{"id":24349,"date":"2021-06-15T16:24:46","date_gmt":"2021-06-15T10:54:46","guid":{"rendered":"https:\/\/mcq-questions.com\/?p=24349"},"modified":"2022-03-02T10:38:20","modified_gmt":"2022-03-02T05:08:20","slug":"ncert-solutions-for-class-7-science-chapter-9","status":"publish","type":"post","link":"https:\/\/mcq-questions.com\/ncert-solutions-for-class-7-science-chapter-9\/","title":{"rendered":"NCERT Solutions for Class 7 Science Chapter 9 Soil"},"content":{"rendered":"

These NCERT Solutions for Class 7 Science<\/a> Chapter 9 Soil Questions and Answers are prepared by our highly skilled subject experts to help students while preparing for their exams.<\/p>\n

Soil NCERT Solutions for Class 7 Science Chapter 9<\/h2>\n

Class 7 Science Chapter 9 Soil Textbook Exercise Questions and Answers<\/h3>\n

Question 1.
\nIn addition to the rock particles, the soil contains
\na. air and water
\nb. water and plants
\nc. minerals, organic matter, air and water
\nd. water, air and plants
\nAnswer:
\nc. minerals, organic matter, air and water<\/p>\n

Question 2.
\nThe water holding capacity is the highest in
\na. sandy soil
\nb. clayey soil
\nc. loamy soil
\nd. mixture of sand and loam
\nAnswer:
\nb. Clayey soil<\/p>\n

Question 3.
\nMatch the items in Column I with those in Column II:<\/p>\n\n\n\n\n\n\n\n\n
\n

Column I<\/p>\n<\/td>\n

\n

Column II<\/p>\n<\/td>\n<\/tr>\n

1. A home for living organisms<\/td>\n(a) Large particles<\/td>\n<\/tr>\n
2. Upper layer of the soil<\/td>\n(b) All kinds of soil<\/td>\n<\/tr>\n
3. Sandy soil<\/td>\n(c) Dark in colour<\/td>\n<\/tr>\n
4. Middle layer of the soil<\/td>\n(d) Small particles and packed tight<\/td>\n<\/tr>\n
5. Clayey soil<\/td>\n(e) Lesser amount of humus<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

Answer:
\n1. (b)
\n2. (c)
\n3. (a)
\n4. (e)
\n5. (d)<\/p>\n

Question 4.
\nExplain how soil is formed.
\nAnswer:
\nSoil 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.<\/p>\n

\"NCERT<\/p>\n

Question 5.
\nHow is clayey soil useful for crops?
\nAnswer:
\nClayey soil can retain much water and consequently contains a lot of moisture even in summer. That\u2019s why it is the most useful for crops like paddy which requires lot of water. Clayey soil is useful for wheat also.<\/p>\n

Question 6.
\nList the differences between clayey soil and sandy soil.
\nAnswer:<\/p>\n\n\n\n\n\n\n\n\n\n\n
Clayey Soil<\/td>\nSandy Soil<\/td>\n<\/tr>\n
1. Particles are of very small size.<\/td>\n1. Particles are of quite large size.<\/td>\n<\/tr>\n
2. Particles are tightly packed together.<\/td>\n2. Particles are loosely packed.<\/td>\n<\/tr>\n
3. Not aerated enough.<\/td>\n3. Well aerated.<\/td>\n<\/tr>\n
4. Can retain water for long time.<\/td>\n4. Cannot retain water.<\/td>\n<\/tr>\n
5. Water does not drain easily.<\/td>\n5. Water drains easily.<\/td>\n<\/tr>\n
6. Fertile.<\/td>\n6. Not fertile.<\/td>\n<\/tr>\n
7. Suitable for many crops.<\/td>\n7. Not suitable for crops.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

Question 7.
\nSketch the cross section of soil and label the various layers.
\nAnswer:
\n\"NCERT<\/p>\n

Question 8.
\nRazia conducted an experiment in the field related to the rate of percolation. She observed that it took 40 min for 200 mL of water to percolate through the soil sample. Calculate the rate of percolation.
\nAnswer:
\nGiven amount of water = 200 mL
\nPercolation time = 40 min
\nTherefore, percolation rate = \\(\\frac{\\text { Amount of water (mL) }}{\\text { Percolation time (min) }}\\)
\n= \\(\\frac{200 \\mathrm{~mL}}{40 \\mathrm{~min}}\\) = 5 mL\/min<\/p>\n

\"NCERT<\/p>\n

Question 9.
\nExplain how soil pollution and soil erosion could be prevented.
\nAnswer:
\nThe persistent build-up of toxic compounds in the soil is defined as soil pollution. To prevent soil pollution, its causes must be controlled.<\/p>\n