Fertilizer Technology

A. Loamy soil is the best soil for vigorous plant growth, while the clayey soil is solid and hence
the plant roots penetrate with difficulty
B. Large excess use of nitrogenous fertiliser in land causes the problem of diarrhoea and cyanosis
C. Application of large excess of Potassic fertiliser in soil increases the valuable carotene in
fruits and vegetables
D. Cereal crops grown on alkaline soil absorb higher amount of fluorides thereby spreading
fluorosis

A. Yellow phosphorous which is the most reactive allotropic form of phosphorous is transported
under water
B. Apatite is the principal material present in phosphate rock which is chemically Ca10 (PO4)6 (F,
Cl, OH)
C. Urea is more hygroscopic than ammonium nitrate
D. Nitrogen fixation means the process of bringing atmospheric nitrogen into combination i.e.
into nitrogen compound form

A. Dehydration of ammonium carbamate to produce urea is endothermic
B. Direct use of liquid ammonia as a fertiliser for a tropical country like India is suitable
C. Gypsum (CaSO4. 2H2O) is obtained as a by-product in the wet process for manufacture of
ortho-phosphoric acid
D. Phosphate rock when reacted with dilute H2SO4 produces superphosphate

A. Nitrogen is normally supplied in fertiliser either in Ammoniacal or the nitrate form, from
which the soil takes it up in the form of ammonium ions or nitrate ions and forms amino acids
B. Calcium present in the fertiliser helps in correcting the soil acidity
C. Particle size range of a good granular fertiliser is 10-15 mesh and it contains less moisture as
compared to finely divided powder form of fertiliser
D. Ammonium nitrate fertiliser is obtained as a by-product in an integrated steel plant having byproduct
coke ovens

A. ‘Green acid’ is the other name of phosphoric acid produced by the reaction of phosphate rock
& sulphuric acid
B. Chemically unreactive nature of red phosphorous is due to its polymeric structure
C. Red phosphorous is the most reactive allotropic form of phosphorous
D. Red phosphorous, which is used in the manufacture of safety matches, is converted into white
phosphorous by vaporisation followed by condensation

A. Reaction of NH3 with HNO3 to produce (NH4)2NO3 is endothermic
B. With increase in NH3/CO2 ratio, urea yield decreases for a given temperature, pressure and
total feed rate
C. Biuret (an intermediate during urea manufacture) is toxic to seeds and animals
D. Both B. and C.

A. All the nitrogenous fertilisers are not soluble in water
B. A straight fertiliser contains only one nutrient
C. Calcium cyanamide is used as weed killer in onion fields
D. The phosphorous nutrient makes the plant stem stronger and increases its branches

A. Exothermic
B. Endothermic
C. Non-catalytic
D. Autocatalytic

A. Uses lower grade phosphate rock
B. Requires lower capital investment in the plant
C. Produces lower purity acid
D. Is very costly

A. Has a pungent smell
B. Vaporises at normal temperature
C. Is toxic and highly corrosive
D. Is in short supply