Hydrocarbons (Organic Chemistry)

Total Questions: 23

11. When did the Bhopal Gas tragedy happen? [M.P.P.C.S. (Pre) 2013]

Correct Answer: (a) 2-3 Dec. 1984
Solution:The Bhopal Gas Tragedy resulted from an accident that occurred on the night of December 2-3, 1984. The plant released 42 tonnes of methyl isocyanate (MIC) gas, exposing more than 500,000 people to toxic gases.

12. From the decomposition of which of the following printing ink is formed: [Jharkhand P.C.S. (Pre) 2003]

Correct Answer: (b) Methane
Solution:Methane is a colorless, tasteless, and odorless gas found in marshy areas. It is also present in the decomposition of organic matter and gas released by coal. It is used for the manufacture of carbon black, which is used for making black printing ink.

13. Methane gas producing field is — [U.P.P.C.S. (Pre) 2014]

Correct Answer: (b) Paddy field
Solution:Paddy fields are a major source of atmospheric methane and are estimated to contribute between 50 to 100 million tonnes of methane annually. Source of atmospheric methane due to the anaerobic conditions created in the flooded soil, which are conducive to methanogenic bacteria.

14. Which of the following is correctly matched? [U.P. Lower Sub. (Pre) 2002]

       List-I                                          List-II

  1. Biogas                                    Insecticide
  2. Electrocardiography           Heart disorder
  3. D.D.T.                                    Cow-dung
  4. Nicotine                                 Tobacco

 

 

Correct Answer: (d) 2 and 4
Solution:Biogas -  Biogas is a fuel gas produced from anaerobic digestion of organic matter (like cow-dung).

Electrocardiography - Electrocardiography (ECG or EKG) is a medical test that detects heart problems by measuring the electrical activity of the heart.

D.D.T.  DDT (dichlorodiphenyltrichloroethane) is an insecticide. Cow-dung is used for biogas production.

Nicotine - Nicotine is the addictive alkaloid naturally found in tobacco plants.

Therefore, the correctly matched pairs are 2 and 4.

15. Which one of the following chemicals helps in fruit ripening? [U.P. U.D.A./L.D.A. (Pre) 2010]

Correct Answer: (a) Ethephon
Solution:Ethephon or Ethrel is often used in fruit ripening. It produces ethylene when dissolved in water at a particular pH and is a good substitute for calcium carbide.

16. Which of the following chemicals is used for ripening? [U.P.P.C.S. (Mains) 2011]

Correct Answer: (b) Calcium Carbide
Solution:In artificial fruit ripening, calcium carbide is used as a source of acetylene gas, which acts as a ripening agent similar to ethylene. Its chemical formula is

17. Calcium carbide is used for artificial ripening of green fruits because it produces: [R.A.S./R.T.S. (Pre) 2016]

Correct Answer: (c) Acetylene
Solution:In the artificial ripening of fruit, calcium carbide is sometimes used as a source of acetylene gas, which is a ripening agent similar to Ethylene. Its chemical formula is  CaC₂.

18. Fruit ripening is promoted by which of the following? [U.P.R.O./A.R.O. (Pre) 2014]

Correct Answer: (d) Ethylene
Solution:Ethylene gas is an important natural plant hormone, used to force the ripening of fruits.

19. . Which of the following gas mixture is used in welding gas? [Uttarakhand P.C.S. (Pre) 2005]

Correct Answer: (b) Oxygen and Acetylene
Solution:Oxy-acetylene welding is a common process that uses a mixture of Oxygen and Acetylene to produce a high-temperature flame for cutting and welding metals.

20. Gases used in welding are: [63rd B.P.S.C. (Pre) 2017]

Correct Answer: (c) Oxygen and acetylene
Solution:In gas welding, the mixture of oxygen and acetylene are used.