Very Short Answers - Coal and Petroleum, Science, Class 8 | Science Class 8 PDF Download

VERY SHORT ANSWER TYPE QUESTIONS
 

Q. 1. Write the names of two natural substances.
 Ans. (i) Air    (ii) Water

Q. 2. Name two man-made substances.
 Ans. (i) Car    (ii) Computer

Q. 3. Name two natural resources.
 Ans. (i) Air    (ii) Water

Q. 4. Write two exhaustible substances.
 Ans. (i) Coal    (ii) Natural gas

Q. 5. Why are air, water and soil called natural resources?
 Ans. Air, water, and soil are considered natural resources because they are naturally available elements that support life and human activities.
 

Q. 6. Name any two inexhaustible natural resources.
 Ans.  (i) Sunlight (ii) Wind energy

Q. 7. Why are Coal, Petroleum and Natural gas called fossil fuels?
 Ans. Coal, Petroleum, and Natural gas are referred to as fossil fuels because they are formed from ancient plant and animal remains that have undergone geological processes over millions of years.

Q. 8. Which gas is produced when coal burns in air?
 Ans. Carbon dioxide(CO₂) is produced when coal burns in air.
 

Q. 9. Name the gas which is formed when coal is heated in the absence of air.
 Ans. Coal gas.

Q . 10. What is the purest form of carbon?
 Ans. Diamond.
 

Q . 11. What is the main use of coke?
 Ans. It is used as a reducing agent in the extraction of metals from their ores.

Q . 12. How many substances are found in coal tar?
 Ans.Coal tar contains approximately 200 substances.
 

Q . 13. Name the substance obtained from the coal tar and used to repel moths and insects.
 Ans. Naphthalene balls. 

Q . 14. Which substance is used for road surfacing these days?
 Ans. These days bitumen is used for road surfacing in place of coal tar.

Q . 15. Where was the first oil well drilled?
 Ans. The first oil well was drilled in Titusville, Pennsylvania, USA, in 1859.
 

Q . 16. Where and when was the first oil well drilled in India?
 Ans. The first oil well in India was drilled in 1867 at Makum in Assam.
 

Q . 17. Name two fractions of petroleum which are used as fuel.
 Ans. (i) Petrol (ii) Diesel

Q . 18. What are Petrochemicals?    
 Ans. Petrochemicals are useful chemical compounds derived from natural gas and petroleum.

Q . 19. Why is petroleum called black gold?    
 Ans. Petroleum is referred to as black gold due to its high economic value and significance, similar to that of precious gold.
 

Q . 20. Name the places where natural gas is found in our country.    
 Ans. Natural gas is found in regions like Tripura, Rajasthan, Maharashtra, and the Krishna Godavari delta in India.

Q . 21. Expand PCRA.
 Ans. Petroleum Conservation Research Association.
 

Q . 22. Can we use all our natural resources forever?
 Ans. No, we cannot use all our natural resources forever, as they are finite and can be depleted over time.
 

Q . 23. Can air, water and soil be exhausted by human activities?
 Ans. No, air, water, and soil cannot be exhausted by human activities as they are continuously replenished by natural processes.

Q . 24. Is water a limitless source?    
 Ans. Yes, water is a limitless source, but by unwise use and cutting of trees, sources of water can be finished.