Frank Cce Everyday Science Solutions for Class 7 Science Chapter 20 Formative Assessment 2 are provided here with simple step-by-step explanations. These solutions for Formative Assessment 2 are extremely popular among Class 7 students for Science Formative Assessment 2 Solutions come handy for quickly completing your homework and preparing for exams. All questions and answers from the Frank Cce Everyday Science Book of Class 7 Science Chapter 20 are provided here for you for free. You will also love the ad-free experience on Meritnation’s Frank Cce Everyday Science Solutions. All Frank Cce Everyday Science Solutions for class Class 7 Science are prepared by experts and are 100% accurate.

Page No 136:

Question A.1:

New substances are formed by
(a) physical change
(b) chemical change
(c) both of these
(d) none of these

Answer:

(b) chemical change
     New substances are formed by chemical change.

Page No 136:

Question A.2:

Tropical animal with sticky pads is
(a) monkey
(b) red-eyed frog
(c) chameleon
(d) apes

Answer:

(b) red-eyed frog
    The red-eyed frog has sticky pads at the ends of its toes.

Page No 136:

Question A.3:

Uneven heating between equator and the poles causes.
(a) earthquake
(b) tide
(c) flood
(d) wind currents

Answer:

(d) wind currents
      Uneven heating between the equator and the poles causes wind currents.

Page No 136:

Question A.4:

Soil profiles consist of three layers which are called
(a) top soil
(b) horizons
(c) subsoil
(d) bedrock

Answer:

(b) horizons
     The three layers of soil (i.e., top soil, subsoil and bedrock) are called horizons.

Page No 136:

Question A.5:

Rotting dead organic matter in soil is
(a) clay
(b) topsoil
(c) subsoil
(d) humus

Answer:

(d) humus
    The dark, soft and porous layer of soil, which is composed of decaying organic matter is known as humus.

Page No 136:

Question B:

Fill in the blanks:
1. A-Horizon of soil is rich in ............................. .
2. The wings in penguins are modified into ............................. .
3. Stainless steel is an alloy of ............................. .
4. ............................. is the amount of water vapour in the atmosphere.
5. The ............................. soil has very good water holding capacity.

Answer:

  1. A-Horizon of soil is rich in humus.
  2. The wings in penguins are modified into flippers.
  3. Stainless steel is an alloy of iron.
  4. Humidity is the amount of water vapour in the atmosphere.
  5. Clayey soil has very good water holding capacity.

Page No 136:

Question C:

Match the words with correct definitions.

Column A Column B
1. Hibernation (a) A whirling wind, circling around a low pressure centre.
2. Convection current (b) Oxidation of metal under the influence of atmospheric condition
3. Percolation (c) Process of remaining inactive during winter.
4. Corrosion (d) Gradual movement of water through pores in the soil.
5. Tornado (e) Movement of hot and cold air.

Answer:

Column A Column B
1. Hibernation (c) Process of remaining inactive during winter
2. Convection current (e) Movement of hot and cold air 
3. Percolation (d) Gradual movement of water through pores in the soil
4. Corrosion (b) Oxidation of metal under the influence of atmospheric condition
5. Tornado (a) A whirling wind, circling around a low pressure

Page No 136:

Question D:

Write True (T) or False (F):
1. Overgrazing of animals can lead to soil erosion. ( )
2. Respiration is a physical change. ( )
3. The climate of a place is affected by its distance from the sea. ( )
4. The centre of a cyclone is a calm and cloudless area. ( )
5. Average weather pattern prevailing over a long period of time is climate.

Answer:

1. (T)

2. (F)
    Respiration is a chemical change.

3. (T)

4. (T)

5. (T)



Page No 137:

Question E:

Give the soil profile by marking different horizons in the picture given below.
Figure

Answer:

  1. A-horizon: the topsoil
  2. B-horizon: the subsoil
  3. C-horizon
  4. D-horizon: bedrock

Page No 137:

Question F.1:

Define atmospheric pressure.

Answer:

Atmospheric pressure refers to the force exerted per unit area of a surface by air that is directly above that surface.

Page No 137:

Question F.2:

Explain the difference between weather and climate.

Answer:

Weather Climate
Weather is defined as the state of the atmosphere, in terms of temperature, moisture, atmospheric pressure, etc., of a given place at a given time. The average weather over a prolonged period of time is known as climate.

Page No 137:

Question F.3:

Why are loamy soils good for paddy cultivation?

Answer:

Loamy soils have a high water retaining capacity, which is good for paddy cultivation, as it requires a lot of water.

Page No 137:

Question F.4:

What is soil erosion? What are the agents that bring about soil erosion?

Answer:

Soil erosion is defined as the removal of the top layer of soil by agents such as wind and water.

Page No 137:

Question F.5:

Why are metal articles electroplated?

Answer:

Metal articles are electroplated to protect them from corrosion.

Page No 137:

Question G.1:

How uneven heating between equator and the poles leads to wind current?

Answer:

The equator receives direct rays from the Sun. As a result, air at the equator gets hotter than the air at the poles. The hot air over the equator rises, creating a low pressure, compared to the poles. Cooler air from the poles then blows towards the equator, leading to wind currents.

Page No 137:

Question G.2:

How does distance from the sea level influence climate?

Answer:

The distance from the sea influences the climate greatly.​ Proximity to sea influences the humidity at a place. Places located closer to the sea have higher humidity, and this impacts rainfall.

Page No 137:

Question G.3:

How does the atmosphere influence the climate of the earth?

Answer:

The atmosphere absorbs sunlight and heats up. The heat level varies, and depends upon the latitude and the altitude. The temperature variations then cause wind currents, which influences ocean currents and the level of rainfall. Thus, the atmosphere brings about changes in the Earth's climate.

Page No 137:

Question G.4:

Why is soil regarded as our most important natural resource?

Answer:

Soil is an important natural resource because:

  1. It is essential for growing food crops. Plants obtain minerals, nutrients and water from soil.
  2. It contains many useful minerals such as saltpetre, rock salt, gypsum, bauxite, haematite, etc.

Page No 137:

Question G.5:

Explain how painting of an iron grill prevent it from rusting.

Answer:

Iron reacts with air and moisture due to which rust forms over its surface. Iron grills are coated with paint in order to avoid the surface from coming into direct contact with water vapour and/or oxygen present in the atmosphere, which prevents rusting.



View NCERT Solutions for all chapters of Class 7