Explore topic-wise MCQs in Current Affairs.

This section includes 2171 Mcqs, each offering curated multiple-choice questions to sharpen your Current Affairs knowledge and support exam preparation. Choose a topic below to get started.

1751.

Oxidation of ammonia is

A. exothermic
B. endothermic
C. non-catalytic
D. autocatalytic
Answer» B. endothermic
1752.

A fertiliser contains 82% N₂. It could be

A. urea
B. liquid NH₃
C. ammonium nitrate
D. none of these
Answer» C. ammonium nitrate
1753.

Prilling of urea should be accomplished (in a sprayer) just above the melting point of urea with minimum of retention time, otherwise it will result in

A. low bulk density product
B. biuret formation
C. non-spherical prills
D. substantially wet non-flowing and sticky product
Answer» C. non-spherical prills
1754.

A phosphatic fertiliser contains 16% P₂O₅. It could be

A. dicalcium phosphate
B. superphosphate
C. triple superphosphate
D. none of these
Answer» C. triple superphosphate
1755.

Fertiliser value of a nitrogeneous fertiliser is expressed in terms of its __________ content.

A. N₂
B. KNO₃
C. NO₂
D. NHO₃
Answer» B. KNO₃
1756.

Raw materials required for the production of CAN (Calcium ammonium nitrate) is NH₃

A. HNO₃ & limestone
B. CO₂ & H₂SO₄
C. HNO₃ & NH₄Cl
D. CO₂ & KNO₃
Answer» B. CO₂ & H₂SO₄
1757.

Conversion of yellow phosphorus to red phosphorous is done in retorts at 250-450°C in the

A. presence of an inert atmosphere.
B. presence of a reducing atmosphere.
C. absence of air.
D. presence of an oxidising atmosphere.
Answer» D. presence of an oxidising atmosphere.
1758.

Reaction of nitric acid and sulphuric acid with phosphate rock produces

A. nitrophosphate
B. diammonium phosphate
C. tricresyl phosphate
D. tributyl phosphate
Answer» B. diammonium phosphate
1759.

Out of the following, N₂ content is minimum in

A. urea
B. ammonium nitrate
C. ammonium sulphate
D. ammonium chloride
Answer» D. ammonium chloride
1760.

Which of the following is the costliest method for commercial production of hydrogen for ammonia synthesis ?

A. H₂ separation from coke oven gas
B. Steam reforming of naphtha
C. Cracking of natural gas
D. Electrolysis of water
Answer» E.
1761.

In the manufacture of orthophosphoric acid by strong H₂SO₄ leaching wet process, keeping the reactor temperature above 100°C, results in the formation of undesriable

A. CaSO₄ .1/2H₂O and CaSO₄ crystals
B. pyrophosphoric acid
C. metaphosphoric acid
D. all (a), (b) and (c).
Answer» B. pyrophosphoric acid
1762.

Tricresyl phosphate is chemically represented as

A. (CH₃C₆H₄)₃PO₄
B. Ca₁₀(PO₄)₃F₆
C. (NH₄)₂HPO₄
D. NH₄H₂PO₄
Answer» B. Ca₁₀(PO₄)₃F₆
1763.

Phosphatic fertilisers

A. are useful during early stage of the plant growth.
B. accelerate fruit formation in later stages of growth.
C. lessen the effect of excessive nitrogen application.
D. none of these
Answer» C. lessen the effect of excessive nitrogen application.
1764.

Optimum reaction temperature in steam reforming of naphtha is __________ °C.

A. 700 - 1000
B. 300 - 450
C. 1500-1700
D. 100-200
Answer» B. 300 - 450
1765.

CaH₄(PO₄)₂ is the chemical formula of

A. superphosphate
B. triple superphosphate
C. calcium phosphate
D. meta phosphoric acid
Answer» C. calcium phosphate
1766.

Heating a mixture of phosphate rock, coke and sand in an electric furnace produces

A. phosphoric acid
B. ammonium phosphate
C. phosphorous
D. superphosphate
Answer» D. superphosphate
1767.

Nitro-phosphate (manufactured at Trom-bay) is a __________ fertiliser.

A. mixed
B. complex
C. highly hygroscopic
D. highly explosive
Answer» C. highly hygroscopic
1768.

Maximum stability of white phosphorous is at

A. very high pressure
B. atmospheric pressure
C. room temperature
D. >600°C
Answer» E.
1769.

Chemical formula of metaphosphoric acid is

A. H₃PO₄
B. H₄P₂O₇
C. HPO₃
D. same as that of pyrophosphoric acid
Answer» D. same as that of pyrophosphoric acid
1770.

Which fertiliser is made (using coke oven gas) in by products plant of an integrated steel plant ?

A. Urea
B. CAN
C. Ammonium sulphate
D. Superphosphate
Answer» D. Superphosphate
1771.

Nitrogen content of urea is about __________ percent.

A. 10
B. 46
C. 80
D. 94
Answer» C. 80
1772.

The main constituent of rock phosphate is

A. mono-calcium phosphate
B. di-calcium phosphate
C. fluorspar
D. none of these
Answer» C. fluorspar
1773.

HPO₃ is the chemical formula of __________ phosphoric acid.

A. pyro
B. ortho
C. meta
D. none of these
Answer» D. none of these
1774.

NPK fertiliser is a __________ fertiliser.

A. complex
B. mixed
C. nitrogenous
D. phosphatic
Answer» C. nitrogenous
1775.

Maximum nitrogen percentage is in

A. ammonium sulphate.
B. calcium ammonium nitrate.
C. urea.
D. liquid ammonia.
Answer» E.
1776.

Which of the following is the costliest source of hydrogen needed for ammonia manufacture under Indian condition ?

A. Electrolysis of water.
B. Cryogenic removal of H₂ from coke oven gas.
C. Steam reforming of naphtha.
D. Natural gas cracking.
Answer» B. Cryogenic removal of H₂ from coke oven gas.
1777.

Phosphatic fertiliser is graded based on its __________ content.

A. P₂O₃
B. PCl₅
C. P₂O₅
D. H₃PO₄
Answer» D. H₃PO₄
1778.

Monte catini process is a widely used process for the manufacture of

A. urea
B. calcium ammonium nitrate
C. triple superposphate
D. none of these
Answer» B. calcium ammonium nitrate
1779.

Reaction of orthophosphoric acid with phosphate rock produces

A. superphosphate
B. triple superphosphate
C. metaphosphoric acid
D. monoammonium phosphate
Answer» C. metaphosphoric acid
1780.

Potassic fertilisers

A. are useful during early stage of the plant growth.
B. stimulate early growth and accelerate seeding.
C. help in development of starches of potatoes and grain.
D. none of these.
Answer» D. none of these.
1781.

Which of the following gasifiers can be attached to coal based fertiliser plants ?

A. Lurgi (high pressure) gasifier.
B. Kopper-Totzek gasifier.
C. Gasifier working at 20 atm.
D. Gasifier working at 40 atm.
Answer» C. Gasifier working at 20 atm.
1782.

Hydrogen is recovered from coke oven gas on commercial scale (as practised in fertiliser plant at Rourkela) by

A. adsorption on palladium.
B. cryogenic operations (low temperature cooling).
C. absorption (using ethanolamine or pyragalloll solution).
D. none of these.
Answer» C. absorption (using ethanolamine or pyragalloll solution).
1783.

The grade of concrete not recommended by I.S. : 456, is

A. M 100
B. M 200
C. M 300
D. M 500
Answer» E.
1784.

Joints in concrete structures, are provided

A. to reduce the tensile stresses likely to be developed due to evaporation of water
B. to minimise the change in the dimensions of the slab
C. to minimise the necessary cracking
D. all the above.
Answer» E.
1785.

Sand generally contains salt if it is obtained from:

A. nala beds
B. river beds
C. sea beds
D. all the above
Answer» D. all the above
1786.

Bulking of sand is

A. mixing of different sizes of sand particles
B. mixing of lime with sand
C. maximum water with sand
D. swelling of sand when wetted.
Answer» E.
1787.

Horizontal construction joints in concrete walls are generally provided at

A. soffit level
B. window sill level
C. floor level
D. all the above.
Answer» E.
1788.

If P, Y and Z are the weights of cement, fine aggregates and coarse aggregates respetively and W/C is the water cement ratio, the minimum quantity of water to be added to first batch, is obtained by the equation

A. 0.1P + 0.3Y + 0.1Z = W/C x P
B. 0.3P + 0.1Y + 0.01Z = W/C x P
C. 0.4P + 0.2Y + 0.01Z = W/C x P
D. 0.5P + 0.3Y + 0.01Z = W/C x P
Answer» C. 0.4P + 0.2Y + 0.01Z = W/C x P
1789.

If the depth of moist sand in a cylinder is 15 cm and the depth of the sand when fully inundated with water is 12 cm, the bulking of the moist sand, is

A. 10%
B. 12%
C. 15%
D. 25%.
Answer» E.
1790.

A flaky aggregate is said to be elongated if its length is

A. equal to the mean size
B. twice the mean size
C. thrice the mean size
D. four times the mean size
Answer» C. thrice the mean size
1791.

For given workability the grading requiring the least amount of water is one that gives

A. greatest surface area for the given cement and aggregates
B. least surface area for the given cement and aggregates
C. least weight for the given cement and aggregates
D. greatest weight for the given cement and aggregates
Answer» B. least surface area for the given cement and aggregates
1792.

To hydrate 500kg of cement full water needed, is

A. 100 kg
B. 110 kg
C. 120 kg
D. 130 kg
Answer» E.
1793.

Inert material of a cement concrete mix, is

A. water
B. cement
C. aggregate
D. none of these.
Answer» D. none of these.
1794.

The ratio of various ingredients (cement, sand, aggregates) in concrete of grade M 200, is

A. 1 : 2 : 4
B. 1 : 3 : 6
C. 1 : 1.5 : 3
D. 1 : 1 : 2
Answer» D. 1 : 1 : 2
1795.

Non-uniform compaction may cause the concrete

A. porous
B. non-homogeneous
C. reduced strength
D. all the above.
Answer» E.
1796.

Pozzolanic properties exist in

A. shales
B. fly ash
C. pumicite
D. all the above.
Answer» E.
1797.

In the method of voids for determination of the quantity of cement paste, it is assumed that

A. Voids in coarse aggregates are filled by fine aggregates
B. Voids in fine aggregates are filled by the cement paste
C. Volume of fine aggregates is equal to total voids in coarse aggregates plus 10% extra
D. All the above.
Answer» E.
1798.

M10 grade of concrete approximates

A. 1 : 3 : 6 mix
B. 1 : 1 : 2 mix
C. 1 : 2 : 4 mix
D. 1 : 1.5 : 3 mix
Answer» B. 1 : 1 : 2 mix
1799.

If the average compressive strength is 4000 kg/cm² and standard deviation is 500, the co-efficient of variation is

A. 10%
B. 12.5%
C. 15%
D. 18.5 %
Answer» C. 15%
1800.

For road pavements, the cement generally used, is

A. ordinary Portland cement
B. rapid hardening cement
C. low heat cement
D. blast furnace slag cement
Answer» C. low heat cement