Soil Science - Study Mode
[#486] Softest mineral is
Correct Answer
(C) Talc
Explanation
Solution: The Softest mineral is Talc . This softest mineral position is given at bottom of Moh's scale of Hardness with a relative hardness value of 1. It has a soapy, greasy feel. Talc is formed by the hydrothermal alteration of ultrabasic rocks or low-grade thermal metamorphism of siliceous dolomites.
[#487] Ammonia anhydrous contains
Correct Answer
(A) 82% nitrogen
Explanation
Solution: Anhydrous Ammonia is an efficient and widely used source of nitrogen fertilizer. It contains 82% of Nitrogen in the ammoniacal form that is easily absorbed by the plants. Anhydrous as the word refers to 'without water', that means the form of ammonia that is without water.
[#488] The porosity is measured by
Correct Answer
(C) $${ ext{P}} = 100 - left( {frac{{{ ext{Bulk Density}}}}{{{ ext{Particle Density}}}}}
ight) imes 100$$
Explanation
Solution: Porosity is the measure of empty spaces in the soil. The porosity of the surface soil usually decreases as the size of the particle increases. The porosity of subsoil is lower than the surface soil due to compaction by gravity. It can be measured by the formulae: $${x08f{P = 100 - }}left( {frac{{{x08f{Bulk}},{x08f{Density}}}}{{{x08f{Particle}},{x08f{Density}}}}}
ight){x08f{ imes 100}}$$
[#489] "Law of restitution" was proposed by
Correct Answer
(C) Liebig
Explanation
Solution: The first law of Restitution is given by Liebig , which states 'always restore the nutrients removed by the farming process, so as not to reduce soil fertility. The Law of minimum is also given by Liebig which states that farm yields are proportional to the minimum amount of any single fertilizer element present, relative to the Plant's need.
[#490] India's rank in fertilisers consumption in the world is
Correct Answer
(D) 3
Explanation
Solution: Fertilization Consumption in India went up by 2.95% from 170 kilogram per hectare to 175 kilogram per hectare. India consumes about 25.6 million tonnes of fertilizers and mostly nitrogen followed by Phosphorous and potassium. India ranks third in the consumption of fertilizer in the world. China is the world’s largest consumer of fertilizers.