Which one of the following is not used as fertilizer?
- A.Ammonium nitrate
- B.Ammonium sulphide
- C.Ammonium phosphate
- D.Ammonium sulphate
Correct answer
Explanation
The correct answer is B, Ammonium sulphide. Ammonium sulphide is an unstable, foul-smelling compound that breaks down to release ammonia and toxic hydrogen sulphide, so it is not used as a fertiliser. Its main use is as a reagent in the laboratory, for example in qualitative analysis to precipitate metal sulphides, and in so-called stink bombs. Fertilisers must be stable salts that release plant nutrients steadily in the soil. Option A is wrong because ammonium nitrate is a widely used nitrogen fertiliser, rich in nitrogen in both its ammonium and nitrate parts, though it is handled carefully as it can explode. Option C is wrong because ammonium phosphates, such as diammonium phosphate (DAP), supply both nitrogen and phosphorus and are among the most used fertilisers in India. Option D is wrong because ammonium sulphate gives nitrogen and sulphur and suits alkaline soils and crops such as paddy and tea. Exam tip: nitrate, phosphate, sulphate of ammonium = fertilisers; sulphide = lab reagent.
Practice Questions
View allA recent movie titled The Man Who Knew Infinity is based on the biography of
- A.S. Ramanujan
- B.S. Chandrasekhar
- C.S. N. Bose
- D.C. V. Raman
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- B.an early human species
- C.a cave system found in North-East India
- D.a geological period in the history of Indian subcontinent
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- A.They protect the body from environmental allergens.
- B.They alleviate the body's pain and inflammation.
- C.They act as immunosuppressants in the body.
- D.They protect the body from the diseases caused by pathogens.
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Read the full explanation →The focal length of the objective lens of a telescope is 50 cm. If the magnification of the telescope is 25, then the focal length of the eye-piece is
- A.12.5 cm
- B.5 cm
- C.2 cm
- D.10 cm
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- A.black gram and wheat.
- B.rice and mustard.
- C.vegetables and fruits.
- D.soya bean and milk.
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