Chemistry Miscellaneous (Part-1)

Total Questions: 42

11. An active chemical to remove mosquitoes is: [41st B.P.S.C. (Pre) 1996]

Correct Answer: (a) Allethrin
Solution:Allethrin is a pyrethroid synthesized insecticide/pesticide and is an active chemical used to remove mosquitoes.

12. Prallethrin is a common: [U.P. P.C.S. (Mains) 2017]

Correct Answer: (c) Mosquito repellent
Solution:Prallethrin is a pyrethroid insecticide, used in liquid vaporizers as a repellent against mosquitoes.

13. Which of the following is used as a mosquito repellent? [U.P.P.C.S. (Mains) 2009]

Correct Answer: (a) Pyrethrum
Solution:Pyrethrum is a natural botanical insecticide with potent insecticidal activity by targeting the nervous system of mosquitoes.

14. Pyrethrin used in mosquito coils is obtained from: [U.P.P.C.S. (Pre) 2005]

Correct Answer: (a) A seed plant
Solution:Pyrethrins are a class of organic compounds derived from Chrysanthemum cinerariifolium, a seed plant.

15. Which one of the following is used in preparing a natural mosquito repellent? [I.A.S. (Pre) 2021]

Correct Answer: (c) Lemongrass
Solution:Lemongrass, also known as citronella grass or fever grass, is a genus of Asian, African, Australian, and tropical island plants in the grass family. It is used for the production of citronella oil, which is used in soaps, as an insect repellent (especially for mosquitoes and houseflies), in insect sprays and candles, and in aromatherapy.

It is known to be an excellent mosquito repellent. Around 95% of mosquitoes from a specific range of species are either killed or completely repelled due to the intense odour of lemongrass oil.

16. Which chemical substance is used for making rat poison? [47th B.P.S.C. (Pre) 2005]

Correct Answer: (c) Potassium Cyanide
Solution:Potassium cyanide (KCN) and zinc phosphide are highly toxic chemicals used as rodenticides—a poison to kill the mouse.

17. Which one of the following is used as rat poison? [U.P.P.C.S. (Mains) 2012]

Correct Answer: (d) Zinc Phosphide
Solution:Zinc phosphide is a common active ingredient in many rodenticides. When ingested by rodents, it reacts with stomach acid to release phosphine gas, which is highly toxic.

18. Rodenticide is the chemical which is used to control: [Uttarakhand P.C.S. (Mains) 2002]

Correct Answer: (c) Mouse
Solution:Rodenticides are pesticides specifically designed to kill rodents, which include mice, rats, and voles.

19. Aluminium Phosphide is used as: [U.P.P.C.S. (Spl) (Mains) 2008]

Correct Answer: (e) Rodenticide & Fumigant
Solution:Aluminium Phosphide is a highly toxic inorganic compound. It is a cheap, easily available pesticide which causes lethal poisoning by liberation of phosphine gas. It is also used as a fumigant for the preservation of cereals and as a rodenticide.

20. Which of the following is an example of a herbicide? [U.P.P.C.S. (Pre) 2019]

Correct Answer: (a) Sodium chlorate
Solution:Herbicides, also commonly known as weedkillers, are substances used to control unwanted plants. Sodium chlorate (NaClO₃) is an oxidizing agent and is used as a herbicide.