Soil Science - Study Mode

[#441] Nepheline is igneous in origin which is rich in
Correct Answer

(B) Na & K

Explanation

Solution: Nepheline is a rock-forming mineral in the feldspathoid group-a silica-undersaturated aluminosilicate that occurs in intrusive and volcanic rocks with low silica and in their associated pegmatites. Nepheline is igneous in origin and is rich in Na & K. It is used in glass and ceramic manufacturing and other industries.

[#442] Slickensides in black soil are found in
Correct Answer

(B) Subsoil

Explanation

Solution: Slickenside is a smoothly polished surface caused by frictional movement between rocks along the two sides of a fault. It is a surface of the cracks produced in soils containing a high proportion of swelling clays. In black soils, slickensides are found in Subsoil , the layer just below the topsoil.

[#443] Granite and basalt are
Correct Answer

(C) Igneous rock

Explanation

Solution: Granite and Basalt are examples of Igneous rocks, which are formed by the solidification and crystallization of magma. Granite is a coarse-grained intrusive igneous rock composed mostly of quartz, alkali feldspar, and plagioclase. It forms from magma with a high content of silica and alkali metal oxides that slowly cools and solidifies underground. Basalt is a fine-grained extrusive igneous rock formed from the rapid cooling of low viscosity lava rich in magnesium and iron exposed at or very near the surface of a rocky planet or moon.

[#444] Most impotant source of sulphur for Indian soils is
Correct Answer

(D) SSP

Explanation

Solution: The most important source of Sulphur for Indian soils is SSP . SSP (single super phosphate) was the first commercial mineral fertilizer, and it is the foundation for the development of the new plant nutrient industry. It is the only Sulphur providing fertilizer in India that contains water-soluble phosphorus easily absorbed by plants. This multi nutrient fertilizer contains phosphorus (14.5%), Sulphur (11%) and calcium (21%).

[#445] Magnesium is a component part of
Correct Answer

(C) Chlorophyll

Explanation

Solution: Magnesium is the central atom of the chlorophyll molecule located in the centre of the porphyrin head, with each molecule containing 6.7% magnesium. Chlorophyll pigment in the leaves absorbs the sunlight that excites the electrons in the molecules, enabling them to be transferred to other molecules. Chlorophyll and magnesium are connected in this step because magnesium helps the molecule absorb light and keeps the electrons in an excited state so that they can be transferred.