years, under high pressure and temperature in the absence of air dead organism gets converted into petroleum.
See also:
Coal and Petroleum Exercises Answer Chapter 5 Science Class 8
Ref: ch5
