Muriate of potash, the commonest potassic fertiliser, is chemically:
- A.Potassium nitrate
- B.Potassium sulphate
- C.Potassium chloride
- D.Potassium carbonate
Correct answer
Explanation
The correct answer is C, potassium chloride. Muriate of potash is potassium chloride, carrying about sixty per cent potash, and it is the cheapest and most widely used source of potassium for crops; the old word muriate simply means a chloride. Option A is wrong because potassium nitrate, or saltpetre, supplies both potassium and nitrogen and is far more expensive, and its main use is in gun powder and in specialised fertigation. Option B is wrong because potassium sulphate, the sulphate of potash, is used where the crop is sensitive to chloride, as with tobacco and some fruits, and it is dearer. Option D is wrong because potassium carbonate is a laboratory and industrial chemical, used in glass and soap manufacture rather than as a fertiliser.
Read the full article: Industrial Chemistry: Glass, Cement, Fertilisers and PYQs
Practice Questions
View allWhich among the following is not a nitrogenous fertilizer?
- A.Ammonium Sulphate
- B.Calcium Cyanamide
- C.Superphosphate of Lime
- D.Urea
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Superphosphate of lime is made by treating rock phosphate with sulphuric acid, and the nutrient it supplies is phosphorus in the form of available phosphate, not nitrogen; it is therefore a phosphatic fertiliser.
Read the full explanation →What is a fertiliser that supplies two or more than two primary nutrients called?
- A.Straight fertiliser
- B.Organic manure
- C.Green manure
- D.Complex fertiliser
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Nitrogen, phosphorus and potassium are the three primary nutrients, and a fertiliser that carries two or more of them in one chemical compound is called a complex or mixed fertiliser; diammonium phosphate, which supplies both nitrogen and phosphate, and the NPK grades sold by number are the familiar examples.
Read the full explanation →What is the percentage of nitrogen present in farm yard manure (FYM) in general?
- A.0.5
- B.0.6
- C.0.8
- D.0.7
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Farmyard manure is the decomposed mixture of cattle dung, urine and bedding litter, and in general it carries only about half a per cent of nitrogen, along with roughly the same order of phosphate and potash.
Read the full explanation →Which substance is added to cement clinker during grinding to retard the setting of cement?
- A.Gypsum
- B.Fly ash
- C.Silica
- D.Alumina
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About two or three per cent of gypsum, which is calcium sulphate dihydrate, is ground with the clinker because it slows down the hydration of tricalcium aluminate, the compound that would otherwise set almost the moment water was added and leave no time to place the concrete.
Read the full explanation →The main raw materials used in the manufacture of Portland cement are:
- A.Limestone and clay
- B.Gypsum and sand
- C.Bauxite and coke
- D.Dolomite and graphite
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Cement needs one calcareous material, limestone, for its lime, and one argillaceous material, clay or shale, for its silica, alumina and iron oxide; the mixture is burnt in a rotary kiln at about 1450 degrees Celsius to give clinker, which is then ground with gypsum.
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