ncert solution class 7 science ch soil
Answers
Explanation:
Solution 1
In addition to the rock particles, the soil contains
(iii) Minerals, organic matter, air and water.
Concept insight: Recall the composition of soil.
Solution 2
The water holding capacity is the highest in
(ii) Clayey soil
Concept insight: The particles of clayey soil is very compact so it has highest water holding capacity.
Solution 3
Concept insight: List the properties of soil.
Solution 4
Soil is formed through the process of weathering. Weathering is a process of physical breakdown and chemical decomposition of rocks and minerals near or at the surface of the earth. This physical and chemical decomposition is primarily done by wind, water, and climate. As a result of these processes, large rock pieces are converted into smaller pieces and eventually to soil.
Concept insight: Weathering is a very slow process through which soil is formed from rocks.
Solution 5
Following are the properties of clayey soil:
i. It has very good water holding capacity.
ii. It is rich in organic matter.
For growing crops such as wheat, gram, and paddy, the soil that is good at retaining water and rich in organic matter is suitable. Therefore, clayey soils having these characteristics are useful for such kind of crops.
Concept insight: Particles of clayey soil are very small so it has good water holding capacity and is also rich in humus.
Solution 6
Clayey soil
Sandy soil
(i)
The proportion of fine particles is higher.
(i)
The proportion of large particles is higher.
(ii)
Particles are packed tightly.
(ii)
Particles are loosely packed.
(iii)
It can hold good amount of water.
(iii)
Its ability to retain water is low.
(iv)
Water cannot drain quickly.
(iv)
Water can drain quickly.
(v)
It is heavy in weight.
(v)
It is light in weight.
(vi)
Less air is trapped between the particles.
(vi)
More air is trapped between the particles.
(vii)
It is rich in humus.
(vii)
It is not rich in humus.
Concept insight: Differences between the properties of different types of soil.
Solution 7
Answer:
here are the solutions for chapter 9 class 7 science.................hope it helps....
