Read the passage and answer the questions:
Crude petroleum consists of hydrocarbons of liquid and gaseous states varying in chemical composition, color and specific gravity. It is an essential source of energy for all internal combustion engines in automobiles, railways and aircraft. Its numerous by-products are processed in petrochemical industries, such as fertilizer, synthetic rubber, synthetic fiber, medicines, vaseline, lubricants, wax, soap and cosmetics. Crude petroleum occurs in sedimentary rocks of the tertiary period. Oil exploration and production was systematically taken up after the Oil and Natural Gas Commission was set up in 1956. Till then, Digboi in Assam was the only oil producing region but the scenario changed after 1956. In recent years, new oil deposits have been found at the extreme western and eastern parts of the country. In Assam, Digboi, Naharkatiya and Moran are important oil producing areas. The major oilfields of Gujarat are Ankaleshwar, Kalol, Mehsana, Nawagam, Kosamba and Lunej. Mumbai High which lies 160 km off Mumbai was discovered in 1973 and production commenced in 1976. Oil and natural gas have been found in exploratory wells in Krishna-Godavari and Kaveri basin on the east coast. Oil extracted from the wells is crude oil and contains many impurities. It cannot be used directly. It needs to be refined. There are two types of refineries in India: (a) field-based and (b) market-based. Digboi is an example of field based and Barauni is an example of market based refinery.
Crude petroleum contains ______ that generates energy after burning.
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → hydrocarbons
Option (1) igneous rocks — Incorrect. Petroleum is found in sedimentary rocks and is not made of rock.
Option (2) oxygen — Incorrect. Oxygen from the air is needed for burning, but it is not what petroleum contains as its fuel.
Option (3) hydrocarbons — Correct. Crude petroleum consists of hydrocarbons of liquid and gaseous states. When they burn they release energy, which is why petroleum is an essential source of energy for the engines of automobiles, railways and aircraft.
Option (4) ozone — Incorrect. Ozone is a gas of the upper atmosphere, not a part of crude oil.
Note: This passage is taken almost word for word from the NCERT chapter ‘Mineral and Energy Resources’ (India – People and Economy). The ‘new’ passage on crude oil, Digboi and ONGC was the book’s own petroleum paragraph, almost word for word. Read that paragraph once with care, and all five questions feel like meeting old friends.
NCERT (2025-26): “Petroleum … Crude petroleum consists of hydrocarbons of liquid and gaseous states varying in chemical composition, colour and specific gravity. It is an essential source of energy for all internal combustion engines in automobiles, railways and aircraft. Its numerous by-products are processed in petrochemical industries, such as fertiliser, synthetic rubber, synthetic fibre, medicines, vaseline, lubricants, wax, soap and cosmetics.” |