Organic Chemistry F. The Fuel

21. The main component of Gobar Gas is – [U.P.P.S.C. (GIC) 2010, M.P.P.C.S. (Pre) 1999]

(a) Methane
(b) Ethane
(c) Propane
(d) Chlorine

Correct Answer: (a) Methane

Solution:Biogas typically refers to a mixture of different gases produced by the breakdown of organic matter in the absence of oxygen. Biogas is primarily methane and carbon dioxide and may have small amounts of hydrogen sulfide, moisture, and siloxanes. Biogas or gobar gas generally contains about 50%-75% Methane and about 25%-45% carbon dioxide.

22. Which of the following is the procedure for a biogas plant – [U.P. U.D.A./L.D.A. (Pre) 2013]

(a) Fermentation
(b) Reduction
(c) Hydrogenation
(d) Polymerization

Correct Answer: (a) Fermentation

Solution:The biogas formed from cattle dung and other wastes has a lot of energy which can be stored for a biogas plant by the process of fermentation.

23. Who among the following invented 'Gobar Gas' system? [U.P.P.C.S. (Pre) 2015]

(a) C.V. Raman
(b) J.C. Bose
(c) C.B. Desai
(d) H. Khorana

Correct Answer: (c) C.B. Desai

Solution:The first pilot gas plant for producing methane from cattle dung and other cellulosic organic materials was first designed by S.V. Desai and set up at the Indian Agricultural Research Institute (IARI), New Delhi, during 1941-42.

24. The gas which emits from rice field is – [U.P.P.C.S. (Pre) 2006]

(a) Ethane
(b) Methane
(c) Nitrogen
(d) All of the above

Correct Answer: (b) Methane

Solution:Rice paddies, with their waterlogged and anaerobic conditions, provide an ideal environment for methanogenic bacteria to decompose organic matter, leading to the release of significant amounts of methane (CH₄) into the atmosphere. Nitrous oxide, methane, and carbon dioxide gases emit from rice fields. Ethane, Methane, and nitrogen are given in options, hence option methane is the correct answer.

25. The main component of Liquid Petroleum Gas (LPG) are: [U.P.P.C.S. (Mains) 2013]

(a) Methane, Ethane, and Hexane
(b) Ethane, Pentane, and Hexane
(c) Ethane, Propane, and Butane
(d) Methane, Carbon Monoxide, and Hydrogen

Correct Answer: (c) Ethane, Propane, and Butane

Solution:LPG is the abbreviation or short form for Liquefied Petroleum Gas. Like all fossil fuels, it is a non-renewable source of energy. It is extracted from crude oil and natural gas. The main composition of LPG are hydrocarbons containing three or four carbon atoms. The normal components of LPG thus are propane (C₃H₈) and butane (C₄H₁₀). LPG mixtures contain a little more propane in winter and a little more butane during summer but, on average, the makeup is approximately 65% butane and 35% propane. Small concentrations of other hydrocarbons like ethane may also be present. Ethyl mercaptan is normally used as a stenchiant agent for smell.

26. Which one of the following is the main constituent of LPG? [U.P. P.C.S. (Pre) 2021]

(a) Hexane
(b) Pentane
(c) Butane
(d) Methane

Correct Answer: (c) Butane

Solution:LPG is the abbreviation or short form for Liquefied Petroleum Gas. Like all fossil fuels, it is a non-renewable source of energy. It is extracted from crude oil and natural gas. The main composition of LPG are hydrocarbons containing three or four carbon atoms. The normal components of LPG thus are propane (C₃H₈) and butane (C₄H₁₀). LPG mixtures contain a little more propane in winter and a little more butane during summer but, on average, the makeup is approximately 65% butane and 35% propane. Small concentrations of other hydrocarbons like ethane may also be present. Ethyl mercaptan is normally used as a stenchiant agent for smell.

27. What is the main component of L.P.G.? [Chhattisgarh P.C.S. (Pre) 2005]

(a) Methane
(b) Ethane
(c) Propane
(d) Butane

Correct Answer: (d) Butane

Solution:LPG is the abbreviation or short form for Liquefied Petroleum Gas. Like all fossil fuels, it is a non-renewable source of energy. It is extracted from crude oil and natural gas. The main composition of LPG are hydrocarbons containing three or four carbon atoms. The normal components of LPG thus are propane (C₃H₈) and butane (C₄H₁₀). LPG mixtures contain a little more propane in winter and a little more butane during summer but, on average, the makeup is approximately 65% butane and 35% propane. Small concentrations of other hydrocarbons like ethane may also be present. Ethyl mercaptan is normally used as a stenchiant agent for smell.

28. LPG used as domestic fuel mainly contains – [U.P.R.O./A.R.O. (Mains) 2013]

(a) Methane
(b) Acetylene
(c) Ethylene
(d) Butane

Correct Answer: (d) Butane

Solution:LPG is the abbreviation or short form for Liquefied Petroleum Gas. Like all fossil fuels, it is a non-renewable source of energy. It is extracted from crude oil and natural gas. The main composition of LPG are hydrocarbons containing three or four carbon atoms. The normal components of LPG thus are propane (C₃H₈) and butane (C₄H₁₀). LPG mixtures contain a little more propane in winter and a little more butane during summer but, on average, the makeup is approximately 65% butane and 35% propane. Small concentrations of other hydrocarbons like ethane may also be present. Ethyl mercaptan is normally used as a stenchiant agent for smell.

29. LPG used as domestic fuel chiefly contains: [60th to 62nd B.P.S.C. (Pre) 2016, 67th B.P.S.C. (Pre) 2022]

Correct Answer: (e) None of the above/More than one of the above

Solution:LPG is the abbreviation or short form for Liquefied Petroleum Gas. Like all fossil fuels, it is a non-renewable source of energy. It is extracted from crude oil and natural gas. The main composition of LPG are hydrocarbons containing three or four carbon atoms. The normal components of LPG thus are propane (C₃H₈) and butane (C₄H₁₀). LPG mixtures contain a little more propane in winter and a little more butane during summer but, on average, the makeup is approximately 65% butane and 35% propane. Small concentrations of other hydrocarbons like ethane may also be present. Ethyl mercaptan is normally used as a stenchiant agent for smell.

30. Indane gas is a mixture of – [U.P.P.C.S. (Pre) 2011, Uttarakhand P.C.S. (Pre) 2010, R.A.S./R.T.S. (Pre) 1992]

(a) Butane and Hydrogen
(b) Butane and Oxygen
(c) Butane and Propane
(d) Methane and Oxygen

Correct Answer: (c) Butane and Propane

Solution:LPG is the flammable mixture of hydrocarbon gases used as fuel. Indane gas (LPG) is mainly the mixture of propane (C₃H₈) and butane (C₄H₁₀).