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Balbharti Maharashtra State Board Class 6 History Solutions Chapter 7 India during the Maurya Period Notes, Textbook Exercise Important Questions and Answers.

Maharashtra Board Class 6 History Solutions Chapter 7 India during the Maurya Period

Class 6 History Chapter 7 India during the Maurya Period Textbook Questions and Answers

1. Answer in one sentence:

Question 1.
Why did the satraps begin to fight among themselves?
Answer:
After Alexander’s death, a struggle for power began among the satraps that he had appointed.

Question 2.
Who did Ashoka send to Sri Lanka for the spread of Buddhism?
Answer:
Ashoka sent his own son Mahendra and daughter Sanghamitra to Sri Lanka for the spread of Buddhism.

Question 3.
What were the occupations of the people during the Mauryan period?
Answer:
During the Mauryan period, there were many occupations like carving and engraving on ivory, weaving and dyeing cloth and metal work. Black, glazed pottery was produced. Ship building and technology of making articles of iron had also developed.

Question 4.
Which animal engravings are found on the pillars erected by Emperor Ashoka?
Answer:
Excellent carvings of animals like the lion, elephant, bull are found on the pillars erected by Ashoka.

2. Can you explain ?

Question 1.
Satrap
Answer:
When Alexander was forced to return back to Greece, he appointed Greek officers to administer the conquered territories. They were called satraps.

Question 2.
Sudarshan
Answer:
Emperor Chandragupta Maurya built a dam called ‘Sudarshan’ near Junagadh in Gujarat state.

Question 3.
‘Devanampiyo Piyadasi’
Answer:
The name given to Emperor Ashoka which means beloved of the Gods and he who looks on with affection.

Question 4.
Ashtapad
Answer:
The game of chess was called Ashtapad.

3. Recall and describe:

Question 1.
The extent of Chandragupta Maurya’s empire.
Answer:

• Chandragupta Maurya defeated the Nanda dynasty and established his rule in Magadha.
• He won Avanti and Saurashtra and began to extend the boundaries of his empire.
• On defeating Seleucus Nicator he included the north west region of Kabul, Kandahar and Herat in the Mauryan Empire.

Question 2.
The extent of Ashoka’s empire.
Answer:
Ashoka’s empire extended from Afghanistan in the northwest and Nepal in the north to Karnataka and Andhra Pradesh in the south, and from Bengal in the east to Saurashtra in the west.

4. Match the following:

Question 1.

Column (A)	Column (B)
(1) Emperor Alexander	(a) Ambassador of Seleucus Nicator
(2) Megasthenes	(b) Emperor of Greece
(3) Emperor Ashoka	(c) Emperor of Rome
	(d) Emperor of Magadha

Answer:
1 – b
2 – a
3 – d

5. What is your opinion?

Question 1.
Alexander had to turn back.
Answer:

• During the Indian invasion, Alexander’s army had to suffer severe hardships.
• The army was also away from home for a very long time so the soldiers were eager to go back.
• Therefore, they rebelled, against Alexander and he was forced to go back to Greece.

Question 2.
Coins of Greek kings were characteristic.
Answer:

• The Greek kings minted characteristic coins.
•  On one side, the coin had a picture of the king who had minted the coin and on the other side, a picture of a Greek God.
• The name of the king was also written on the coin.
• Alexander’s coins were of the same type.

Question 3.
Emperor Ashoka decided never to wage war again.
Answer:

• Emperor Ashoka decided never to wage war again when he witnessed the bloodshed and devastation caused by Kalinga war.
• Emperor Ashoka had a change of heart and embraced Buddhism.

6. Describe in your own words:

Question 1.
Public welfare works of Emperor Ashoka
Answer:

• Emperor Ashoka laid stress on the creation of facilities for the welfare of the people.
• He made provision for free medicines and medical treatment for people as well as for animals.
• He built many roads.
• He dug wells and built dharmashalas.

Question 2.
Means of entertainment and sport of the Mauryan period.
Answer:

• Different festivals and functions were celebrated in villages and towns.
• Dance and music concerts were a part of entertainment.
• Wrestling bouts and chariot races were popular.
• Board games and chess called Ashtapad was also popular.

Activity:

• Find out about the public welfare activities carried out by the people’s representatives in your area and write in detail about them.
• Read more about the life of Emperor Ashoka and make a presentation based on it in the form of a play.

Class 6 History Chapter 7 India during the Maurya Period Additional Important Questions and Answers

Complete the sentence by choosing the correct option:

Question 1.
Alexander, the Greek emperor, invaded ______ northwestern frontier in 326 BCE.
(a) China
(b) India
(c) Nepal
Answer:
(b) India

Question 2.
Emperor Alexander appointed Greek officers to _______ the conquered territories.
(a) teach
(b) develop
(c) administer
Answer:
(c) administer

Question 3.
Alexander died on his way back to Greece in 323 BCE at ______ .
(a) Babylon
(b) Sri Lanka
(c) Nepal
Answer:
(a) Babylon

Question 4.
Alexander’s campaign led to an _______ in trade between India and the western world.
(a) decrease
(b) standstill
(c) increase
Answer:
(c) increase

Question 5.
The _______ who accompanied Alexander introduced India to the western world through their writings.
(a) historians
(b) physicians
(c) musicians
Answer:
(a) historians

Question 6.
Greek _________ sculpture Indian art.
(a) dominated
(b) influenced
(c) crippled
Answer:
(b) influenced

Question 7.
Indian kings started _________ similar coins like the Greeks.
(a) printing
(b) sculpting
(c) minting
Answer:
(c) minting

Question 8.
Chandragupta Maurya founded the __________ Empire.
(a) Gupta
(b) Nanda
(c) Maurya
Answer:
(c) Maurya

Question 9.
After Alexander’s death, a struggle for power began among the _____ he had appointed.
(a) satraps
(b) ministers
(c) ambassadors
Answer:
(a) satraps

Question 10.
Seleucus Nicator was Alexander’s _______.
(a) satrap
(b) general
(c) ambassador
Answer:
(b) general

Question 11.
________ became the king of Babylon after Alexander’s death.
(a) Megasthenes
(b) Chandragupta
(c) Seleucus Nicator
Answer:
(c) Seleucus Nicator

Question 12.
________ , Seleucus Nicator’s ambassador stayed back at Chandragupta Maurya’s court.
(a) Megasthenes
(b) Alexander
(c) Ashoka
Answer:
(a) Megasthenes

Question 13.
Megasthene’s book _______ is an important source for the study of India during the Mauryan period.
(a) Maruti
(b) Indica
(c) Honda
Answer:
(b) Indica

Question 14.
Chandragupta was succeeded by his son ______.
(a) Ashoka
(b) Bindusara
(c) Shishunag
Answer:
(b) Bindusara

Question 15.
After Bindusara’s death, his son _______ succeeded to the throne in 273 BCE.
(a) Ashoka
(b) Chandragupta
(c) Samudragupta
Answer:
(a) Ashoka

Question 16.
Emperor Ashoka _______ Kalinga.
(a) dominated
(b) destroyed
(c) conquered
Answer:
(c) conquered

Question 17.
Ashoka was deeply moved by the, ________ of the Kalinga war.
(a) bloodshed
(b) strength
(c) bravery
Answer:
(a) bloodshed

Question 18.
Ashoka had embraced ________.
(a) Christianity
(b) Buddhism
(c) Islam
Answer:
(b) Buddhism

Question 19.
Ashoka sent his own son Mahendra and daughter Sanghamitra to ______ for the spread of Buddhism.
(a) Nepal
(b) Sri Lanka
(c) China
Answer:
(b) Sri Lanka

Question 20.
Ashoka also _________ many stupas and viharas.
(a) built
(b) painted
(c) destroyed
Answer:
(a) built

Question 21.
Ashoka made provisions for free medicines and medical treatment for people as well as for the _______.
(a) travellers
(b) citizens
(c) animals
Answer:
(c) animals

Question 22.
Ashoka dug wells and built _______.
(a) stupas
(b) caves
(c) dharmashalas
Answer:
(c) dharmashalas

Question 23.
There was a Council of Ministers which advised the king in matters of _______.
(a) administration
(b) war
(c) weather
Answer:
(a) administration

Question 24.
During the Maurya period, _______ production had great importance.
(a) agricultural
(b) machine
(c) glassware
Answer:
(a) agricultural

Question 25.
Dance and music concerts were part of ______.
(a) night life
(b) entertainment
(c) competition
Answer:
(b) entertainment

Question 26.
Chess was called ______.
(a) Ashtapad
(b) Chakra
(c) Satraps
Answer:
(a) Ashtapad

Question 27.
The pillars erected by Ashoka are excellent ________ of the Indian sculpture.
(a) statues
(b) showpiece
(c) specimens
Answer:
(c) specimens

Question 28.
The chakra or wheel on the Ashoka pillar at Sarnath has a place of _______ on the Indian national flag.
(a) honour
(b) show
(c) visibility
Answer:
(a) honour

Question 29.
After the decline of Emperor Ashoka, the Mauryan empire began to ______.
(a) expand
(b) decline
(c) incline
Answer:
(b) decline

Match the following:

Question 1.

Column (A)	Column (B)
(1) Chandragupta Maurya (2) Seleucus Nicator	(a) Conquered Kalinga (b Pataliputra
(3) Emperor Ashoka	(c) Founded the Mauryan empire
(4) Capital of Maurya empire	(d) Honoured on the Indian national flag
(5) Chakra on Ashoka pillar at Samath	(e) Alexander’s Army General

Answer:
1 – c
2 – e
3 – a
4 – b
5 – d

Answer in one sentence:

Question 1.
Who were satraps?
Answer:
As Alexander was forced to return back to Greece, he appointed Greek officers called satraps to administer the conquered territories.

Question 2.
When and where did Emperor Alexander die?
Answer:
Alexander died on the way back to Greece in 323 BCE at Babylon.

Question 3.
What gave rise to the Gandhara school of art?
Answer:
Greek sculpture influenced Indian art, giving rise to Gandhara school of art.

Question 4.
Who founded the Mauryan Empire?
Answer:
Chandragupta Maurya founded the Mauryan Empire.

Question 5.
Who was Seleucus Nicator?
Answer:
Seleucus Nicator was Alexander’s general.

Question 6.
Who stayed back at Chandragupta’s court?
Answer:
Megasthenes, Seleucus Nicator’s ambassador stayed back at Chandragupta’s court.

Question 7.
Which book did Megasthenes write?
Answer:
Megasthenes wrote the book ‘Indica’ which is an important source for the study of India during the Mauryan period.

Question 8.
Who succeeded Chandragupta?
Answer:
After Chandragupta renounced the throne, he was succeeded by his son Bindusara.

Question 9.
Who succeeded Bindusara?
Answer:
After Bindusara’s death, his son Ashoka succeeded the throne in 237 BCE.

Question 10.
Which religion did Ashoka embrace?
Answer:
Ashoka embraced Buddhism.

Question 11.
Which was the capital of the Mauryan Empire?
Answer:
Pataliputra was the capital of the Maurya empire.

Question 12.
When did the Mauryan Empire decline?
Answer:
The Mauryan Empire declined after the death of Emperor Ashoka.

Question 13.
Which was the largest empire in ancient India?
Answer:
The Mauryan Empire was the largest empire in ancient India.

Question 14.
What is the significance of Ashoka pillar at Sarnath?
Answer:
The chakra or wheel on the Ashoka pillar at Sarnath has a place of honour on the Indian national flag.

Answer in short:
Question 1.
How did Alexander invade India?
Answer:

• Alexander invaded India’s northwestern frontier.
• Crossing the Indus river he reached Takshashila.
• On the way he met forceful opposition from the local kings. He defeated them all and successfully reached Punjab.

Question 2.
How was Alexander’s campaign advantageous to India?
Answer:
Alexander’s campaign led to an increase in the trade between India and the western world. The historians who accompanied Alexander introduced India to the western world through their writings.

Question 3.
Describe the Sarnath pillar.
Answer:

• The chakra or wheel on the Sarnath pillar has a place of honour on the Indian national flag.
• The pillar has lions on all four sides but only three are visible from the front.

Give reasons:

Question 1.
Ashoka had pillar edicts and stone inscription engraved throughout his kingdom.
Answer:

• Ashoka came to believe that truth, non¬violence, compassion and forgiveness were the important values.
• He wanted to spread these teachings among the common people.
• He, therefore, had pillar edicts and stone inscripitions engraved throughout his kingdom.

Describe the following:

Question 1.
Art and literature during the period of Emperor Ashoka.
Answer:
During the period of Emperor Ashoka, the art of rock cut sculpture was promoted. The pillars erected by Ashoka are excellent specimens of Indian sculpture. There are excellent carvings of animals like the lion, elephant, bull on these pillars. The chakra or wheel on the Ashoka pillar at Sarnath has a place of honour on the Indian national flag.

Balbharti Maharashtra State Board Class 8 Science Solutions Chapter 16 Reflection of Light Notes, Textbook Exercise Important Questions and Answers.

Maharashtra State Board Class 8 Science Solutions Chapter 16 Reflection of Light

Class 8 Science Chapter 16 Reflection of Light Textbook Questions and Answers

1. Fill in the blanks:

Question i.
The perpendicular to the mirror at the point of incidence is called …………. .
Answer:
The perpendicular to the mirror at the point of incidence is called the normal.

Question ii.
The reflection of light from a wooden surface is ……….. reflection.
Answer:
The reflection of light from a wooden surface is irregular reflection.

Question iii.
The working of a kaleidoscope is based on the properties of …………… .
Answer:
The working of a kaleidoscope is based on the properties of reflection of light.

2. Draw a figure describing the following: The reflecting surfaces of two mirrors make an angle of 90° with each other. If a ray incident on one mirror has an angle of incidence of 30°, i draw the ray reflected from the second mirror. What will be its angle of reflection?

Question a.
Draw a figure describing the following: The reflecting surfaces of two mirrors make an angle of 90° with each other. If a ray incident on one mirror has an angle of incidence of 30°, draw the ray reflected from the second mirror. What will be its angle of reflection?
Answer:
For the ray C, the angle of reflection = 60°.

3. How will you explain the statement ‘We cannot see the objects in a dark room’?

Question a.
How will you explain the statement ‘We cannot see the objects in a dark room’?
Answer:
In a room that is completely dark, no light falls on objects. Hence, no light enters our eyes. Hence, there is no sensation of vision, i.e., we cannot see the objects.

4. Explain the difference between regular and irregular reflection of light.

Question a.
Explain the difference between regular and irregular reflection of light.
Answer:
For regular reflection of light, the angles of incidence as well as the angles of reflection are the same for all parallel rays of light incident on the plane and smooth surface. Hence, the reflected rays are also parallel to one another.

For irregular reflection of light, the angles of incidence for parallel rays of light incident on the rough surface are not equal, and hence the angles of reflection are also not equal. Here, the reflected rays are not parallel to one another and spread over a large surface.

5. Draw a figure showing the following:
(a) Incident ray, (b) Normal, (c) Angle of incidence, (d) Angle of reflection, (e) Point of incidence, (f) Reflected ray.

Question a.
Draw a figure showing the following:
(a) Incident ray
(b) Normal
(c) Angle of incidence
(d) Angle of reflection
(e) Point of incidence
(f) Reflected ray.
Answer:

6. Study the following incident.

Swara and Yash were looking in a water-filled vessel. They could see their images clearly in the still water. At that instant, Yash threw a stone in the water. Now their images were blurred. Swara could not understand the reason for the blurring of the images.
Explain the reason for blurring of the images to Swara by answering the following questions:

Question i.
Is there a relation between the reflection of light and the blurring of the images?
Answer:
Yes.

Question ii.
Which types of reflection of light can you notice from this?
Answer:
Regular reflection of light when light is incident on the still water and irregular reflection of light when light is incident on the water as ripples are produced on its surface when a stone is thrown in the water.
Still water behaves as a plane and smooth surface while oscillating water behaves as a rough surface.

Question iii.
Are the laws of reflection followed in these types of reflection?
Answer:
Yes.

7. Solve the following examples.

Question a.
If the angle between the plane mirror and the incident ray is 40°, what are the angles of incidence and reflection?
Solution:
The angle between the plane mirror and the incident ray is 40°. Therefore, the angle of incidence (i) = the angle made by the incident ray with the normal to the plane mirror = 90° – 40° = 50°. The angle of reflection, r – i – 50°.

Question b.
If the angle between the mirror and reflected ray is 23°, what is the angle of incidence of the incident ray?
Solution:
The angle between the mirror and the reflected ray is 23°. Therefore, the angle of reflection (r) = the angle made by the reflected ray with the normal to the plane mirror = 90° – 23° = 67°.
∴ The angle of incidence, i = r = 67°.

Project:

Question a.
Apollo astronauts who stepped on the moon have kept some large mirrors there. Collect information about how the distance to the moon is measured using these.

Class 8 Science Chapter 16 Reflection of Light Important Questions and Answers

Rewrite the following statements by selecting the correct option:

Question 1.
If the angle made by the incident ray with the surface of a plane mirror is 30°, the angle of reflection must be …….. .
(a) 30°
(b) 90°
(c) 60°
(d) 15°
Answer:
If the angle made by the incident ray with the surface of a plane mirror is 30°, the angle of reflection must be 60°.

Question 2.
If the angle of incidence is 40°, the angle made by the reflected ray with the surface of the plane mirror must be ……. .
(a) 40°
(b) 50°
(c) 20°
(d) 80°
Answer:
If the angle of incidence is 40°, the angle made by the reflected ray with the surface of the plane mirror must be 50°.

Question 3.
If the angle of incidence is 20°, the angle made by the reflected ray with the normal to the surface must be ……… .
(a) 20°
(b) 70°
(c) 10°
(d) 40°
Answer:
If the angle of incidence is 20°, the angle made by the reflected ray with the normal to the surface must be 20°.

Question 4.
In a kaleidoscope, the mirrors are inclined to each other at ……. .
(a) 60°
(b) 30°
(c) 45°
(d) 90°
Answer:
In a kaleidoscope, the mirrors are inclined to each other at 60°.

Question 5.
In a periscope, the mirrors are ………….. .
(a) parallel to each other
(b) at right angles to each other
(c) inclined at 45° to each other
(d) inclined at 60° to each other
Answer:
In a periscope, the mirrors are parallel to each other.

Find the odd one out and give the reason:

Question 1.
Plane mirror, Plywood, Wood, Rough tile.
Answer:
Plane mirror. In this case, regular reflection of light takes place. In other cases, reflection of light is irregular.

State whether the following statements are True or False. (If a statement is false, correct it and rewrite it.)

Question 1.
The sense of vision is the most important among our five senses.
Answer:
True.

Question 2.
In a periscope, the angle between the incident ray and the normal to the mirror is 30°.
Answer:
False. (In a periscope, the angle between the incident ray and the normal to the mirror is 45°.)

Answer the following questions in one sentence each:

Question 1.
What is an incident ray?
OR
Define incident ray.
Answer:
A ray of light falling on a surface is called an incident ray.

Question 2.
What is the point of incidence?
OR
Define point of incidence.
Answer:
The point at which the incident ray strikes the surface is called the point of incidence.
[Note: It is also the point of reflection.]

Question 3.
What is the normal?
OR
Define normal.
Answer:
The perpendicular to a surface at the point of incidence is called the normal.

Question 4.
What is the reflected ray?
OR
Define reflected ray.
Answer:
The ray of light that leaves the surface at the point of reflection (the same as the point of incidence) is called the reflected ray.

Question 5.
What is the angle of incidence?
OR
Define angle of incidence.
Answer:
The angle between the incident ray and the normal is called the angle of incidence.

Question 6.
What is the angle of reflection?
OR
Define angle of reflection.
Answer:
The angle between the reflected ray and the normal is called the angle of reflection.

Try this:

Switch off the light in your room at night for some time and then turn it on again.

Question 1.
Could you see the objects in the room clearly when the light was switched off?
Ans.
No.

Question 2.
What did you feel when it was turned on again?
Answer:
We could see the objects clearly. From the above activity you can notice that there is some connection between the sense of vision and light. When we switch off the light at night, the objects in the room cannot be seen and they can be seen as before when the light is switched on again. Thus, we can see objects when the light coming from these objects enters our eyes.

Answer the following questions:

Question 1.
What is reflection of light?
Answer:
When light rays fall on an object, their direction changes and they turn back. This is called the reflection of light.

Try this:

Material:
Torch light, mirror, a stand for hanging the mirror, black paper, comb, white paper, drawing board.
Activity :
1. Fit a white paper tightly over a table or drawing board.
2. Leaving out some portion in the middle of the comb, cover the rest with black paper so that light can only pass through the open central portion.
3. Hold the comb perpendicular to the white paper and throw torch light on its central portion.
4. Adjust the comb and torch so as to get light rays on the white paper. Now keep a mirror in the path of this ray of light as shown in the figure.
5. What do you observe?

Answer:
Light rays which fall on the mirror get reflected and travel in a different direction.

Question 2.
State the laws of reflection of light.
Answer:

1. The angle of reflection is equal to the angle of incidence.
2. The incident ray, the reflected ray and the normal lie in the same plane.
3. The incident ray and the reflected ray are on the opposite sides of the normal.

Try this:

Verification of the laws of reflection of light.
Equipment: Mirror, drawing board, pins, white paper, protractor, scale, pencil.
Activity:

1. Fit a white paper on the drawing board tightly as possible.
2. On the paper draw a line PQ indicating the position of the mirror.
3. Draw a perpendicular ON to PQ at point O.
4. Draw a ray AO making an angle of 30° with ON.
5. Fix two pins S and R along AO.
6. Fix the mirror to a stand and place it along PQ perpendicular to the drawing board.
7. Fix pins at T and U along the line joining the bottom of the reflected images of the pins at S and R.
8. Remove the mirror and join the points T and U and extend it up to O.
9. Measure ZTON.
10. Repeat steps 4 to 9 for angle of incidence equal to 45° and 60° and write down the angles in the following table.

What relation do you find between the angle of incidence and the angle of reflection? If you have done the experiment carefully, you will find that the angle of incidence is equal to the angle of reflection in all three cases. This verifies the laws of reflection.

Question a.
What will happen when a light ray is incident perpendicular to the mirror?
Answer:

Here,
r = i = 90°.
Hence the light ray, on reflection, will retrace the path.

Question 3.
Figures (a) and (b) show three parallel rays, shown in grey, incident on smooth and rough surfaces. The reflected rays drawn using laws of reflection are shown in red.
1. Rays reflected from which surface are parallel to one another?
2. What conclusion can you draw from the figure?
Answer:
1. Rays reflected from the smooth surface are parallel to one another.

2.When the reflecting surface is plane and smooth, the angles of incidence (i) as well as of reflection (r) are the same for all parallel rays incident on the surface. If i₁, i₂, i₃, … are the angles of incidence for incident parallel rays, and r₁, r₂, r₃, …, are the corresponding angles of reflection, then, i₁ = i₂ = i₃ = ……. = r₁ = r₂ = r₃ = ….. This is called regular reflection. Here, the reflected rays are parallel to one another. If the reflecting surface is rough and parallel rays are incident on it, then the angles of incidence are not equal and hence the angles of reflection are also not equal. Here, i₁ ≠ i₂ ≠ i₃ … and r₁ ≠ r₂ ≠ r₃ …, but r₁ = i₁, r₂ = i₂, r₃ = i₃ … as laws of reflection are obeyed. This is called irregular reflection. [Fig.(b)]. Here, the reflected rays are not parallel to one another and spread over a large surface.

Question 4.
What is regular reflection of light?
Answer:
The reflection of light from a plane and smooth surface is called regular reflection of light.

Question 5.
What is irregular reflection of light?
Answer:
The reflection of light from a rough surface is called irregular reflection of light.

Always remember:

1. Laws of reflection are followed in both and regular and irregular reflection.
2. The reflection of light in irregular reflection has not been obtained because the laws of reflection are not followed. They are obtained because the surface is rough (irregular).
3. In irregular reflection, the angles of incidence at different points are different. But at any one point, the angles of incidence and reflection are equal, i.e. i₁ = r₁, i₂ = r₂ …..

Can you recall?

Reflection of reflected light :

Question 1.
How do you see if the barber m a saloon has cut the hair on your neck properly or not?
Answer:
In a saloon, there are mirrors in your front and at back. The image of the back of your head is formed in the mirror at the back. The image of this image is formed in the mirror in front of you. Thus you can see how the hair at the backside of your head is cut.

Question 2.
What type of image do we see in a mirror? What happens to the left and right sides?
Answer:
The image in a plane mirror is upright (erect) and of the same size as the object, but the left and right sides are interchanged. Our right hand appears to be the left hand in the image and the left hand appears to be the right hand in the image. (This is called lateral inversion.)

Question 3.
How do we see the image of the moon in water?
Answer:
The moon is not self luminous. The sunlight falling on the surface of the moon is reflected. This reflected light is again reflected by water to give us the image of the moon.

Try this:

Kaleidoscope:

Activity:

1. Take three rectangular mirrors of the same size.
2. Using sticking tape, stick the mirrors together making a triangle with the reflecting surface facing inwards (see Fig.).
3. Take a white paper of triangular shape and fix it with a tape at one end of the mirrors closing that end.
4. Insert 4 – 5 coloured glass pieces in the hollow of the mirrors.
5. Close the other end also with a paper and make a hole in it.
6. Look through the hole towards light. You will see innumerable images of the glass pieces. These are formed due to reflections by the three mirrors.

You can see different designs in the kaleidoscope. The speciality of a kaleidoscope is that the designs do not easily repeat themselves. Every time the design is different. People making wall papers which are used to decorate walls and cloth designers use a kaleidoscope for making new designs.

Periscope:
Activity:

1. Take a cardboard box. Make slits in the top and bottom sides of the box and place two mirrors so that they make an angle of 45° with the sides of the box and are parallel to each other. Fix them with a sticking tape.
2. Make two windows of 1 inch each near the two mirrors. Now see through the bottom window.
3. Make note of what you see.

From the bottom window, one can see what is in front of the top window. This device is called a periscope. This is used in submarines to see objects above the surface of water. It is also used to observe and keep a watch on the objects or persons on the ground from an underground bunker. The kaleidoscope and periscope both use the properties of reflection of light.

[Note: In a periscope, the angle of incidence is 45° and the two plane mirrors are parallel to each other. Hence, the emergent ray is parallel to the incident ray.]

Example questions for practice:

Question 1.
If the angle between the plane mirror and the incident ray is 20°, what is the angle between the reflected ray
and the plane mirror?
Answer:
20°.

Question 2.
See Fig. In terms of O, what are the angles (i) AON (ii) BON (iii) AOB (iv) BOQ?

Answer:
(i) 90° – θ (ii) 90° – θ (iii) 180° – 2θ

Balbharti Maharashtra State Board Class 8 Science Solutions Chapter 12 Introduction to Acid and Base Notes, Textbook Exercise Important Questions and Answers.

Maharashtra State Board Class 8 Science Solutions Chapter 12 Introduction to Acid and Base

Class 8 Science Chapter 12 Introduction to Acid and Base Textbook Questions and Answers

1. Identify the following solutions, whether they are acid or base.

Question a.

Answer:

2. Write chemical names from given formulae.
H₂SO₄, Ca(OH)₂, HCl, NaOH, KOH, NH₄OH

Question a.
Write the chemical names from given formulae: H₂SO₄, Ca(OH)₂, HCl, NaOH, KOH, NH₄OH
Answer:

1. H₂SO₄ – Sulphuric acid
2. Ca(OH)₂ – Calcium hydroxide
3. HCl – Hydrochloric acid
4. NaOH – Sodium hydroxide
5. KOH – Potassium hydroxide
6. NH₄OH – Ammonium hydroxide

3. Sulphuric acid has highest importance in chemical Industry. Why?

Question a.
Sulphuric acid has highest importance in chemical Industry. Why?
Answer:
Answer:
Sulphuric acid has highest importance in the chemical industry because it is used in the manufacturing of fertilizers like ammonium sulphate and superphosphate of lime. It is used in the manufacturing of hydrochloric acid, nitric acid, phosphoric acid, ether, plastics and metal sulphates. It is also used in the manufacturing of dyes, drugs, perfumes, disinfectants and glue.

4. Give answers.

Question a.
Which acid is used for getting chloride salt?
Answer:
Hydrochloric acid is used for getting chloride salt.

Question b.
By squeezzing lemon on a piece of rock the gas liberated turned lime water milky. Which compound is present in the rock?
Answer:
Metal carbonate is present in the rock.

Question c.
The label on the bottle of chemical is spoiled. How will you find whether the chemical is acidic or not?
Answer:
The chemical is tested with blue litmus paper. If it turns red it is an acidic otherwise tested with red litmus paper, if it turns blue, it is an alkaline.

5. Answer the following questions. 

Question a.
Explain the difference between acid and base.
Answer:
Acids:

1. Acids have sour taste.
2. Acids turn blue litmus red.

Bases:

1. Bases have bitter taste.
2. Bases turn red litmus blue.

Question b.
Why indicator does not affect by salt?
Answer:
Mostly indicators are organic compounds which do not react with a salt.

Question c.
Which substances are produced i by neutralization process?
Answer:
Salt and water are produced in the f neutralization process.

Question d.
Which are the industrial uses of acids?
Answer:
Acids which are used in the industry are:

1. Sulphuric acid
2. Hydrochloric acid
3. Nitric acid.;

1. Sulphuric acid: Sulphuric acid is 5 used (a) in the manufacture of chemical? fertilizers like ammonium sulphate, (b) for cleaning gold and silver articles and (c) in car batteries.

2. Hydrochloric acid: Hydrochloric acid is used (a) to clean toilets and (b) to obtain glucose from starch and also for producing gelatine.

3. Nitric acid: Nitric acid is used (a) in the manufacture of perfumes (b) for engraving on copper, brass or silver and (c) in the manufacture of paints and explosives.

6. Select proper word given in bracket and fill in the blanks.

Question a.
Main constituent of acid is ……………. .
Answer:
Main constituent of acid is H⁺ ion.

Question b.
Main constituent of alkali is …………….. .
Answer:
Main constituent of alkali is OH^– ion.

Question c.
Tartaric acid is a …………… acid.
Answer:
Tartaric acid is a weak acid.

7. Match the pairs. 

Question a.

Group A	Group B
1. Tamarind	a. Acetic acid
2. Curd	b. Citric acid
3. Lemon	c. Tartaric acid
4. Vinegar	d. Lactic acid

Answer:

Group A	Group B
1. Tamarind	c. Tartaric acid
2. Curd	d. Lactic acid
3. Lemon	b. Citric acid
4. Vinegar	a. Acetic acid

8. State true or false.

Question a.
Oxides of metals are alkaline in nature.
Answer:
True.

Question b.
Salt is acidic.
Answer:
False. (Salt is neutral)

Question c.
Metal corrodes due to salts.
Answer:
False. (Acids and bases corrode metals)

Question d.
Salts are neutral.
Answer:
True. (Not all salts neutral)

9. Classify the following substances into acidic, basic and neutral group:
HCl, NaCl, MgO, KCl, CaO, H₂SO₄, HNO₃, H₂O and Na₂CO₃.

Question a.
Classify the following substances into acidic, basic and neutral group:
HCl, NaCl, MgO, KCl, CaO, H₂SO₄, HNO₃, H₂O and Na₂CO₃.
Answer:

Group	Substances
Acid	HCl, H2SO4, HNO3
Base	CaO, MgO, Na2CO3
Neutral	H2O, NaCl, KCl.

Project:

Question a.
Write in your own language the uses and importance of neutralization reaction in daily life.

Class 8 Science Chapter 12 Introduction to Acid and Base Important Questions and Answers

Fill in the blanks:

Question 1.
Acid reacts with metal to form …………. gas.
Answer:
Acid reacts with metal to form hydrogen gas.

Question 2.
DNA is an acid present in our body, it decides …………. properties.
Answer:
DNA is an acid present in our body, it decides heredity properties.

Question 3.
The chemical formula of milk of magnesia is ………….
Answer:
The chemical formula of milk of magnesia is Mg (OH)₂.

Question 4.
…………. are used to control hyperacidity.
Answer:
Antacids are used to control hyperacidity.

Question 5.
Alkali has …………. taste.
Answer:
Alkali has bitter taste.

Question 6.
Proteins are made up of ………….
Answer:
Proteins are made up of amino acids.

Question 7.
…………. is used in batteries.
Answer:
Dil. H₂SO₄ is used in batteries.

Rewrite the following statements by selecting the correct options:

Question 1.
The colour of phenolphthalein indicator in alkaline solution is ………….
(a) yellow
(b) green
(c) orange
(d) pink
Answer:
The colour of phenolphthalein indicator in alkaline solution is pink.

Question 2.
…………. is sour to taste.
(a) An acid
(b) An alkali
(c) A salt
(d) Alcohol
Answer:
An acid is sour to taste.

Question 3.
When phenolphthalein is added to NaOH, the colour of the solution will become ……………… .
(a) colourless
(b) red
(c) pink
(d) yellow
Answer:
When phenolphthalein is added to 5 NaOH, the colour of the solution will become pink.

Question 4.
When phenolphthalein is added to HCl, the colour of the solution will be ………….. .
(a) red
(b) pink
(c) green
(d) colourless
Answer:
When phenolphthalein is added to HCl, the colour of the solution will be colourless.

Question 5.
…………. is a natural indicator.
(a) Phenolphthalein
(b) Methyl orange
(c) Litmus
(d) Methyl red
Answer:
Litmus is a natural indicator.

Question 6.
The litmus paper or the litmus solution is obtained from …………. plants.
(a) moss
(b) rose
(c) hibiscus
(d) lichen
Answer:
The litmus paper or the litmus solution is obtained from lichen plants.

Question 7.
…………. is not an alkali.
(a) Sodium hydroxide
(b) Potassium hydroxide
(c) Copper hydroxide
(d) Calcium hydroxide
Answer:
Copper hydroxide is not an alkali.

Question 8.
…………. is a weak acid.
(a) Hydrochloric acid
(b) Nitric acid
(c) Carbonic acid
(d) Sulphuric acid
Answer:
Carbonic acid is a weak acid.

Question 9.
When methyl orange is added to HCl, the colour of the solution will be …………… .
(a) red
(b) pink
(c) yellow
(d) colourless
Answer:
When methyl orange is added to HCl, the colour of the solution will be pink.

Question 10.
When blue litmus paper is added to NaOH, the colour of the litmus paper will be ……………. .
(a) blue
(b) red
(c) pink
(d) yellow
Answer:
When blue litmus paper is added to NaOH, the colour of the litmus paper will be blue.

State whether the following statements are true or false. If a statement is false, correct it and rewrite:

Question 1.
Red cabbage is a natural indicator.
Answer:
True

Question 2.
Fats of our body are formed by fatty acids.
Answer:
True.

Question 3.
Ammonium hydroxide is used in the production of fertilizers.
Answer:
True.

Question 4.
Lime water is a weak acid.
Answer:
False. (Limewater is a weak base)

Question 5.
Orange colour of methyl orange turns yellow in acid.
Answer:
False. (Orange colour of methyl orange turns pink in acid)

Question 6.
Methyl red turns yellow in alkali.
Answer:
True.

Question 7.
Oxalic acid is used in aerated cold drinks.
Answer:
False. (Carbonic acid is used in aerated cold drinks).

Find the odd one out and justify:

Question 1.
Acetic acid, carbonic acid, hydrochloric acid, nitric acid.
Answer:
Acetic acid. (Others are mineral acids.)

Question 2.
Hydrogen chloride, sodium hydroxide, calcium oxide, ammonia.
Answer:
Hydrogen chloride. (Others are bases.)

Question 3.
HCl, CH₃COOH, H₂SO₄, HNO₃
Answer:
CH₃COOH. (Others are strong acids.)

Question 4.
NaOH, Ca(OH)₂, NH₄OH, Ba(OH)₂
Answer:
NaOH (Others are weak bases.)

Question 5.
H₂SO₄, H₂CO₃, HCl, HNO₃
Answer:
H₂CO₃ (Others are strong acids.)

Question 6.
Citric acid, formic acid, lactic acid, nitric acid.
Answer:
Nitric acid. (Others are organic acids.)

Question 7.
Lime, litmus, phenolphthalein, methyl orange.
Answer:
Lime. (Others are indicators.)

Match the following:

Question 1.

Column ‘A’	Column ‘B’
1. Strong acid	a. Magnesium hydroxide
2. Weak alkali	b. Carbonic acid
3. Weak acid	c. NaOH
4. Strong alkali	d. Nitric acid

Answer:

Column ‘A’	Column ‘B’
1. Strong acid	d. Nitric acid
2. Weak alkali	a. Magnesium hydroxide
3. Weak acid	b. Carbonic acid
4. Strong alkali	c. NaOH

Question 2.

Column ‘A’	Column ‘B’
1. Sodium hydroxide	a. Whitewashing
2. Magnesium hydroxide	b. Fertilizers
3. Calcium hydroxide	c. Washing soap
4. Ammonium hydroxide	d. Antacid

Answer:

Column ‘A’	Column ‘B’
1. Sodium hydroxide	c. Washing soap
2. Magnesium hydroxide	d. Antacid
3. Calcium hydroxide	a. Whitewashing
4. Ammonium hydroxide	b. Fertilizers

Define the following:

1. Acid: A substance which gives H⁺ ions in water is called an acid.

2. Alkali: A substance which gives OH^– ions in water is called an alkali.

3. Indicator: Substances which change their colours in presence of acid or base are called indicators.

4. Neutralization: The reaction between an acid and an alkali to form the r salt and water is termed as neutralization.

Answer the following questions in one sentence each:

Question 1.
What are natural acids?
Answer:
Acids present in foodstuffs are called natural acids.

Question 2.
State three vegetables from which natural indicators can be prepared.
Answer:
Natural indicators: Red cabbage, radish, tomato.

Question 3.
State names of any three strong acids.
Answer:

1. Hydrochloric acid
2. Sulphuric acid
3. Nitric acid.

Question 4.
State the names of the acids found in lemon juice, Amla, tamarind water and curd.
Answer:

1. Lemonuice – citric acid
2. Amla – ascorbic acid
3. tamarind water – tartaric acid
4. curd – lactic acid.

Question 5.
State names of any three alkalis.
Answer:

1. sodium hydroxide
2. potassium hydroxide
3. calcium hydroxide.

Question 6.
State the names of three indicators.
Answer:

1. Litmus paper
2. Methyl orange
3. Phenolphthalein.

Question 7.
State the names of three weak alkalis.
Answer:

1. Calcium hydroxide
2. ammonium hydroxide
3. magnesium hydroxide.

Question 8.
From which plant is litmus obtained?
Answer:
Litmus is obtained from plants called lichens.

Question 9.
Name the antacid which is used to control the hyper acidity.
Answer:
Milk of magnesia [Mg(OH)₂] is used to control the hyper acidity.

Question 10.
How will you neutralize the excess of acid present in the soil?
Answer:
Lime stone or lime water is mixed in the soil to neutralize the excess of acid.

Question 11.
When lemonuice falls on a marble kitchen counter, which is the gas that bubbled out?
Answer:
Carbon dioxide.

Answer the following questions:

Question 1.
What are indicators?
Answer:
Substances which change their colours in presence of acid or base are called indicators.

Question 2.
State two acid-base indicators and mention their colour change.
Answer:
Phenolphthalein and methyl orange are two acid-base indicators. Phenolphthalein is colourless in an acidic solution while it turns pink in a basic solution. Methyl orange gives orange colour with an acidic solution and yellow colour with a basic solution.

Question 3.
State the colour change for each of the following solutions with red litmus, blue litmus, phenolphthalein and methyl orange solutions.
Answer:

Question 4.
Name the acid present in (1) Orange (2) Vinegar (3) Tamarind (4) Curd (5) Tomato (6) Lemon.
Answer:

Substance	Acid
Orange	Citric acid
Vinegar	Acetic acid
Tamarind	Tartaric acid
Curd	Lactic acid
Tomato	Oxalic acid
Lemon	Citric acid

Question 5.
Classify the following into acidic substances, basic substances and salts.
(1) Lime water, (2) soda water, (3) soap water, (4) sea water, (5) sweet limeuice, (6) sugar caneuice, (7) buttermilk, (8) a mixture of ash in water, (9) tamarind water.
Answer:
a. Acidic substances: (1) Soda water, (2) sweet limeuice, (3) buttermilk, (4) tamarind water.
b. Basic substances: (1) Lime water, (2) Soap water, (3) a mixture of ash in water.
c. Salts: (1) Sea water, (2) sugar caneuice.

Question 6.
What happens when sour substances like limeuice, tamarind water falls on shahabad stones or kitchen platform? Why?
Answer:
When sour substances like limeuice, tamarind water falls on shahabad stones or kitchen platform, citric acid present in limeuice and tartaric acid in tamarind water reacts with metal carbonates present in shahabad stones or kitchen platform, carbon dioxide gas is evolved resulting in the formation of uneven surface.

Question 7.
Collect soil samples from your surroundings and find out whether it is acidic or alkaline or neutral?
Answer:
Soil samples collected from the surroundings are acidic in nature.

Question 8.
Which substances are used to clean greenish stains on copper vessels and to shine blackish silver utensils?
Answer:
Tamarind pulp is used to clean greenish stains on copper vessels. To shine blackish silver utensils, ammoniacal solution or limeuice or detergent is used.

Question 9.
Why toothpaste is used for brushing teeth?
Answer:

1. Toothpaste contains fluorides and alkali to neutralize the mouth acid.
2. Hence, the tooth paste, which is generally alkaline, is used for cleaning the teeth as it can neutralize the excess acid in i the mouth and prevent tooth decay.

Question 10.
State the properties of acids.
Answer:

1. Acids are sour in taste.
2. Acid molecules contain hydrogen ion (H⁺) as a main constituent.
3. Acid reacts with metal to form hydrogen gas.
4. Acid reacts with carbonates and liberates CO₂ gas.
5. Blue litmus turns red in acid.

Question 11.
State the uses of acids.
Answer:

1. Acids are used in the production s of chemical fertilizers.
2. Acids are used in the production of explosives, oil purification, medicines, dyes and paints.
3. Hydrochloric acid is used for the preparation of different types of chloride salts.
4. Dil. H₂SO₄ acid is used in the batteries (electric cell).
5. Dil. HCl is used for sterilization of water.
6. Acid is used for making of white paper from wood pulp.

Question 12.
The iron knife shines better after cutting the sour fruits like lemon, raw mangoes. Why?
Answer:
Acids present in sour fruits clean and dissolves the salts present on the surface of iron knife as a result iron knife shines better after cutting the sour fruits.

Question 13.
What is meant by neutralization? Give example.
Answer:
When an acid reacts with an alkali to form a salt and water, it is called neutralization.

Give scientific reasons:

Question 1.
When we have stomachache, doctors prescribe medicine containing magnesium hydroxide.
Answer:

1. There is hydrochloric acid in our stomach which helps in the digestion of food.
2. Sometimes in the stomach, there is more hydrochloric acid than we need.
3. This excess acid causes acidity and indigestion resulting in stomachache.
4. When magnesium hydroxide is administered it neutralizes the extra acid in the stomach.
5. Therefore, magnesium hydroxide is the best cure for stomachache.
6. So, when we have stomachache, doctors prescribe medicine containing magnesium hydroxide.

Question 2.
Quicklime or slaked lime is added to the soil.
Answer:

1. When chemical fertilizers are added to the soil, the soil becomes acidic.
2. To reduce its acidity quicklime or slaked lime is added to the soil.

Question 3.
Tarnished and stained copper vessels are brought to a shine by using tamarind pulp.
Answer:
In due course, unus6d copper vessels
are covered with a coating of black copper oxide and other compounds of copper which tarnish the vessel. Tamarind contains tartaric acid. When the vessel is rubbed with tamarind pulp, tartaric acid reacts with copper oxide and removes the layer. Thus, the copper vessel regains its shine.

Question 4.
Copper and brass utensils are tinned.
Answer:
Copper and brass reacts with i organic acids present in food materials and poisonous salts are formed. Tin does not react with organic acids present in food materials. Therefore, copper or brass vessels are tinned.

Distinguish between acid and alkali. OR Distinguish between the following:

Question 1.
Acid and Alkali:
Answer:

Acid	Alkali
1. Acid has sour taste.	1. Alkali has bitter taste.
2. Acid turns blue litmus red.	2. Alkali turns red litmus blue.
3. An acid in an aqueous solution gives H+ ions.	3. An alkali in an aqueous solution gives OH+ ions.
4. Oxides of non – metals form acids.	4. Oxides of metals form bases.

Activity-based questions:

Activity 1:
Apparatus: Hibiscus, rose, turmeric, red cabbage leaves, filter paper, etc.
Activity: Rub red petals of hibiscus flower on the white filter paper. This gives hibiscus indicator paper. Similarly rub, rose petals on the white filter paper. Cut strips of this paper, it is a rose indicator paper. Take turmeric powder, add a little water in it. Dip filter paper or ordinary paper in the turmeric water for some time.

After drying make strips of that paper. Prepare turmeric indicator paper in this way. Put leaves of red cabbage in small quantity of water and heat it. Once solution of cabbage leaves cool down, dip papers in it and dry it. Make strips of dried paper. In this way prepare red cabbage indicator paper. Put some drops of following substances on the indicator papers prepared by the above method and write the effect in the following table:

Substance	Effect on turmeric paper	Acidic/basic
1. Lime juice	Yellow	Acidic
2. Lime water (calcium hydroxide)	Red	Basic
3.

Activity 2:
Take baking powder. Add a little water to it. Add this solution on to limeuice, vinegar, orangeuice, appleuice, etc. and note the findings.
What do you observe on addition of baking soda solution in the fruituice? Whether bubbles formed or effervescence came out of fruituice?
From the above first activity we came to know that yellow turmeric indicator paper’s turns red in certain solutions. Similarly on addition of baking soda solution in the acidic solution bubbles come out or effervescence is produced.
By these simple and easy activity we can identify acidic or alkaline substance:
[Note for Activity 1 and Activity 2: Students should perform the experiments under the guidance of school teachers and record their observations.]

Activity 3:
Under the guidance of teacher take limeuice, ammonium hydroxide (NH₄OH), dil. hydrochloric acid (dil. HCl) and nitric acid (HNOs) in different test-tubes. Add drops of following indicators in them. Also dip litmus papers in the solutions. Observe and record in the following table.

Balbharti Maharashtra State Board Class 6 Geography Solutions Chapter 4 Weather and Climate Notes, Textbook Exercise Important Questions and Answers.

Maharashtra Board Class 6 Geography Solutions Chapter 4 Weather and Climate

Class 6 Geography Chapter 4 Weather and Climate Textbook Questions and Answers

A. Who am I?

Question 1.
I keep on changing.
Answer:
Weather.

Question 2.
I am not the same in all places.
Answer:
Climate.

Question 3.
I am the solid state of water droplets.
Answer:
Snow.

Question 4.
I am present in the atmosphere in the form of vapour.
Answer:
Moisture.

B. Answer the following:

Question 1.
Why is the climate of Mahabaleshwar cool ?
Answer:
The climate of Mahabaleshwar is cool because it is situated at a high elevation. So, as we move upward from sea-level, the temperature of air decreases.

Question 2.
Why is the climate near the sea humid?
Answer:
The climate near the sea is humid because it contains greater amount of vapour mixed in the air.

Question 3.
What is the difference between weather and climate?
Answer:

Weather	Climate
(i) Weather is described on the basis of the conditions prevailing at the given time.	(i) Climate is described on the basis of conditions prevailing over a longer period of time.
(ii) Weather keeps changing frequently and we can experience the change easily.	(ii) Change in the climate takes place over a long ! period of time. These are not percieved easily.

Question 4.
What are the elements of weather?
Answer:
The elements of weather are:

• Temperature
• Air pressure
• Winds
• Moisture and
• Precipitation.

Question 5.
What effects do nearness to the sea and height above mean sea level have on the climate?
Answer:
Nearness to the sea leads to a humid climate whereas height above mean sea level will lead to a cool climate.

C. For the climatic conditions mentioned in the table, name the representative places known to you. (Use an atlas.)

Hot	Death valley
Hot and humid
Cold
Hot and dry
Cold and dry

Answer:

Hot	Death valley
Hot and humid	Amazon
Cold	Greenland
Hot and dry	Sahara desert
Cold and dry	Atacama desert

D. Complete the following table

Weather	Climate
Short-lived condition of the atmosphere
	Does not change quickly
Expressed with respect to a specific place
	Elements of climate: Temperature, pressure, winds, humidity and precipitation

Answer:

Weather	Climate
Short-lived condition of the atmosphere	Long-lived condition of the atmosphere
Keeps changing	Does not change quickly
Expressed with respect to a specific place	Expressed with respect to a specific region
Elements of weather: Temperature, pressure, winds, humidity and precipitation	Elements of climate: Temperature, pressure, winds, humidity and precipitation

Activity:

Understand the climate of your place with the help of your teacher.

Class 6 Geography Chapter 4 Weather and Climate InText Questions and Answers

Can you tell?

A. The weather conditions of a few places in India are as follows on 10th June. Use the table to answer the questions.

S. No.	Place	State	Time	Weather
(1)	Kochi	Kerala	12.30 pm	Cloudy
(2)	Bhopal	M.P.	12.30 pm	Hot and sunny
(3)	Mussoorie	Uttarakhand	12.30 pm	Cold weather mild sun

Question 1.
In which place will the clothes on a clothesline dry quickly? Why?
Answer:
In Bhopal the clothes on the clothesline will dry quickly. Due to the hot sun the water in the wet clothes get converted into vapour quickly.

Question 2.
In which place will they dry slowly? Why?
Answer:
Clothes will take longer time to dry in Mussoorie because of the medium heat and cold air.

Question 3.
Will the atmospheric conditions at these places always remain the same or will they change?
Answer:
The atmospheric conditions of these places will change from time to time.

B. Which of the following statements are applicable to the conditions that you have experienced today or yesterday at the place where you live?

• It was cold in the morning.
• In the afternoon it become hot and humid.
• It rained suddenly in the afternoon.
• Cool breeze was blowing in the morning.
• Clouds gathered in the evening.
• The night sky was full of stars and a pleasant breeze was blowing.

Answer:
Students have to give answer to this question depending on the weather condition of one particular day where they live.

C. Since childhood you have experienced summers, rainy seasons and winters. On the basis of your experience answer the following questions.

Question 1.
In which months do summer, monsoon season and winter occur in a year from January to December? Show it in a chart.
Answer:

Summer	Rainy season	Winter
February to May	June to September	October to January

Question 2.
Which special clothes do we use if it is raining?
Answer:
If it is raining, we wear a raincoat or carry an umbrella.

Question 3.
When do we use woollen clothes?
Answer:
We wear woollen clothes in winter.

Question 4.
In which season do we mainly use thin cotton clothes?
Answer:
We wear cotton clothes in summer.

Use your brain power!

Question 1.
Which occupation will you practice in cold regions?
Answer:
Occupations practiced in cold region are lumbering and agriculture.

Question 2.
Which occupations will you practice in hot region?
Answer:
Occupations practiced in hot regions are animal husbandry and agriculture.

Observe the following map and write the answer to the question given below it.

Question 1.
An Indian Meteorological Department image of the storm that visited in November 2014 was shown. Tell in which sea the storm was located.
Answer:
Bay of Bengal.

Class 6 Geography Chapter 4 Weather and Climate Additional Important Questions and Answers

Fill in the blanks with the right option in the brackets:

Question 1.
Atmospheric conditions prevailing at a place and at a given time is called ______. (wind, weather, climate)
Answer:
weather

Question 2.
The temperature goes on ______ from the equator towards both the poles. (decreasing, increasing, being constant)
Answer:
decreasing

Question 3.
The horizontal movement of air is called ______. (pressure, humidity, wind)
Answer:
wind

Question 4.
_____ is defined by elements such as temperature, wind and humidity. (precipitation, weather, climate)
Answer:
weather

Question 5.
The air that has greater amount of vapour is called _____ air. (dry, hot, humid)
Answer:
humid

Question 6.
The humidity in the atmosphere is called _______. (moisture, oxygen, heat)
Answer:
moisture

Question 7.
The proportion of moisture in the atmosphere depends on ________.(winds, temperature, air pressure)
Answer:
temperature

Question 8.
Vapour in the atmosphere condenses into water droplets or snow and their showering on the earth is called ________.(precipitation, wind, climate)
Answer:
precipitation

Match the pairs correctly:

Question 1.

A	B
(1) Winds	(a) hailstorm
(2) Moisture	(b) solar energy
(3) Precipitation	(c) the difference in air pressure
(4) Temperature	(d) vapor
(5) Weather	(e) hot, cool, dry, sultry
	(f) humidity

Answer:
1 – c
2 – d
3 – a
4 – b
5 – e

Name the following statements:

Question 1.
Elements of weather:
Answer:
Temperature, pressure, winds, humidity and precipitation.

Question 2.
Forms of precipitation:
Answer:
Rainfall, snowfall and hailstorm.

Question 3.
Climate is generally expressed as:
Answer:
‘Cool and dry ‘or ‘hot and humid’ or ‘hot and dry’, etc.

Question 4.
Factors influencing climate:
Answer:
Latitudinal position, height above sea level, nearness to ocean and oceanic currents.

Answer the following questions in one sentence:

Question 1.
What is precipitation?
Answer:
Vapour in the atmosphere condenses into water droplets or snow particles, which shower on the earth. This is called as precipitation.

Question 2.
What is called air pressure?
Answer:
Air has weight and as a result it creates pressure. This is called air pressure.

Question 3.
What is wind?
Answer:
Air moving from high pressure towards low pressure areas in a horizontal direction is called wind.

Question 4.
What is called humid air?
Answer:
The atmosphere contains vapour. The air that has greater amount of vapour is called humid air.

Give geographical reasons for the following statements:

Question 1.
As we move upward from the sea-level, temperature of the air decreases.
Answer:

• The earth’s surface gets heat from the Sun.
• Thus, the surface gets heated.
• The air close to the earth surface starts becoming hot.
• Later, different layers of air at higher elevation receive heat.
• Therefore, as we move upward from sea-level, the temperature of air decreases.

Question 2.
Air pressure decreases with increasing height.
Answer:

• The lowermost layers of air are subjected to the pressure of the upper layers.
• So, the density of the lower layers of air increases.
• There is greater air pressure near the surface of the earth.
• Therefore, air pressure decreases with increasing height.

Answer the following questions:

Question 1.
What is known as precipitation?
Answer:
Vapour in the atmosphere condenses into water droplets or snow particles. Their showering on the earth is called precipitation.

Question 2.
What is called moisture?
Answer:
The humidity in the atmosphere is called moisture. The proportion of moisture in the atmosphere depends on the temperature. Air with higher temperature holds a greater amount of moisture.

Balbharti Maharashtra State Board Class 6 Geography Solutions Chapter 9 Energy Resources Notes, Textbook Exercise Important Questions and Answers.

Maharashtra Board Class 6 Geography Solutions Chapter 9 Energy Resources

Class 6 Geography Chapter 9 Energy Resources Textbook Questions and Answers

A. What resource will have to be used for the following work:

Question 1.
Rohan wants to fly a kite.
Answer:
Wind Energy

Question 2.
People in an Adivasi hamlet have to be protected from the cold.
Answer:
Wood

Question 3.
Cooking on a picnic.
Answer:
Wood

Question 4.
Salma wants to iron her clothes.
Answer:
Electricity

Question 5.
Starting a railway-engine.
Answer:
Thermal Energy

Question 6.
Heating water for a bath.
Answer:
Electricity

Question 7.
After sunset, making light available inside the house.
Answer:
Electricity

B. Answer the following questions:

Question 1.
Which energy resources does man use the most? Why?
Answer:
(i) The energy resource we use the most is oil as it has a wide array of uses. It is used as fuel which includes petrol, diesel, kerosene, jet fuel, LPG gas, etc.

(ii) It is also used in cosmetics, medicines, paints, lubricants, etc.

Question 2.
Why are energy resources needed?
Answer:

• The demand for energy resources is increasing due to growing population, urbanisation and growing needs of man.
• Energy resources are needed to prepare food, generate electricity, to propel vehicles and for other domestic and industrial needs.
• We engage in various activities to fulfill our needs, for which we need energy from natural resources.
• Our life will come to a standstill without resources like petrol, wind, natural gas, sunlight, besides other resources.

Question 3.
Why do we need to use environment friendly energy resources?
Answer:

• There are many energy resources which are environment-friendly, which are renewable and which aid in harnessing natural processes.
• When we use environment-friendly energy sources such as solar energy, wind energy, energy from waste, etc.
• We are contributing towards environment conservation, preservation and protection.
• This will help in reducing the deterioration of environment due to use of non-eco friendly energy resources apart from reducing problems arising from pollution caused due to burning of fossil fuels and biomass energy, climate change, etc.
• Environment-friendly resources will not only lead to sustainable development but also provide energy security which is the need of the hour.

C. Explain the differences using the points in the brackets:
(availability, environment-friendliness,advantages and drawbacks)

Question 1.
Mineral oil and solar energy
Answer:

Points	Mineral oil	Solar energy
Availability	(i) Limited in nature as it does not last perpetually.	(i) Availability depends on the intensity of sunrays and the duration of sunshine.
Environment-friendliness	(i)  It is not environment friendly as its generation leads to pollution. (ii)  Being highly inflammable it may cause damage to the environment.	(i) Being pollution-free this is an environment-friendly source of energy.
Advantages	(i)  Cheap source of energy. (ii)  Aids in thermal and atomic power generation.	(i)  A solution to global warming. (ii)  Cost effective, provides energy security.
Drawbacks	(i)  Pollutes the environment. (ii)  Highly inflammable.	(i)  Solar panels stop producing electricity after sunset. (ii)  Expensive to store this energy.

Question 2.
Hydel power and power from geothermal source
Answer:

Points	Hydel power	Power from geothermal sources
Availability	(i) Obtained from the kinetic energy of running water which is easily available.	(i) Underground heat is utilized to generate power and it is inexhaustible.
Environment-friendliness	(i) Does not cause any degradation of the environment.	(i) It is an exhaustible energy resource that causes minimum pollution.
Advantages	(i) Reuse of water is possible. Easy availability of water in most places. Energy generation is pollution-free.	(i) If used on a large scale and more efficiently it may reduce global warming.
Disadvantages	(i) When water is not available it can’t produce electricity. (ii) Humans, flora, and fauna may lose natural habitat when hydel power plants are set up.	(i) Only a few sites have the potential to establish geothermal power plants. (ii) High installation cost is involved. (iii) The energy generation capacity is too small.

Activity:

Show the power generation centres on an outline map of India. Write about one of them. Supplement the information with pictures.

Class 6 Geography Chapter 9 Energy Resources InText Questions and Answers

Can you tell?

Observe the pictures and answer the questions:


Question 1.
Which energy resource is used in figure 1 to obtain light?
Answer:
Kerosene.

Question 2.
Where does this resource come from?
Answer:
It is found under the land surface and also below the ocean floor.

Question 3.
Figure 2 shows fuel being filled in a motor car. From where was the energy resource brought to the pump?
Answer:
Fuel comes to the pump from petroleum refinery, an industrial process plant where crude oil is being processed and refined.

Question 4.
Figure 3 shows Malati with her pinwheel and her father winnowing grain. Who is helping both of them?
Answer:
Wind energy.

Question 5.
Which energy resource is used for lighting a lamp, running a rickshaw and heating oil as shown in figure 5?
Answer:
LPG is used for lighting a lamp and heating oil and CNG is used for running a rickshaw.

Question 6.
What are the various purposes for which man use sunlight?
Answer:
For growing foodgrains, drying clothes, heating water and cooking food, to generate electricity and for multiple other uses we use sunlight.

Question 7.
For which of the above energy resources do we have to spend money?
Answer:
We have to spend money for mineral oil and natural gas.

Observe the map and answer the questions given below:

Question 1.
Name the states which have coal fields
Answer:
Odisha, Chhattisgarh, Jharkhand, Madhya Pradesh, Maharashtra, West Bengal and Gujarat.

Question 2.
Name the mineral oil field in the Arabian Sea.
Answer:
Mumbai High.

Question 3.
Name two states which have coal fields on a large scale.
Answer:

• Chhattisgarh
• Jharkhand

Question 4.
Which mineral oil fields are located in North¬east India?
Answer:
Makum, Digboi, Naharkatiya, Nunmati, Lakhani.

Question 5.
The reserves of which mineral are found in the Godavari Basin?
Answer:
Coal reserves are found in the Godavari Basin.

Question 6.
Which of the states have mineral reserves in the Godavari basin?
Answer:
Telangana, Chhattisgarh, Maharashtra and Madhya Pradesh.

Question 7.
Name four hydel power stations in our state.
Answer:
Koyna Hydroelectric project, Jayakwadi Hydroelectric project, Sardar Sarovar Hydroelectric project, Warna Hydroelectric project.

Question 8.
What kind of energy is produced with the help of the devices shown in the photograph?
(Pg. 59 Text Book)

Answer:
Solar Energy is generated.

Class 6 Geography Chapter 9 Energy Resources Additional Important Questions and Answers

Fill in the blanks choosing the correct options:

Question 1.
In ______ it is necessary to bumthe energy resources directly to generate electricity, (geo-thermal power stations, thermal power stations, hydel power stations)
Answer:
thermal power stations

Question 2.
In villages, ______ is used on a large scale for cooking on earthen stoves. (wood, kerosene, liquid petroleum gas)
Answer:
wood

Question 3.
Low quality coal is used for _________ .(industries, thermal power station, cooking)
Answer:
cooking

Question 4.
High quality coal is used in ________.(geo-thermal power stations, thermal power stations, hydel power stations)
geo-thermal power stations

Question 5.
Mineral oil is obtained from under land surface and also ________.(below the ocean floor, on the land surface, decomposed plants and animals)
Answer:
below the ocean floor

Question 6.
Mineral oil reserves are ________ in nature. (limited, unlimited, low)
Answer:
limited

Question 7.
________ oil is in great demand. (Coal, Mineral, Gas)
Answer:
Mineral

Question 8.
Mineral oil is also called _________.(magic oil, priceless treasure, black gold)
Answer:
black gold

Question 9.
__________ originate from the remains of dead plants and animals. (Bio-fuels, Hydel power, Kinetic energy)
Answer:
Bio-fuels

Question 10.
________is used in sailboats. (Solar energy, Wind energy, Geo-thermal energy)
Answer:
Wind energy

Question 11.
For power generation a wind speed of 40 to _______ is required. (90 kmph, 100 kmph, 50 kmph)
Answer:
50 kmph

Question 12.
Intensity of solar energy is the maximum in the ______ zone. (torrid, temperate, frigid)
Answer:
torrid

Question 13.
______ can be used on a large scale in a peninsular country like India. (Tidal energy, Geo-thermal, Wind energy)
Answer:
Tidal energy

Question 14.
Underground heat is utilised to generate _________.(hydel power, tidal energy, geo-thermal energy)
Answer:
geo-thermal energy

Match the pairs correctly:

Question 1.

Column A	Column B
(1) Hydel power	(a) power generated with the help of the speed and force of waves
(2) Atomic energy	(b) power obtained from the kinetic energy of running water
(3) Tidal energy	(c) underground heat is utilised to generate power
(4) Geo-thermal energy	(d) splitting of the atoms of minerals like uranium and thorium
(5) Wind energy	(e) solar energy
	(f) kinetic energy

Answer:
1 – b
2 – d
3 – a
4 – c
5 – f

State whether the following statements are true or false, correct the wrong statement:

Question 1.
All substance-based energy resources are conventional.
Answer:
False. Except for atomic energy, all other resources are conventional.

Question 2.
In the long run, process-based energy resources are environment-friendly.
Answer:
True

Question 3.
Kinetic energy can be used to generate power or electricity.
Answer:
True

Question 4.
Low quality coal is used in industries.
Answer:
False. Low quality Ooal is used in cooking while high-quality coal is used in industries.

Question 5.
Hydel power is not an environmental-friendly energy resource.
Answer:
False. Hydel power obtained from the kinetic energy of running water does not cause any degradation of the environment so it is environment-friendly.

Question 6.
Solar energy is maximum in the torrid zone.
Answer:
True

Question 7.
Tidal energy is pollution free and everlasting.
Answer:
True

Name the following:

Question 1.
Two examples of substance-based energy resources:
Answer:

• Coal
• Mineral oil

Question 2.
Two examples of process based energy resources.
Answer:

• Sun
• Wind

Question 3.
Energy resources which originate from the remains of dead plants and animals:
Answer:
Bio-fuels

Question 4.
Two countries which use atomic energy:
Answer:

• India
• USA

Question 5.
Two hydel power stations of India:
Answer:

• Bhakra-Nangal in the Punjab
• Koyna in Maharashtra

Question 6.
States in India where windmills have been erected:
Answer:

• Maharashtra
• Karnataka

Question 7.
Devices which can be run on solar power:
Answer:

• Lamps
• Heaters

Question 8.
Two places where hot water springs are seen:
Answer:

• Vajreshwari in Maharashtra
• Manikaran in Himachal Pradesh

Answer the following questions in one sentence each:

Question 1.
How are energy resources classified?
Answer:
Energy resources can be classified in many ways such as conventional – non-conventional, biotic – abiotic, renewable – non-renewable, substance-based – process-based, etc.

Question 2.
Write any one difference between: Substance-based energy resources and process based energy resources.
Answer:
Generation of substance-based energy resources leads to pollution while that of process based energy resource is pollution free.

Question 3.
Write any one use of kinetic energy.
Answer:
Kinetic energy can be used to generate power or electricity.

Question 4.
How was coal formed?
Answer:
Long ago, plant and animal remains got buried due to earth movements and they were then decomposed due to pressure and heat, leaving behind the element carbon and this is how coal was formed.

Question 5.
Apart from mineral oil what else is found in mineral oil wells?
Answer:
In most of the mineral oil wells, apart from minerals, natural gas is also found.

Question 6.
Which are the biotic waste materials from which biogas is generated?
Answer:
Biogas is generated from biotic waste material such as faeces of animals, dead leaves, shells, etc.

Question 7.
Why have some farmers raised biogas plants in their own yards?
Answer:
Some farmers have raised biogas plants in their own yards to cater to their domestic needs.

Question 8.
Which is the major problem faced by major metropolitan cities?
Answer:
Waste disposal is the major problem faced by major metropolitan cities.

Question 9.
How is wind energy used to generate electricity?
Answer:
Due to speed of the wind, the windmills turn, generating kinetic energy which in turn is further converted into electricity.

Question 10.
What does generation of solar power depend on?
Answer:
The generation of solar power depends on the intensity of sunrays and the duration of sunshine.

Question 11.
Which are the movements of ocean water that go on continuously?
Answer:
Sea waves and tides are the movements of ocean water that go on continuously

Give geographical reasons for the following statements:

Question 1.
Several changes took place in the use of energy resources and devices.
Answer:

• We engage in various activities to fulfill our needs, for which we need energy.
• In the past, human labour and animals were used for many tasks.
• Gradually man’s needs increased and with it, several changes took place in the use of energy resource and devices.

Question 2.
The cost of mineral oil is very high.
Answer:

• Mineral oil reserves are limited in nature.
• However, this oil is in great demand. Hence its cost is very high.

Question 3.
Mineral oil is called ‘black gold’.
Answer:
Mineral oil is called ‘black gold’ because it has a blackish colour and it is costly.

Question 4.
In India, there is a lot of scope for using solar energy.
Answer:

• We get light and heat from the sun.
• We have seen that intensity of solar energy is the maximum in the torrid zone.
• India which is in the torrid zone, therefore, has a lot of scope for using solar energy.

Question 5.
Process-based energy resources are environment-friendly.
Answer:
The process-based energy resources cause minimum pollution. So, process-based energy resources are environment-friendly.

Answer in 2-3 sentences:

Question 1.
Energy from waste material can help solve the problem of waste disposal in cities. Explain.
Answer:

• Waste is generated daily on a very large scale in a big metropolitan cities.
• Waste disposal is a major problem in such places.
• This waste can be segregated to use the biotic component to generate gas which can be used to generate power.
• In the future, this may help to solve the problem of waste disposal in cities

Question 2.
Explain the term atomic energy.
Answer:

• Splitting of the atoms of minerals like uranium and thorium can be used for power generation.
• In this process, using very small quantities of minerals, energy can be generated on a very large scale.

Question 3.
How must we use energy resources?
Answer:

• Energy resources must be used very carefully.
• The demand for energy is increasing all the time due to growing population, urbanisation and growing needs of man. ,
• It is necessary to use alternative and non- conventional energy resources to meet these needs.
• It is also necessary to use energy frugally.

Balbharti Maharashtra State Board Class 6 Geography Solutions Chapter 8 Natural Resources Notes, Textbook Exercise Important Questions and Answers.

Maharashtra Board Class 6 Geography Solutions Chapter 8 Natural Resources

Class 6 Geography Chapter 8 Natural Resources Textbook Questions and Answers

A. What is the use of the following resources?

Question 1.
Water
Answer:

• Right from the time we get up in the morning, we keep on using water till we go to bed at night.
• We obtain salt from sea water.
• Plants and aquatic animals like fish also live in water.

Question 2.
Forests
Answer:

• We collect wood from the forest for various purposes.
• In order to fulfill our needs we also obtain products like rubber, resin, fruits, medicinal plants, etc. from forests.
• Forests are the habitat of many animals.

Question 3.
Animals
Answer:

• Man uses animals for a variety of reasons.
• Horses, oxen, camel, asses, etc. are animals employed for ploughing, riding, transporting goods, etc.
• Goats, cows, buffaloes are used as milch animals.
• Animals provide meat, eggs, bone powder, hide, etc.

Question 4.
Minerals
Answer:

• We get different metals and chemicals from minerals.
• Some chemicals are used in preparing different medicines.
• Metallic minerals are used for obtaining different metals such as iron, bauxite, etc.
• Non-metallic minerals are used in obtaining various chemicals like gypsum, rock salt, calcite, etc.

Question 5.
Land.
Answer:

• Living things that are bom on land, grow, live and die on the land itself.
• Land is used for construction as well as trade.

B. Complete the following flow chart:

Answer:

C. Answer the following questions:

Question 1.
What factors influence the formation of soil?
Answer:
The formation of soil mainly depends on the original rock, climate, organic components, slope of the land and time.

Question 2.
Which products are obtained from forests?
Answer:
We obtain products like wood, rubber, resin, fruits, medicinal plants, etc. from forests.

Question 3.
What are the uses of minerals?
Answer:
Metallic minerals are used for obtaining different metals such as iron, bauxite, etc. and non-metallic minerals are used in obtaining various chemicals like gypsum, rock salt, calcite, etc.

Question 4.
What are the purposes for which land is used?
Answer:

• Living things that are bom on land, grow, live and die on land itself.
• Construction and trade are some other purposes for which land is used.

Question 5.
Why are various living things found on the land in different proportions?
Answer:
Depending on the characteristics of land and climate, various living things are found on land in different proportions.

Activity:

Collect the pictures of and information about the sources of freshwater.

Class 6 Geography Chapter 8 Natural Resources Textbook Questions and Answers

Can you tell?

Observe the picture given in figure 8.1. and answer the following question.

Question 1.
What do you see in the pictures?
Answer:
I can see different animals and plants in the given pictuers.

Question 2.
How many of these animals or plants do you know?
Answer:
I know all these animals and plants in the given picture.

Question 3.
Which of these things have you seen in reality?
Answer:
I have seen all the cotton ball, mango and horse in reality.

Question 4.
Have you ever used these things or seen them being used?
Answer:
Yes, I have.

Question 5.
Which of our needs do some of these fulfill?
Answer:

• Horse is used in transportation
•  Mango is a fruit we eat from
• Cotton is used to make cloth.

Question 6.
What probable use of the unused things can you think of?
Answer:

• Octopus can be kept in aquarium
• Lizards can be kept in the gardens to eat tiny insects.

Observe all the figures and discuss them in the class:



Can you tell?

Question 1.
What different activities are the individuals in the pictures engaged in?
Answer:
The different activities that the individuals in ; the pictures are engaged in are: agriculture, ; fishing, collection of honey, drawing water, ! gathering wood, mining, masonry, extraction i of salt, collection of rubber latex, gathering of resin from trees, converting wind into usable energy, transportation by pack animals.

Question 2.
What things will they obtain through these activities?
Answer:
They will obtain foodgrains, fish, honey, water, wood, minerals, house to live, salt, rubber, resin and energy which can be used for various purposes.

Question 3.
What are the animals in the picture doing?
Answer:
While the bullocks are ploughing the fields, j the donkey is used as a pack animal, for transporting heavy loads.

Question 4.
What is the use of the tall device in figure 8.12 raised on the ground?
Answer:
The tall device is a windmill which converts i wind into usable energy through the rotation ; of wheel which are adjustable. The energy thus i created can be used for a variety of purposes I such as generating electricity, grinding grains or spices, pumping water, sawing wood, aerating ponds, etc.

Question 5.
What is being loaded in the truck? What are we going to get from it?
Answer:
is being loaded into a truck from the mining area. We get minerals from the same.

Question 6.
Where are all these human activities being performed other than fishing?
Answer:
All these human activities are being performed on land.

Think a little!

Question 1.
List the various things for which we use water. Identify the things that lead to wastage of water.
Answer:
(a) Use of water.

• For agricultural and industrial purposes.
• For drinking and cooking.
• For personal hygiene.
• For our pets.
• Washing clothes and utensils.
• Cleaning houses, vehicles, etc.
• Watering plants in the garden.

(b) Identify the things that leads to wastage of water.

• When we pollute water.
• When we don’t save water by building dams, water wells and irrigation systems.
• When we waste water by using it excessively in flushes, bathrooms, etc.
• When we don’t use water-efficient faucets (taps), showers, etc.
• When we don’t repair faulty faucets.
• When we don’t close the tap when not required.
• When we use fountains and sprinklers in the gardens.

Question 2.
Name the different metals from which the things in your house are made. Make a chart of things and metals.
Answer:

Things	Metals
Cupboard	Stainless steel
Furniture	Iron
Idols of worship	Bronze
Lantern	Silver
Electrical wiring	Copper
Utensils	Copper and steel

Question 3.
List the occupations carried out on land.
Answer:

• Farming.
• Mining.
• Lumbering (Cutting down of trees).
• Extraction such as salt extraction, etc.
• Construction
• Beekeeping, etc.

Observe figure (Textbook Page no. 48) and answer the following questions:

Question 1.
Which vegetations do you find in the following location.
Answer:

Latitudes	Vegetation
(1) 90° Pole	Tundra
(2) 0° Equator	Equatorial evergreen
(3) 30°	Tropical Grasslands
(4) 60°	Mixed Forest
(5) 75° – 90°	Coniferous
(6) 15°	Deciduous

Question 2.
In which forest do we find tall trees?
Answer:
Equatorial Evergreen forest.

Question 3.
Name the grassland shown in the picture.
Answer:
Tropical grassland and temperate grassland.

Question 4.
Which vegetation indicate hot deserts?
Answer:
Thorny scrubs

Class 6 Geography Chapter 8 Natural Resources Textbook Questions and Answers

Complete the following statements using appropriate options:

Question 1.
_____ is a resource which never depletes. (Air, ‘Water, Animals)
Answer:
Air

Question 2.
Formation of mature soil is a very ______ process. (sudden, fast, slow)
Answer:
slow

Question 3.
Rock is a mixture of ________ (stone, black pebbles, minerals)
Answer:
minerals

Question 4.
The proportion of land on earth is ________%.
Answer:
29.20

Question 5.
_______ are the habitats for many animals. (Grassland, Vegetation,Thorny scrubs)
Answer:
Grassland

Match the pairs correctly:

Question 1.

Column A	Column B
(1) Horses and oxens	(a) used for hauling logs
(2) Cows and buffaloes	(b) transportation of goods
(3) Water available on the earth for use	(c) milk animals
(4) Settlements flourished	(d) 0.003%
	(e) Huang He

Answer:
1 – b
2 – c
3 – d
4 – e

Name the following:

Question 1.
The natural things that man uses:
Answer:
Natural resources.

Question 2.
A resource that is available in plenty:
Answer:
Air.

Question 3.
The basins along which man began to live a settled life in the past:
Answer:

• Huang He
• Sindhu (Indus)
• Nile and Euphrates

Question 4.
Habitats of animals:
Answer:
Forest or grasslands.

Question 5.
Any two products we get from animals:
Answer:

• Meat
• Eggs

Question 6.
Metallic minerals used for obtaining different metals:
Answer:

• Iron
• Bauxite

Question 7.
Non-metallic minerals used in obtaining various chemicals:
Answer:

• Gypsum
• Rock salt
• Calcite

Answer the following questions in one sentence each:

Question 1.
Why are natural resources invaluable?
Answer:
Most of the natural resources are limited in nature and therefore they are invaluable.

Question 2.
What do we need air for?
Answer:
We need air for various purposes right from breathing to burning.

Question 3.
Why do the farmers plough the soil?
Answer:
The farmers plough the soil to make the land cultivable.

Question 4.
How are plants classified?
Answer:
Plants are broadly classified into grass, shrubs and trees.

Give geographical reasons for the following statements:

Question 1.
Soil is a very important resource for agriculture.
Answer:

• The farmer ploughs the soil and makes the land cultivable.
• In this cultivable land, he grows various crops and fulfills his own and other’s need for food.
• For this purpose, he uses the ‘soil’ that is naturally available on land as a resource.
• Therefore soil is very important resource of agriculture.

Question 2.
Man began to live a settled life.
Answer:

• Man has successfully experimented with some grasses to obtain food grains.
• This helped him to avoid painful wandering for gathering food.
• Therefore, man began to lead a settled life.

Question 3.
It is necessary to conserve the natural resources.
Answer:

• Every living thing makes use of natural resources according to its need.
• However, man started using many of these resources for himself alone with the help of his intellectual power.
• Later, the increase in population and the greed of humans led to exploitative use of resources.
• This began to upset the balance in nature.
• So, it is necessary that man also must use the natural resources only according to his need, that is judiciously and thus conserve the natural resources.

Question 4.
Land is an invaluable resource.
Answer:

• All the activities of obtaining natural resources are being carried out on land.
• Land obtained at strategic location is used for construction as well as trade.
• Hence, land is an invaluable resource.

Answer the following questions in short:

Question 1.
Why are various living things found on the land in different proportions?
Answer:
Depending on the characteristics of land and climate, various living things are found on land in different proportions.

Question 2.
Which are the various geographical conditions which all living things try to adapt to?
Answer:
All living things try to adapt to various geographical conditions like rocky terrain, steep slopes, flat plains, mountainous regions, forest-covered areas, river basin, etc.

Balbharti Maharashtra State Board Class 6 Geography Solutions Chapter 7 Rocks and Rock Types Notes, Textbook Exercise Important Questions and Answers.

Maharashtra Board Class 6 Geography Solutions Chapter 7 Rocks and Rock Types

Class 6 Geography Chapter 7 Rocks and Rock Types Textbook Questions and Answers

B. Which of the following monuments are built in igneous rock?
(1) The Taj Mahal
(2) Fort Raigad
(3) The Red Fort
(4) Ellora Sculpture
Answer:
Ellora Sculpture

C. Find the differences between:

Question 1.
Igneous and sedimentary rocks
Answer:

Igneous rocks	Sedimentary rocks
(i) Igneous rocks are rocks formed by cooling and solidifying of molten materials. (ii) Igneous rocks are hard and homogeneous. (iii)  Examples: Basalt, pumice	(i) Rocks that are formed through deposition and compaction of sediments, especially rock particles transported by rivers, glaciers, wind, etc., are called sedimentary rocks. (ii) Sedimentary rocks are generally brittle and light weight. (iii) Examples: Sandstone, limestone, shale, corals

Question 2.
Sedimentary and metamorphic rocks
Answer:

Sedimentary rocks	Metamorphic rocks
(i) Rocks that are formed through deposition and compaction of sediments, especially rock particles transported by rivers, glaciers, wind, etc., are called sedimentary rocks.	(i) Rocks are formed due to the process of metamorphosis are called metamorphic rocks.
(ii) One may find fossils in sedimentary rocks. (iii) Sedimentary rocks are brittle and light weight. Examples: Shale, corals	(ii) Metamorphic rocks do not contain fossils. (iii) Metamorphic rocks are heavy and hard. Examples: Marble, slate

Question 3.
Igneous and metamorphic rocks
Answer:

igneous rocks	Metamorphic rocks
(i) Igneous rocks are rocks formed by cooling and solidifying of molten material. (ii) Igneous rocks are hard and homogeneous. (iii) Examples: Basalt, pumice	(i) Rocks formed due to the process of metamorphosis are called metamorphic rocks. (ii) Metamorphic rocks are heavy and hard. (iii) Examples: Gneiss, slate

D. Which types of rocks are predominantly found at the following locations?
(1) Central Maharashtra
(2) South Konkan
(3) Vidarbha
Answer:

Locations	Types of rocks
(1) Central Maharashtra	(a) Basalt
(2) South Konkan	(b) Laterite and granite
(3) Vidharbha	(c) Basalt, granite and sedimentary rocks

Activity:

Collect rock specimens from your surroundings and also during your travels. Classify them with the help of your teacher. Make a small museum of rocks for your school and place your specimens there. Keep a note of the place from where you have collected them. (See a specimen
display on page 65.)

Visit the historical sites in your surroundings, e.g., hill forts, masonry dams, land forts, bastions, wadas, temples, mosques, etc. and observe with the help of your teacher, the rock used for their construction.

Class 6 Geography Chapter 7 Rocks and Rock Types InText Questions and Answers

Do it yourself!

From the hills, river-beds or the land in your vicinity, collect rock specimens of different types, shapes, colours, etc. Observe the rock specimens and note down the following.

Question 1.
Place where the rock was found:
Answer:
Sahyadri mountain (Basalt)

Question 2.
Colours of the rock:
Answer:
Dark-black colour.

Question 3.
Spots on the rock and their colour:
Answer:
Dark grey to black.

Question 4.
Weight of the rock (estimated, heavy/light):
Answer:
Heavy.

Question 5.
Hardness of the rock, (hard/ brittle/medium):
Answer:
Hard.

Question 6.
Structure of the rock, (uniform grains/layers/ hollowness):
Answer:
Uniform grains.

Question 7.
Porosity of the rock, (porous/non-porous):
Answer:
Non-porous.

Observe the pictures given below and answer the questions:


Question 1.
What is the hill in ‘A’ made up of?
Answer:
Hill in ‘A’ is made up of soils and rocks.

Question 2.
What is being done in B’?
Answer:
In ’B’, the process of digging is shown. The land is dug and the rocks and soil that is extracted is loaded in to a truck.

Question 3.
What do we see in ‘C’?
Answer:
In ‘C’ we see pebbles and rocks of different types, shapes, colours, etc.

Question 4.
Is there any relationship between the three things shown above?
Answer:
Yes, these are all pictures of naturally occurring processes on land leading to rock and soil formation.

Question 5.
For what purpose do we use the things shown in A and C?
Answer:
We use things shown in A and C for construction purposes; coloured pebbles are used for decoration.

Use your brain power!

Question 1.
What rock was used for building the forts in Maharashtra? Why?
Answer:
Igneous rocks were used for building the forts in Maharashtra as they are hard, homogeneous and heavy.

Question 2.
Find the meaning of this line from a famous Marathi poem:
राकट देशा, कणखर देशा. दगडांच्या देशा
Answer:
The poet through this line conveys the message that our land is made up of hard rocks. We are a powerful entity and nothing can pose a threat to our Motherland. We can understand all odds.

Similarly like our terrains which are strong, the people of our country are also strong and invincible, incapable of being conquered.
We have imbibed the value of resilience and courage and the ability to withstand all challenges from our terrain.

What will you do?

Ajit is interested in sculpting. He wants to prepare a sculpture of Dr. APJ Abdul Kalam.
He cannot decide which rock he should use for this, igneous, sedimentary or metamorphic? What will be your advice?
Answer:
I would advise him to use a metamorphic rock like marble. Due to the translucent nature of the marble, it will give the sculpture a glow. Properties like softness and easy availability makes the metamorphic rock, marble an ideal choice. These rocks are heavy and hard. Hence, they are ideal for making sculptures.

Class 6 Geography Chapter 7 Rocks and Rock Types Additional Important Questions and Answers

Fill in the blanks choosing the correct options from the bracket:

Question 1.
Rocks are a mixture of different minerals formed by natural processes in the _____. (lithosphere, atmosphere, hydrosphere)
Answer:
lithosphere

Question 2.
There are ______ types of rocks according to their formation process. (four, three, five)
Answer:
three

Question 3.
When the molten material, known as magma within the crust and lava on the surface, cools down, it solidifies giving rise to ____ rocks. (Sedimentary, Igneous, Metamorphic)
Answer:
Igneous

Question 4.
We get fossils in ______ rocks. (Sedimentary, Igneous, Metamorphic)
Answer:
Sedimentary

Question 5.
The Maharashtra plateau and the Sahyadris are formed out of _______ rocks. (Sedimentary, Igneous, Metamorphic)
Answer:
Igneous

Question 6.
______ is a major example of igneous rocks. (Shale, Basalt, Corals)
Answer:
Basalt

Question 7.
Water percolating through rocks dissolves the soluble minerals leading to ________ of rocks, (weathering, compaction, increased porosity)
Answer:
weathering

Question 8.
_______ is a sedimentary rock. (Basalt, Sandstone, Pumice)
Answer:
Sandstone

Question 9.
The study of _______ provide information about life in that period. (metamorphosedrocks, Igneous rocks, fossils)
Answer:
fossils

Question 10.
_______ gets metamorphosed when it undergoes heavy pressure, and intense heat. (Coal,,Peat, Silica)
Answer:
Coal

Question 11.
_______ rock is found in the eastern parts and in South Konkap. (Granite,.Marble,Pumice)
Answer:
Granite

Question 12.
________ activity is concentrated in South Konkan and eastern Maharashtra. (Fishing, Mining, Construction)
Answer:
Mining

Question 13.
_____ is referred to as primary rocks. (Igneous rock, Sedimentary rock, Metamorphic rocks)
Answer:
Igneous rock

Question 14.
________ is a major example of igneous rock. (Basalt, Pumice, Sedimentary)
Answer:
Basalt

Question 15.
______ rocks are ‘formed due to compaction of material. (Metamorphic, Sedimentary, Igneous)
Answer:
Sedimentary

Question 16.
_________ rocks are heavy and hard. (Sedimentary, Metamorphic, Igneous)
Answer:
Metamorphic

Question 17.
When coal gets metamorphosed into ______ , its price increases. (garnet, diamond, opal)
Answer:
diamond

Question 18.
______ is found in South Konkan Maharashtra. (Granite, Laterite, Basalt)
Answer:
Laterite

Match the pairs correctly:

Question 1.

Column A	Column B
(1) Igneous rocks	(a) brittle and light weight
(2) Sedimentary rocks	(b) heavy and hard
(3) Metamorphic rocks	(c) hard and homogeneous

Answer:
1 – c
2 – a
3 – b

Complete the tabular form:

Original Rock	Metamorphosed Rock
Granite	_________
Basalt	__________
_________	Marble
Coal	___________
Sand Stone	__________
_________	Slate

Answer:

Original Rock	Metamorphosed Rock
Granite	Gneiss
Basalt	Amphibolite
Limestone	Marble
Coal	Diamond
Sand Stone	Quartizte
Shale	Slate

Name the following:

Question 1.
Two major rock-forming minerals:
Answer:
Silica, aluminium.

Question 2.
Hard and homogeneous rocks:
Answer:
Igneous rocks.

Question 3.
Two sedimentary rocks:
Answer:
Shale, corals.

Question 4.
Rocks which does not contain fossils:
Answer:
Metamorphic and Igneous rock

Question 5.
One use of diamonds:
Answer:
Ornament making.

Question 6.
One activity which leads to increased pressure and heat in that region:
Answer:
Volcanic eruption.

Question 7.
Rock found in South Konkan:
Answer:
Laterite.

Question 8.
Rocks that formed by metamorphosis:
Answer:
Metamorphic rocks.

Question 9.
Two metamorphosised rocks:
Answer:
Marble, Slate.

Question 10.
Two igneous rocks:
Answer:
Granite and Basalt.

State whether the following statements are true or false:

Question 1.
The properties of rocks depend on their constituent minerals and their proportion alone.
Answer:
False.

Question 2.
Silica is a rock forming mineral.
Answer:
True

Question 3.
One may find fossils in Igneous rocks.
Answer:
False

Question 4.
Weathering of rocks leads to its disintegration or decomposition.
Answer:
True

Question 5.
Sedimentary rocks are hard and homogeneous.
Answer:
False

Question 6.
Maharashtra has large reserves of mineral wealth.
Answer:
False

Question 7.
The Maharashtra plateau and the Sahyadris are formed out of igneous rocks.
Answer:
True

Question 8.
Most of the hill forts in Maharashtra do not have lakes or elephant yards.
Answer:
False

Question 9.
One can easily see layers in the sedimentary rocks.
Answer:
True

Question 10.
Sedimentary rocks are generally heavy weight.
Answer:
False

Question 11.
Metamorphic rocks do not contain fossils.
Answer:
True

Question 12.
Metamorphic rocks are brittle and lightweight.
Answer:
false

Answer the following questions in short:

Question 1.
What are rocks?
Answer:
Rocks are a mixture of different minerals formed by natural processes in the lithosphere. Rocks are found on land surface and also below it.

Question 2.
What do the properties of rocks depend on?
Answer:
The properties of rocks depend on the constituent minerals and their proportion as well as on the formation process. Silica, aluminium, magnesium and iron are the major rock-forming minerals.

Question 3.
What are the three types of rocks?
Answer:
Igneous rocks, Sedimentary rocks and Metamorphic rocks are the three types of rocks.

Question 4.
What are Igneous Rocks?
Answer:
When the molten material, known as magma within the crust and lava on the surface cools down, it solidifies giving rise to igneous rocks.

Question 5.
What information does the study of fossils provide?
Answer:
Study of fossils provide information about the life in the olden period.

Question 6.
Write any two characteristics of metamorphic rocks.
Answer:
Metamorphic rocks are heavy and hard.

Question 7.
When does coal get metamorphosed?
Answer:
When coal undergoes heavy pressure and intense heat it gets metamorphosed.

Question 8.
When does the price of coal increase?
Answer:
The price of coal increases when it gets metamorphosed into diamonds.

Question 9.
What is referred to as primary rocks?
Answer:
Rocks are formed out of the material from the interior of the earth, these are referred to as primary rocks.

Question 10.
What is called fossils?
Answer:
The buried remains of dead animals or plants embedded in the rocks and preserved petrified form are called fossils.

Give geographical reasons for the following statements:

Question 1.
Igneous rocks are also referred to as primary rocks.
Answer:
As Igneous rocks are formed out of the material from the interior of the earth, these rocks are also referred to as primary rocks.

Question 2.
Most of the hill forts in Maharashtra have lakes or elephant yards.
Answer:
(i) Hillforts in Maharashtra are old quarry sites from which stone or other materials have been extracted for the construction of the fort and other buildings.

(ii) In the pits and dugouts left behind after rock extraction, water was allowed to accumulate and these lakes, banks, etc., were created.

(iii) Therefore, most of the hill forts in Maharashtra have lakes or elephant yards.

Question 3.
Weathering of rocks occurs.
Answer:

• Due to continuous variations in temperature, rocks develop cracks.
• Similarly, the water percolating through rocks dissolves the soluble minerals.
• This leads to the weathering of rocks.

Question 4.
One may find fossils in sedimentary rocks.
Answer:

• One can easily see layers in sedimentary rocks.
• While layers are getting deposited, the remains of the dead animals or plants get buried in these layers at times.
• Therefore, one may find fossils in sedimentary rocks.

Question 5.
Changes in nature, as well as the chemical composition of the original rocks, is witnessed.
Answer:

• Volcanic activity and other earth movements constantly take place on the earth.
• While these are occurring, the igneous and sedimentary rocks in that region are subjected to tremendous pressure and heat.
• This leads to changes in nature as well as the chemical composition of the original rocks.

Question 6.
Maharashtra does not have a large reserve of mineral wealth.
Answer:
Maharashtra does not have a large reserve of mineral wealth due to the thick and extensive layers of basalt rocks.

Answer the following questions in detail:

Question 1.
What leads to the development of sedimentary rocks?
Answer:

• Due to continuous variations in the temperature, rocks develop cracks.
• Similarly, the water percolating through rocks dissolves the soluble minerals leading to the weathering of rocks.
• They get disintegrated or decomposed i.e. reduced to pieces.
• These rock particles get transported by rivers, glaciers, wind, etc. towards low lying area and are deposited there.
• One after the other, layers of sediments gets deposited in this way.
• The upper layers exert heavy pressure on the lower layers.
• This leads to compaction of materials and development of sedimentary rocks.

Question 2.
How are Metamorphic rocks formed?
Answer:

• Volcanic activity and other earth movements | constantly take place on the earth.
• While these are occurring, the igneous or sedimentary rocks in that region are subjected to tremendous pressure and heat.
• This leads to changes in the nature as well as the chemical composition of original rocks.
• The crystals in the original rock gets recrystalized, the rock gets metamorphosed.
• The rocks formed through such a process are ! called Metamorphic rocks.

Question 3.
How is sand that flows in a river formed? Collect some information about where the sand comes from.
Answer:

• Moving streams are so powerful that it can wear away soil rocks.
• Rocks on higher land get eroded due to the strong current of the streams and they in turn get carried away into the sea.
• Silt too is brought down from the mountain top from where the streams originate.
• Most of the sand in the river is silt carried by the streams and the weather material from inland rocks transported by the streams.
• The moving of soil and rock with the stream, termed as erosion can be summed up as the cause of sand formation in a river.

Balbharti Maharashtra State Board Class 8 Science Solutions Chapter 13 Chemical Change and Chemical Bond Notes, Textbook Exercise Important Questions and Answers.

Maharashtra State Board Class 8 Science Solutions Chapter 13 Chemical Change and Chemical Bond

Class 8 Science Chapter 13 Chemical Change and Chemical Bond Textbook Questions and Answers

1. Complete the statement by filling the gaps using appropriate term from the terms given in the brackets:
(slow, coloured, arrow, fast, smell, milky, physical, product, chemical, reactant, covalent, ionic, octet, duplet, exchange, sharing, equality sign)

Question a.
An ……….. is drawn in between the reactants and products while writing the equation for a chemical reaction.
Answer:
An arrow is drawn in between the reactants and products while writing the equation for a chemical reaction.

Question b.
Rusting of iron is a ……….. chemical change.
Answer:
Rusting of iron is a slow chemical change.

Question c.
The spoiling of food is a chemical change which is recognized from the generation of certain …………. due to it.
Answer:
The spoiling of food is a chemical change which is recognized from the generation of certain smell due to it.

Question d.
A colourless solution of calcium hydroxide in a test tube turns ………….. on blowing in it through a blow tube for some time.
Answer:
A colourless solution of calcium hydroxide in a test tube turns milky on blowing in it through a blow tube for some time.

Question e.
The white particles of baking soda disappear when put in lemon juice. This means that it is a ……….. change.
Answer:
The white particles of baking soda disappear when put in lemon juice. This means that it is a chemical change.

Question f.
Oxygen is a …………….. in respiration.
Answer:
Oxygen is a reactant in respiration.

Question g.
Sodium chloride is …………… compound while hydrogen chloride is compound.
Answer:
Sodium chloride is ionic compound while hydrogen chloride is covalent compound.

Question h.
Electron …………….. is complete in each hydrogen in a hydrogen molecule.
Answer:
Electron duplet is complete in each hydrogen in a hydrogen molecule.

Question i.
Chlorine (Cl₂) molecule is formed by ………….. of electrons between two chlorine atoms.
Answer:
Chlorine (Cl₂) molecule is formed by sharing of electrons between two chlorine atoms.

2. Explain by writing a word equation. 

Question a.
Respiration is a chemical change.
Answer:
Respiration is a biological process, in this process air is inhaled, oxygen present in this inhaled air reacts with glucose present in the cells of the body forming carbon dioxide and water. Moreover, we cannot obtain glucose and oxygen from carbon dioxide and water. Hence, respiration is a chemical change.
Word equation:

Question b.
Hard water gets softened on mixing with a solution of washing soda.
Answer:
Hard water does not form lather with soap and is brackish to taste. This is because hard water contains the chloride and sulphate salts of calcium and magnesium in dissolved state. When a solution of washing soda is added to hard water, it forms a precipitate of calcium carbonate and magnesium carbonate, which is removed by filtration thus water is softened.
Word equation:

Question c.
Limestone powder disappears on adding to dilute hydrochloric acids.
Answer:
In the reaction of dil. HCl and limestone powder (CaCO₃), limestone disappears slowly and carbon dioxide (CO₂) liberates slowly.
Word equation:

Question d.
Bubbles are seen on adding lemon juice to baking soda.
Answer:
When baking soda is added to lemon juice a chemical change takes place in citric acid present in the lemon juice and carbon dioxide gas is formed. Word equation:

This is a neutralization reaction.

3. Match the pairs.

Question a.

Column I	Column II
1. Photosynthesis	a. Tendency to lose electrons
2. Water	b. Reactant in combustion process
3. Sodium chloride	c. Chemical change
4. Dissolution of salt in water	d. Covalent bond
5. Carbon	e. Ionic bond
6. Fluorine	f. Physical change
7. Magnesium	g. Tendency to form anion

Answer:

Column I	Column II
1. Photosynthesis	c. Chemical change
2. Water	d. Covalent bond
3. Sodium chloride	e. Ionic bond
4. Dissolution of salt in water	f. Physical change
5. Carbon	b. Reactant in combustion process
6. Fluorine	g. Tendency to form anion
7. Magnesium	a. Tendency to lose electrons

4. Show with the help of diagram of electronic configuration how the following compounds are formed from the constituent atoms.

Question a.
Sodium Chloride:

Answer:
1. Sodium has atomic number 11 and electronic configuration 2, 8, 1.
2. Sodium atom has 1 electron in its outermost shell.

3. It loses one electron from its outermost shell, i.e., M shell. Then its L shell becomes the outermost shell with a stable octet. The nucleus of sodium atom has 11 protons but the number of electrons in the atom has become 10. So, there is a net unit positive charge giving a sodium cation (Na⁺).

4. On the other hand, chlorine has electronic configuration 2, 8, 7. Chlorine atom has 7 electrons in its outermost shell and requires one electron to complete its octet.
5. Thus, the electron lost by sodium is taken up by chlorine.

6. When chlorine atom gains one electron, octet of chlorine is completed and its K, L, M shells have together 18 electrons and the nucleus has 17 protons. This leads to the formation of an ion (CP).

7. Thus, a chlorine atom accepts one electron from a sodium atom and consequently a chloride ion with one unit negative charge and a sodium ion with one unit positive charge are formed.

8. Sodium and chloride ions, being oppositely charged, attract each other due to the electrostatic force of attraction. An ionic bond is formed and this results in the formation of sodium chloride (NaCl) molecule.

Question b.
Potassium fluoride:
Answer:
1. Potassium has atomic number 19 and electronic configuration 2, 8, 8, 1.
2. Potassium atom has 1 electron in its outermost shell.

3. It loses one electron from its outermost shell, i.e. N shell. Then its M shell becomes the outermost shell with a stable octet. The nucleus of potassium atom has 19 protons but the number of electrons in the atom has become 18. So there is a net unit positive charge giving a potassium cation (K⁺).

4. On the other hand, fluorine has electronic configuration 2, 7. Fluorine has 7 electrons in the outermost shell and requires one electron to complete its octet.

5. Thus, the electron lost by potassium is taken up by chlorine.

6. When fluorine atom gains one electron, octet of fluorine is completed, its K and L shells have together 10 electrons and the nucleus has 9 protons. This leads to the formation of an ion (F^–).

7. Thus, a fluorine atom accepts one electron from a potassium atom and consequently a fluoride ion with one unit negative charge and a potassium ion with one unit positive charge are formed.

8. Potassium and fluoride ions, being oppositely charged, attract each other due to electrostatic force of attraction. An ionic bond is formed and this results in the formation of potassium fluoride (KF) molecule.

Question c.
Water:
Answer:

1. Hydrogen has atomic number 1 and electronic configuration 1.
2. Hydrogen has 1 electron in its K shell.

3. Oxygen has atomic 8 and electronic configuration 2, 6. There are 6 electrons in the valence shell of oxygen atom. It means that the electron octet in oxygen is short of two electrons and the valency of oxygen is two.

4. In the H₂O molecule, the oxygen atom complete its octet by sharing two electrons one each with two hydrogen atoms, thus, forming two covalent bonds. While this happens, the duplets of two hydrogen atoms are completed.

Question d.
Hydrogen chloride:
Answer:
1. Hydrogen has atomic number 1 and electronic configuration 1, that means it has 1 electron in its K shell and its duplet is short of one electron therefore, the valency of hydrogen is one.

2. On the other hand, chlorine has electronic configuration 2, 8, 7. Chlorine atom has 7 electrons in its outermost shell and requires one electron to complete its octet.

3. The two atoms, hydrogen and chlorine share one electron with each other. As a result, the electron duplet of hydrogen and octet of chlorine is complete and a covalent band is formed between them.

Can you recall?

Question a.
What are the methods of classification of changes?
Answer:
The methods of classification of changes: Physical change and chemical change.

Question b.
What is the difference between physical and chemical change?
Answer:

1. In physical change, the composition of substance does not change. No new substance is formed.
2. In chemical change, the composition of compounds change and new compounds are formed.

Question c.
Classify the following changes into physical and chemical change. Ripening of mango, melting of ice, boiling of water, dissolution of salt in water, Ripening of banana, fragrance on ripening fruit, darkening of a cut potato, bursting of an inflated balloon, sound of bursting fire cracker, foul smell from a portion of spoiled food.
Answer:

• Physical change: Melting of ice, boiling of water, dissolution of salt in water.
• Chemical change: Ripening of mango, ripening of banana, fragrance of ripening fruit, darkening of a cut potato, bursting of an inflated balloon, sound of bursting firecracker, foul smell from a spoiled food.

Project:

Question a.
Prepare a list of the chemical changes that occur in your house and surroundings and discuss these in the class.

Class 8 Science Chapter 13 Chemical Change and Chemical Bond Important Questions and Answers

Fill in the blanks:

Question 1.
……………. is a continuously occurring biological process.
Answer:
Respiration is a continuously occurring biological process.

Question 2.
The reaction between citric acid and sodium bicarbonate is a ……………. reaction.
Answer:
The reaction between citric acid and sodium bicarbonate is a neutralization reaction.

Question 3.
Combustion of fuel is a ………… and ……………. chemical change.
Answer:
Combustion of fuel is a fast and irreversible chemical change.

Question 4
Electronic configuration of sodium is …………….
Answer:
Electronic configuration of sodium is 2, 8, 1.

Question 5.
Electronic configuration of chlorine is …………….
Answer:
Electronic configuration of chlorine is 2, 8, 7.

Question 6.
A chemical bond formed by sharing of valence electrons of two atoms with each other is called a …………….
Answer:
A chemical bond formed by sharing of valence electrons of two atoms with each other is called a covalent bond.

Question 7.
Hard water contains the chloride and sulphate salts of ……………. and ……………. in dissolved state.
Answer:
Hard water contains the chloride and sulphate salts of calcium and magnesium in dissolved state.

Question 8.
Electronic configuration of fluorine is …………….
Answer:
Electronic configuration of fluorine is 2, 7.

Question 9.
Green plants perform ……………. in sunlight.
Answer:
Green plants perform photosynthesis in sunlight.

Question 10.
Melting of ice is a ……………. change.
Answer:
Melting of ice is a physical change.

Question 11.
The chloride ion has a ……………. charge.
Answer:
The chloride ion has a negative charge.

Question 12.
A covalent bond between two atoms is also represented by ……………. joining their symbols.
Answer:
A covalent bond between two atoms is also represented by dash joining their symbols.

Rewrite the following statements by selecting the correct options:

Question 1.
Sodium atoms and sodium ions ………….. .
(a) are chemically the same
(b) have the same number of protons
(c) have the same number of electrons
(d) form covalent bond
Answer:
(b) have the same number of protons

Question 2.
An ionic bond is formed when …………….. .
(a) two metallic elements react
(b) two nonmetallic elements react
(c) a metallic element reacts with a non-metallic element
(d) a pair of elements react
Answer:
(c) a metallic element reacts with a non-metallic element

Question 3.
…………….. tries to establish the duplet state in its outermost orbit by sharing electrons.
(a) Sodium
(b) Potassium
(c) Hydrogen
(d) Magnesium
Answer:
(c) Hydrogen

Question 4.
…………… is an electron donor.
(a) Helium
(b) Iodine
(c) Chlorine
(d) Magnesium
Answer:
(d) Magnesium

Question 5.
………………. combine to form an ionic compound.
(a) Hydrogen and chlorine
(b) Hydrogen and oxygen
(c) Potassium and chlorine
(d) Nitrogen and oxygen
Answer:
(c) Potassium and chlorine

Question 6.
……………. is an example of chemical change.
(a) Magnetism of iron
(b) Rusting of iron
(c) Heating of iron till it becomes red hot
(d) Dissolution of salt in water
Answer:
(b) Rusting of iron.

State whether the following statements are True or False. (If a statement is false, correct it and rewrite it.)

Question 1.
The preparation of cold drink soda- lemon is a physical change.
Answer:
False. [The preparation of cold drink soda-lemon is a chemical change.]

Question 2.
Hard water contains the chloride and sulphate salts of calcium and magnesium in dissolved state.
Answer:
True.

Question 3.
Combustion of fuel is a fast and irreversible man-made chemical change.
Answer:
True.

Question 4.
Photosynthesis reaction is a man-made chemical change.
Answer:
False. [Photosynthesis reaction is a natural chemical change.]

Question 5.
The atoms with incomplete electron octet/duplet form chemical bonds.
Answer:
True.

Question 6.
Electronic configuration of chlorine is 2, 8, 6.
Answer:
False. (Electronic configuration of chlorine is 2, 8, 7.)

Question 7.
One ionic bond is formed due to the electrical change +1 or -1 on an ion.
Answer:
True.

Question 8.
H₂O Molecule is an ionic compound.
Answer:
False. (H₂O molecule is a covalent compound.)

Question 9.
The bond between two chlorine atoms is a covalent band.
Answer:
True.

Question 10.
Arrow indicates the direction of the reaction.
Answer:
True.

Consider the correlation between the words of the first pair, match the third word/words with the most appropriate answer:

Question 1.
K : 2, 8, 8, 1 : : Mg : ………………
Answer:
2, 8, 2

Question 2.
MgCl₂ : Ionic bond : : CaO : ……………..
Answer:
Covalent bond

Question 3.
Photosynthesis : Natural chemical change : : Cold drink, soda lemon : ………
Answer:
Man-made chemical change

Question 4.
Respiration: Glucose + Oxygen : : Neutralization : ………….
Answer:
Acid + alkali.

Match the columns:

Question 1.

Column I	Column II
1. Respiration	a. Potassium and fluorine
2. Acid + Base	b. Glucose and oxygen
3. Photosynthesis	c. Carbon dioxide and water
4. Ionic bond	d. Salt and water

Answer:

Column I	Column II
1. Respiration	c. Carbon dioxide and water
2. Acid + Base	d. Salt and water
3. Photosynthesis	b. Glucose and oxygen
4. Ionic bond	a. Potassium and fluorine

Define the following:

• Chemical change: In a chemical change, the chemical composition of the original matter changes and new substances having different properties and different chemical composition are formed.
• Ionic bond: The chemical bond formed due to an electrostatic force of attraction between the oppositely charged cation and anion is called an ionic bond or an electrovalent bond.
• Covalent bond: The chemical bond formed by sharing of valence electrons of two atoms with each other is called a covalent bond.

Answer the following questions in one sentence each:

Question 1.
Name the reactants in respiration.
Answer:
Glucose and oxygen are the reactants in respiration.

Question 2.
Name the products of respiration.
Answer:
Carbon dioxide and water are the products of respiration.

Question 3.
Name the reactants in photosynthesis.
Answer:
Carbon dioxide and water are the reactants in photosynthesis.

Question 4.
Name the products of photosynthesis.
Answer:
Glucose and oxygen are the products of photosynthesis.

Question 5.
Name the salts present in hard water.
Answer:
Salts present in hard water are calcium chloride, magnesium chloride, calcium sulphate and magnesium sulphate.

Question 6.
Give two examples of ionic compounds.
Answer:
Ionic compounds: Sodium chloride (NaCl), Potassium fluoride (KF).

Question 7.
Give two examples of covalent compounds.
Answer:
Covalent compounds: Hydrogen (H₂), Water (H₂O).

Question 8.
Name an acid used for cleaning Shahabad tile.
Answer:
An acid used for cleaning Shahabad tile is dilute hydrochloric acid (HCl).

Question 9.
Write a chemical equation for combustion of fuel.
Answer:
Chemical equation:
C + O₂ → CO₂

Question 10.
Write a chemical equation for photosynthesis.
Answer:
Chemical equation:

Answer the following questions:

1. Explain by writing a word equation.

Question 1.
Combustion of fuel is a fast and irreversible chemical change.
Answer:
Wood, coal, petrol or cooking gas are burnt for producing energy. Carbon is the common substance that burns in all these fuels. The product carbon dioxide is formed when carbon combines with oxygen in the air during the combustion process. We cannot obtain fuel from carbon dioxide by employing any other method. Properties of carbon dioxide are altogether different from those of fuel. Hence, this change is a irreversible chemical change.
Word equation:
Carbon + Oxygen → Carbon dioxide

Question 2.
Dilute hydrochloric acid is used for cleaning Shahabad tiles.
Answer:
The main constituent of Shahabad tile is calcium carbonate. During its cleaning with hydrochloric acid, the upper layer of the tile reacts with hydrochloric acid and three products are formed. One of them is calcium chloride, which being soluble in water, gets washed away with water. The second product is carbon dioxide, it mixes with air. The third product is water.
Word equation:

2. Write a chemical equation (unbalanced) for the following reactions:

Question 1.

Answer:
Chemical equation:
CO₂ + Ca(OH)₂ → CaCO₃ + H₂O

Question 2.

Answer:
Chemical equation:
CaCO₃ + HCl → CaCl₂ + CO₂ + H₂O

Question 3.
Magnesium salts during the softening of hard water.

Answer:
Chemical equation:
MgCl₂ + Na2CO₃ → MgCOg + 2NaCl

3. Show with the help of diagram of electronic configuration how the following compounds are formed from the constituent atoms.

Question 1.
Hydrogen molecule:
Answer:
1. Hydrogen has atomic number 1 and electronic configuration 1. That means it has 1 electron in its K shell and its duplet is short of one electron therefore, the valency of hydrogen is one.

2. The two atoms of hydrogen are identical, they share their electrons with each other.
3. As a result, the electron duplet of both the hydrogen atoms is complete and a covalent band is formed between them.

4. There is one covalent bond between the component atoms H and Cl of the molecule HCl. Use this information to represent the formation of HCl molecules from H and Cl atoms diagrammatically.
(Use your brainpower)
Answer:
Hydrogen chloride:
1. Hydrogen has atomic number 1 and electronic configuration 1, that means it has 1 electron in its K shell and its duplet is short of one electron therefore, the valency of hydrogen is one.

2. On the other hand, chlorine has electronic configuration 2, 8, 7. Chlorine atom has 7 electrons in its outermost shell and requires one electron to complete its octet.

3. The two atoms, hydrogen and chlorine share one electron with each other. As a result, the electron duplet of hydrogen and octet of chlorine is complete and a covalent band is formed between them.

5. Show the formation of the following ionic compounds from the corresponding elements using two methods namely, numerical and diagrammatic representation of electronic configuration.
(a) K⁺ F^–, from 19K and 9F, (b) Ca²⁺ O^2- from ₂₀Ca and ₈O.
(Use your brainpower)
Answer:
(a) K⁺F^– from ₁₉K and ₉F
Potassium fluoride:
1. Potassium has atomic number 19 and electronic configuration 2, 8, 8, 1.
2. Potassium atom has 1 electron in its outermost shell.

3. It loses one electron from its outermost shell, i.e. N shell. Then its M shell becomes the outermost shell with a stable octet. The nucleus of potassium atom has 19 protons but the number of electrons in the atom has become 18. So there is a net unit positive charge giving a potassium cation (K⁺).

4. On the other hand, fluorine has electronic configuration 2, 7. Fluorine has 7 electrons in the outermost shell and requires one electron to complete its octet.

5. Thus, the electron lost by potassium is taken up by chlorine.

6. When fluorine atom gains one electron, octet of fluorine is completed, its K and L shells have together 10 electrons and the nucleus has 9 protons. This leads to the formation of an ion (F^–).

7. Thus, a fluorine atom accepts one electron from a potassium atom and consequently a fluoride ion with one unit negative charge and a potassium ion with one unit positive charge are formed.

8. Potassium and fluoride ions, being oppositely charged, attract each other due to electrostatic force of attraction. An ionic bond is formed and this results in the formation of potassium fluoride (KF) molecule.

(b) Ca²⁺O^2- from ₂₀Ca and ₈O.

Distinguish between the following:

Question 1.
Physical change and Chemical change:
Answer:

Physical change	Chemical change
1. In this change, the composition of the substance does not change. No new substance is formed.	1. In this change, the composition of the compounds change and new compounds are formed.
2. In this case, physical properties such as state, colour, density, etc. are changed.	2. In this case, physical and chemical properties are entirely changed.
3. This change is temporary.	3. This change is permanent.
4. In this case, the original substance can be recovered by simple means or by merely reversing the process.	4. In this case, the original substance cannot be recovered by easy means or by reversing the process.

Question 2.
Ionic bond and Covalent bond:
Answer:

Ionic bond	Covalent bond
1.  Ionic bond is formed due to the transfer of electrons from one atom to another.	1. Covalent bond is formed due to the sharing of electrons between two or more atoms.
2. Atoms of metals and nonmetals combine to form ionic bonds.	2. Atoms of nonmetals combine to form covalent bonds.
3. Molecules of the compounds formed due to ionic bond split up into ions in aqueous solution.	3. Molecules of the compounds formed due to covalent bond so not split up into ions in a solution.

Give scientific reasons:

Question 1.
Ionic compounds are formed due to the combination of metallic and nonmetallic atoms.
Answer:
Metallic atoms have a tendency to lose electrons from their outermost orbits to establish the octet state in their penultimate orbits. Conversely, nonmetallic atoms gain electrons to establish the octet state of their outermost orbits.

When a metallic atom and a nonmetallic atom come close together, the metallic atom loses electrons and gets c converted into positively charged ion, while the nonmetallic’ atom gets converted into negatively charged ions so formed, develop an ionic bond and this results in the formation of an ionic compound. Hence, ionic compounds are formed due to the combination of metallic and nonmetallic atoms.

Activity-based questions:

Activity 1:

Take the lemon juice in a clean glass. Take two drops of the lemon juice in a spoon and taste. Add a pinch of baking soda in the glass of lemon juice. Did you notice bubbling around the particles of soda? Did you hear a sound on taking your ear near the glass? Now again taste it. Did it taste as sour as it was in the beginning? (Above activity is to be done using clean apparatus and edible material. Then only it is possible to test the ’taste’, otherwise keep in mind that the testing of ‘taste’ cannot be done.)

Activity 2:
Take some freshly prepared lime water (solution of calcium hydroxide) in a test tube. Keep on blowing in it with a blow tube. What is seen after some time? Did the colourless lime water turn milky? After some more time you will find that a white insoluble solid settles at the bottom of the test tube. This is a precipitate of calcium carbonate. The turning lime water milky means that the blown gas mixed in it was carbon dioxide.

Write a chemical equation for the above word equation.
Chemical equation:
CO₂ + Ca(OH)₂ → CaCO₃ + H₂O

Balbharti Maharashtra State Board Class 6 History Solutions Chapter 1 The Indian Subcontinent and History Notes, Textbook Exercise Important Questions and Answers.

Maharashtra Board Class 6 History Solutions Chapter 1 The Indian Subcontinent and History

Class 6 History Chapter 1 The Indian Subcontinent and History Textbook Questions and Answers

1. Answer the following in one sentence:

Question 1.
What is history?
Answer:
History is a coherent account of the significant past events in the progress of human culture.

Question 2.
Where do human settlements flourish?
Answer:
Human settlements have flourished wherever the means of living are plentiful.

Question 3.
What do the people in the hilly region j depend on for their food?
Answer:
In the hilly regions people depend more on hunting and gathering for their food.

Question 4.
Which was the earliest civilization in India?
Answer:
The Harappan civilization was the earliest civilization in India.

2. Answer the following questions in short:

Question 1.
What does human life depend on?
Answer:
Human life in any region depends to a large extent on its geographical characteristics, diet, clothing, housing and occupation.

Question 2.
What features of our surroundings form the means of our livelihood?
Answer:
The climate, rainfall, agricultural produce, flora and fauna of the region where we live form the source or means of our livelihood.

Question 3.
Which region is known as the Indian subcontinent?
Answer:
Afghanistan, Pakistan, Nepal, Bhutan, Bangladesh, Sri Lanka and India together form the region known as south Asia. Considering the expanse and significance of India in this region, it is also known as the Indian subcontinent.

3. Give reasons:

Question 1.
There is a close relation between history and geography.
Answer:

• Time, place, society and individuals are four major pillars without which history cannot be written.
• Of these four components ‘place’ is related to geography or geographical conditions.
• This makes history and geography inseperable i.e. very closely related.

Question 2.
People are forced to leave their settlements.
Answer:

• Sometimes reasons like degradation of the environment, drought, invasion, etc. leads to scarcity of means.
• Therefore, people are forced to leave their settlements in their fight for survival.

4. Explain the difference in the human life in the hilly regions and that on the plains.
Answer:

Human life in the Hilly region	Human life in the Plains
(1) Human life was very strenuous	(1) Life was more comfortable.
(2) Land was not fertile. therefore no So agriculture was wcarried on.	(2) Land was very Fertile So agriculture   was carried on.
(3) Grains and vegetables Grains and are scarce.	(3) Grains and vegetables are found in plenty
(4) They depend on hunting and gathering  for their food.	(4) They do not depend on hunting and gathering for their food.

5. Observe the physical map of India and answer the questions based on it:

Question 1.
Which mountain ranges lie in the north of India?
Answer:
The Hindukush and the Himalayan mountain ranges.

Question 2.
Which are the routes to India from the north-east?
Answer:
The route to India from the north east is by sea.

Question 3.
Where do the Ganga and Brahmaputra meet?
Answer:
The Ganga and Brahmaputra meet in Bangladesh.

Question 4.
Name the islands to the east of the Indian peninsula.
Answer:
The Andaman and Nicobar islands are the Indian islands to the east of the Indian peninsula.

Question 5.
In which part of India do we see the Thar Desert?
Answer:
We see the Thar Desert in the north western part of India.

Activity:

• Obtain information about the lakes or reservoirs in your locality.
• Show the following on a world map :
  1. The Himalaya Mountain
  2. The Silk Road
  3. Arabia

Class 6 History Chapter 1 The Indian Subcontinent and History Additional Important Questions and Answers

Complete the sentence by choosing the correct option:

Question 1.
________ is a coherent account of the significant past events in the progress of human culture.
(a) History
(b) Geography
(c) Civics
Answer:
History

Question 2.
Not much fertile land is available in the ______ region.
(a) plains
(b) hilly
(c) plateau
Answer:
hilly

Question 3.
Grains and vegetables are _______ in the hilly areas.
(a) scarce
(b) plenty
(c) moderate
Answer:
scarce

Question 4.
In the ______ regions, people depend more on hunting and gathering for their food.
(a) plateau
(b) plains
(c) hilly
Answer:
hilly

Question 5.
Human settlements have flourished wherever the means of living are _______.
(a) scarce
(b) plentiful
(c) moderate
Answer:
plentiful

Question 6.
_____ lies to the north of India.
(a) Andaman
(b) Western Ghats
(c) Himalayas
Answer:
Himalayas

Question 7.
_____ lies to the east of India.
(a) Bay of Bengal
(b) Eastern ghats
(c) Lakshadweep
Answer:
Bay of Bengal

Question 8.
_________ lies to west of India.
(a) Himalayas
(b) Arabian sea
(c) Brahmaputra
Answer:
Arabian sea

Question 9.
______ lies to the south of India.
(a) Indian Ocean
(b) Arabian Sea
(c) Pacific Ocean
Answer:
Indian Ocean

Question 10.
The Hindukush and Himalayan ranges have created an impenetrable wall on the nothern side of the ________ subcontinent.
(a) Indian
(b) Foreign
(c) Asian
Answer:
Indian

Question 11.
There is a land route through the Khyber and Bolan passes in the ______ mountains.
(a) Himalayan
(b) Satpuda
(c) Hindukush
Answer:
Hindukush

Question 12.
The _____ desert spreads across Rajasthan, Haryana and some parts of Gujarat.
(a) Bhor
(b) Thar
(c) Arabian
Answer:
Thar

Question 13.
The _______ river that originates in Himachal Pradesh reaches the Thar desert.
(a) Ganga
(b) Sindhu
(c) Ghaggar
Answer:
Ghaggar

Question 14.
A region that is bound by sea on three sides is called a ______.
(a) peninsula
(b) plateau
(c) island
Answer:
peninsula

Question 15.
A major part of the Indian peninsula is occupied by the_______ plateau.
(a) Maharashtra
(b) Bengal
(c) Deccan
Answer:
Deccan

Question 16.
The mountain ranges of the Vindhya and Satpuda are located to the of the ________ Deccan Plateau.
(a) east
(b) north
(c) west
Answer:
north

Question 17.
Deccan plateau was a part of the ______ empire, the largest in ancient India.
(a) Maurya
(b) Gupta
(c) Chola
Answer:
Maurya

Question 18.
Lakshadweep is a group of Indian islands in the _____ Sea.
(a) Red
(b) Dead
(c) Arabian
Answer:
Arabian

Question 19.
The Harappan civilization had spread mainly in the ________ part of the Indian subcontinent.
(a) southeastern
(b) northwestern
(c) southwestern
Answer:
north western

Match the following:

Question 1.

Column (A)	Column (B)
(1) Himalayas	(a) South
(2) Indian Ocean	(b) East
(3) Arabian Sea	(c) North
(4) Bay of Bengal	(d) West

Answer:
1 – c
2 – a
3 – d
4 – b

Question 2.

Column (A)	Column (B)
(1) China	(a) Deccan plateau
(2) Vindhya range	(b) Not a part of Indian subcontinent
(3) Bangladesh	(c) In Bay of Bengal
(4) Andaman and Nicobar islands	(d) In the Hindukush mountains
(5) Khyber and Bolan passes	(e) Part of Indian subcontinent

Answer:
1 – b
2 – a
3 – e
4 – c
5 – d

Answer the following in one sentence:

Question 1.
Give the four major pillars without which history could not have been written.
Answer:
Time, place, society and individuals are the four major pillars of history, without which history could not have been written.

Question 2.
What has created an impenetrable wall on j the northern side of the Indian subcontinent? j
Answer:
Two mountain ranges, the Hindukush and Himalayan ranges have created an impenetrable wall on the northern side of the Indian subcontinent.

Question 3.
Which passes form a route in the Hindukush mountains?
Answer:
The Khyber and the Bolan passes form a land route in the Hindukush mountains.

Question 4.
What is known as ‘Hakra’ in Pakistan?
Answer:
The Ghaggar river that originates in Himachal Pradesh reaches the Thar desert. It is known as ‘Hakra’ in Pakistan.

Question 5.
Which plateau occupies a major part of the Indian peninsula?
Answer:
The Deccan plateau occupies a major part of the Indian peninsula.

Question 6.
Which mountain range is to the north of the Deccan plateau?
Answer:
The Vindhya and Satpuda mountain ranges are located to the north of the Deccan plateau.

Question 7.
Name the Indian islands in the Bay of Bengal.
Answer:
Andaman and Nicobar are the Indian islands in the Bay of Bengal.

Question 8.
Which manuscript mentions the Indian islands?
Answer:
The manuscript ‘Periplus of the Erythrean Sea’ or ‘Handbook of the Red Sea’ by an unknown Greek sailor, makes a mention of Indian islands.

Question 9.
Which two ancient cities are in today’s Pakistan?
Answer:
The cities of Harappa and Mohenjo-daro are in today’s Pakistan.

Answer the following questions in short:

Question 1.
State the extent of our country, India.
Answer:
Our country India, extends far and wide:

• To its north lies the Himalayas.
• To the east, the Bay of Bengal.
• To the west, the Arabian Sea.
• And to the south, the Indian ocean.
• Except for the islands of Andaman, Nicobar and Lakshadweep, the rest of the country is contiguous.

Question 2.
Describe the trade route from China to Arabia.
Answer:

• There is a land route through the Khyber and Bolan passes in the Hindukush mountains.
• This land route was connected to an ancient trade route.
• The trade route from China in the east passed through central Asia and reached Arabia in the west.

Give reasons:

Question 1.
The trade route from west to east was also called the silk route.
Answer:

• Silk was the main commodity exported to the western countries using this trade route.
• Therefore this trade route from west to east was called the ‘silk route’ or ‘silk road’.

Balbharti Maharashtra State Board Class 6 Geography Solutions Chapter 6 Importance of Oceans Notes, Textbook Exercise Important Questions and Answers.

Maharashtra Board Class 6 Geography Solutions Chapter 6 Importance of Oceans

Class 6 Geography Chapter 6 Importance of Oceans Textbook Questions and Answers

A. Find the odd man out:

Question 1.
Shell, fish, crab, ship
Answer:
ship

Question 2.
Arabian Sea, Mediterranean Sea, Dead Sea, Caspian Sea
Answer:
Dead Sea

Question 3.
Sri Lanka, India, Norway, Peru
Answer:
Sri Lanka

Question 4.
Southern Ocean, Indian Ocean, Pacific Ocean, Bay of Bengal
Answer:
Bay of Bengal

Question 5.
Natural gas, salt, gold, manganese
Answer:
Natural gas

B. Write the answers:

Question 1.
Which items does man get from the oceans?
Answer:
Salt, fish, shells and other products, minerals like iron, lead, cobalt, sodium, manganese, chromium, zinc, mineral oil and natural gas are the items man gets from oceans.

Question 2.
Why It is economic to carry out transport by water ways.
Answer:

• Waterways is a cost-effective, fuel efficient and relatively more environment friendly means of transportation.
• Large scale transport of goods can be carried out with the help of ships, trawlers, boats, etc. at a low cost.
• So it is economic to carry out transport by waterway.

Question 3.
Why There is a difference in the climate of regions close to the oceans and regions far away from the oceans.
Answer:
(i) The oceans influence the climatic condition of a place. Coastal areas are cooler and wetter than regions away from the ocean.

(ii) There is a difference in the maximum and minimum temperature with the difference being less in coastal region (nearness to the sea) while it is more in the region far away from the sea (continentality).

(iii) The temperature in coastal areas remains equable due to the mixing of vapour released through evaporation of water from these water bodies into air. This vapour absorbs and stores the heat released from the land.

Question 4.
Which continents are located along the coast of the Pacific Ocean?
Answer:
Asia, Australia, North America and South America are the continents located along the coast of the Pacific Ocean.

Activity:

Colour the different oceans on an outline map of the world and prepare an index for the map. (See inside front cover, figure B.)

Project:

Group work: Make five groups. Each group should collect some information and pictures of one ocean. With the help of the information collected, each group should make a poster and make presentation.

Class 6 Geography Chapter 6 Importance of Oceans InText Questions and Answers

Think a little!

Question 1.
Where does the water flowing through the rivers go in the end?
Answer:
The water flowing through the rivers goes into the oceans in the end.

Question 2.
Are there volcanic eruptions in the seas?
Answer:
Yes, volcanic eruptions take place in the seas.

Question 3.
What would have happened if man had not discovered sea routes?
Answer:

• If there were no sea routes, we would lose out on the most economic option of transportation.
• Large scale transport of goods would become inconvenient.
• International trade too would suffer.

Use your brain power!

Question 1.
Where did all this water on the earth come from?
Answer:
While some scientists believe that water was created due to the impact of comets there are others who believe that Earth’s waters have existed since the birth of planet earth.

Find out:

Question 1.
Collect information about how a natural pearl is formed.
Answer:

• Natural pearls form when an irritant- usually a parasite and not the proverbial grain of sand – works its way into an oyster, mussel, or clam.
• As a defense mechanism, a fluid is used to coat the irritant.
• Layer upon layer of this coating called ‘nacre’ is deposited until a pearl is formed.

Question 2.
Which oceanic organism develops in it?
Answer:
The oceanic organism oyster develops in it.

Question 3.
In which sea is it found in India?
Answer:
The Arabian Sea.

What will you do?

Question 1.
Different marine animals like the blue whale, turtle, starfish, etc. appear before you in your dream and complain to you. They say, “You humans are not allowing us to live properly. You throw the waste and chemicals that you do not want into our house. The youngsters in our house are falling ill due to this. Some are getting killed. You must think about this situation and remove the pollution from the seas.” Now tell what you will do.
Answer:
“Environmental problems begin with people as the cause and end with people as the victims.” Different ways to remove pollution from sea are:

• Creating awareness amongst people.
• Organising a clean-up operation.
• Insisting that government take steps to prevent marine pollution caused due to waste disposal.
• Following the principle of recycling waste and proper treatment of sewage before its disposal into water bodies.
• Generating a sense of responsibility amongst the citizens.

Can you do it?

Question 1.
Sameer and Sania are playing a game of showing the waterways on a map of the world. Their routes are going in opposite directions. One of the following the eastern route while the other is making a route that takes to the west.

From Mumbai port some goods are to be taken to London in UK. On a map of the world, show at least two such routes with a pencil.
Write down the names of the ports of different nations that fall on the route followed by each.

Ports on the route followed by Sameer:

Answer:

• JNPT – India
• Nish tun – Yemen
• Salal – Oman
• Port of Berbera – Somalia
• Port of A1 Qusayr – Egypt
• Port of Said – Egypt Suez
• port – Egypt
• Port of Tenes – Algeria
• Port of Tunis – Tunisia
• Port of Bone facia – France
• Port of Aguilas – Spain
• Port of Adra – Spain
• Port of Gibraltar – Gibraltar
• Port of Sines – Portugal
• Swange Pier – UK
• Whitstable harbour – UK
• Purfleet Thames Terminal – UK
• Port of London – UK

Ports on the route followed by Sania:

• Port of Mergui – Myanmar
• Port of Ramong – Thailand
• Port of Krueng Raya – Indonesia, etc.

Question 2.
Which of the routes you feel is shorter? That of Sameer’s or Sania’s?
Answer:
Sameer’s route is shorter.

Question 3.
Which oceans does one have to pass through if one follows Sameer’s route or Sania’s route?
Answer:
If one follows Sameer’s route one has to pass through the Indian Ocean and North Atlantic Ocean. If Sania’s route is taken she has to pass through the Pacific and North Atlantic Ocean.

Question 4.
What are Panama and Suez? For what purpose were they constructed?
Answer:

• Panama and Suez are the canals in the sea built for commercial purpose.
• It helped in saving time, money and energy and gave a fillip to international trade due to the shorter distance and easy accessibility.

Question 5.
Have they been used in Sameer’s and Sania’s routes?
Answer:
Yes, Suez Canal is used in Sameer’s route while Panama Canal is used in Sania’s route.

Class 6 Geography Chapter 6 Importance of Oceans Additional Important Questions and Answers

Fill the blanks choosing the correct alternatives from the brackets:

Question 1.
The ______ includes all the water bodies like oceans, seas, rivers and their tributaries, lakes, reservoirs and also ground water that exist on the earth.
(lithosphere, atmosphere, hydrosphere)
Answer:
hydrosphere

Question 2.
Total global water 97.7% is contained in ______ (lakes, oceans, seas)
Answer:
oceans

Question 3.
The ocean with an area 166,240,977 sq. km is the _______ ocean. (Indian, Atlantic, Pacific)
Answer:
Pacific

Question 4.
All rivers flowing from mountains or hilly areas finally meet in the ________.(lakes, seas, oceans)
Answer:
oceans

Question 5.
Salinity is expressed in terms of ______.(mils, ml, gms)
Answer:
mils

Question 6.
The average salinity of oceanic water is _______.(80%, 332%, 35%)
Answer:
35%

Question 7.
The salinity of the Dead Sea is _____.(332 %, 35%, 60%)
Answer:
332 %

Question 8.
About ________ of the surface of the earth is occupied by water. (90%, 95%, 70.8%)
Answer:
70.8%

Question 9.
Salt as a substance is obtained by constructing ______. (sea bed, salt pan, river bunds)
Answer:
salt pan

Question 10.
________ is conducted on a much higher scale as compared to the other modes of transport. (Water transport, Air transport, Road transport)
Answer:
Water transport

Question 11.
Pollution of _________ water is caused due to oil spills. (river, lake, oceanic)
Answer:
oceanic

Question 12.
Winds blowing due to pressure difference in the belts is called ______. (planetary winds, oceanic winds, minerals)
Answer:
planetary winds

Match the pairs correctly:

Question 1.

Oceans	The area in sq. km
(1) Pacific	(a) 20,327,000
(2) Atlantic	(b) 73,426,163
(3) Indian	(c) 166,240,977
(4) Southern	(d) 13,224,479
(5) the Arctic	(e) 86,557,402

Answer:
1 – c
2 – e
3 – b
4 – a
5 – d

Find the odd man out:

Question 1.
Pearls, corals, diamonds, medicinal plants
Answer:
diamonds

Question 2.
Spain, Norway, Japan, India
Answer:
India

Question 3.
Blue whale, sea turtles, seerfish, dolphins
Answer:
seerfish

Name the following:

Question 1.
Water bodies which are a part of the . hydrosphere.
Answer:
Oceans, seas, rivers and their tributaries, lakes, reservoirs, ground water.
Question 2.
Percentage of global waters contained in oceans.
Answer:
97.7%

Question 3.
Two aquatic animals found in the ocean.
Answer:

• Microscopic planktons
• Huge whales

Question 5.
Places where volcanic eruptions occur.
Answer:

• Land
• Ocean

Question 6.
Two minerals obtained from the sea.
Answer:

• Phosphates
• Sulphates

Question 7.
Two uses of marine animals.
Answer:

• Production of fertilisers
• Production of pharmaceuticals

Question 8.
Two countries with coastline which largely depends on the sea for their livelihood.
Answer:

• Seychelles
• Mauritius

Question 9.
The controller of global temperature and source of rains.
Answer:
Oceans.

Question 10.
The beginning and end of the water cycle takes place here.
Answer:
Oceans.

Question 11.
Two minerals obtained from the ocean floor.
Answer:

• Cobalt
• Sodium

Question 12.
Precious items obtained from the seas.
Answer:

• Pearls
• Corals

Question 13.
Mode of transport used for large scale transportation of goods.
Answer:

• Ships
• Trawlers

Question 14.
Two actions by man which has lead to large scale pollution in oceanic waters.
Answer:

• Oil spills
• Exploitative fishing

Answer the following in one sentence each:

Question 1.
What happens when aquatic animals die?
Answer:
When aquatic animals die, their remains accumulate in the oceans.

Question 2.
What enters the ocean with the rain water?
Answer:
Sediments from eroded lands, trees and bushes flowing with water, dead remains, etc. enter the ocean with the river water.

Question 3.
What happens when the dead remains in the ocean decompose?
Answer:
When the dead remains in the oceans decompose it releases various minerals and salts in the ocean water.

Question 4.
Where do we find maximum salinity?
Answer:
The Dead Sea is known to have the maximum salinity of 332%.

Question 5.
How is salt obtained?
Answer:
Salt as a substance is obtained by constructing salt pans in the coastal areas.

Question 6.
Which is one of the ancient occupations of human beings and what is the major purpose of his activity?
Answer:
Fishing is one of the ancient occupation and the major purpose of this activity is to obtain food.

Question 7.
How does the earth get rainfall?
Answer:
The oceans have a vast expanse, therefore huge amounts of vapour get created and this process goes on continuously and from this vapour the earth gets rainfall.

Question 8.
How is pollution caused in oceanic water?
Answer:
In order to fulfill his requirements, man undertakes many activities that lead to the production of huge amounts of different types of waste materials which cause pollution.

Question 9.
Write anyone cause of pollution of oceanic waters.
Answer:
Cutting of mangroves forests in coastal areas is one of the main cause of pollution in oceanic waters.

Question 10.
How does oceanic pollution affect the aquatic animals?
Answer:
Due to oceanic pollution many aquatic animals are under the threat of being extinct. For example, the blue whale, some types of sea turtles, dolphins, etc.

Question 11.
Which items does man get from the oceans?
Answer:
Salt, fish, shells and other products, minerals like iron, lead, cobalt, sodium, manganese, chromium, zinc, mineral oil and natural gas are the items man gets from oceans.

Question 12.
Which continents are located along the coast of the Pacific Ocean?
Answer:
Asia, Australia, North America and South America are the continents located along the coast of the Pacific Ocean.

Give geographical reasons for the following statements:

Question 1.
The ocean water is saltier than drinking water.
Answer:

(i) In drinking water, the proportion of salts is quite low. Water from oceans and seas has a greater amount of salt. Hence it tastes salty.

(ii) Volcanic eruptions leads to increase in the level of salts and minerals in ocean water.

(iii) Volcanic eruptions takes place in the oceans. During volcanic eruptions different minerals, ashes, salts and gases are added to the water. This increases the level of salts and minerals in ocean water.

(iv) Due to continuous evaporation of oceanic water, the proportion of salt increase.

Question 2.
The temperature in coastal areas remains equable.
Answer:

(i) In regions close to the oceans, seas or large reservoirs, there is not much of a difference in the temperature throughout the day.

(ii) The main reason for this is the mixing of vapour released through evaporation of water from these water bodies into air.

(iii) This vapour in the air absorbs and stores the heat released from the land.

(iv) Hence, the temperature in coastal regions remain equable.

Question 3.
It is economic to carry out transport by water ways.
Answer:

• Waterways is a cost-effective, fuel efficient and relatively more environment friendly means of transportation.
• Large scale transport of goods can be carried out with the help of ships, trawlers, boats, etc. at a low cost.
• So it is economic to carry out transport by waterway.

Question 4.
There is a difference in the climate of regions close to the oceans and regions far away from the oceans.
Answer:
(i) The oceans influence the climatic condition of a place. Coastal areas are cooler and wetter than regions away from the ocean.

(ii) There is a difference in the maximum and minimum temperature with the difference being less in coastal region (nearness to the sea) while it is more in the region far away from the sea (continentality).

(iii) The temperature in coastal areas remains equable due to the mixing of vapour released through evaporation of water from these water bodies into air. This vapour absorbs and stores the heat released from the land.

Question 5.
Oceans act as the controller of global temperature.
Answer:

(i) Winds move the oceanic water in the form of currents.

(ii) Ocean currents move from the equatorial region to polar regions and from polar regions to the equatorial region.

(iii) This leads to the redistribution of heat on the earth.

(iv) The cold currents moving towards the equatorial region making the temperature of coastal areas in that zone milder whereas the warm currents coming in the colder region cause the temperature in coastal areas to rise. Hence, the oceans act as the controller of global temperature.

Answer the following questions in brief:

Question 1.
What are planetary winds?
Answer:

• Equatorial regions receives perpendicular sunrays.
• As a result these areas get more heat whereas the polar regions receive highly slant rays.
• This differential heating creates imbalance in the temperature of air in different parts leading to formation of belts of high and low pressure on earth.
• Winds blow1 due to the pressure differences in these belts. These winds are called Planetary Winds.

Question 2.
Write in brief about oceanic transport.
Answer:

• Oceans have provided us the most economic option of transportation.
• Large scale transportation of goods is carried out with the help of ships, trawlers, boats, etc.
• International trade is carried out on a large scale using waterways.
• Countries like Spain, Norway, Japan have a good coastline due to which goods are transported by ocean routes, making these countries important.

Question 3.
How do ocean currents aid water transport?
Answer:

• Ocean currents are quite important in water transport.
• As far as possible water transport is carried out along ocean currents.
• They accelerate the speed of the ships and also save fuel to a considerable extent.

Question 4.
List the causes that lead to large scale pollution of oceanic water.
Answer:
The causes that lead to large scale pollution of oceanic water are:

• Oil spills.
• Releasing the waste produced in the coastal cities into the seas.
• Materials thrown out from ships.
• Exploitative fishing.
• Cutting of mangrove forests in coastal areas.
• Disasters caused by the water mines.
• Sewage released by industries and cities.
• Excavation carried out in the seas.

Do it yourself!

Question 1.
Calculate the difference between the mean maximum and minimum temperature and write in the last column

Place	Country	Mean Max. Temp. °C	Mean Min. Temp. °C	Range of Temperature
Beijing	China	18.4	08.4	10
Istanbul	Turkey	18.0	10.0	08		_______
Madrid	Spain	19.0	09.0	10
New York66	United States	16.3	08.3	08		________
Denver	United States	16.2	02.2	14
Kabul	Afghanistan	14.7	05.2	09.5		________
Baghdad	Iraq	30.4	14.7	15.7

Question 2.
Highlight the rows for the places having a range of temperatures over 10°C with red colour, other rows in blue colour (Refer the above table)
Question 3.
Find the locations of these places from an atlas. (Students activity)
Question 4.
Which places are closer to the oceans? Tell whether the range of temperature at these
places is l ess or more?
Answer:
Istanbul and New York are closer to the oceans. These places which are closer to the oceans have lesser range of temperature.

Question 5.
What might be the main reason leading to differences in the temperature range in different places?
Answer:
The main reason leading to differences in temperature range in different places is because of the location of the place on the planet earth. Other factors like latitude, altitude, atmosphere, ocean currents, planetary winds etc. too have their impact.

Question 6.
In which thermal zone are all these places located?
Answer:
All these places are located in the temperate thermal zone.

Question 7.
Which places are fai away from the oceans?
Do these places have a greater or smaller temperature range?
Answer:
Istanbul, Denver, Kabul and Baghdad are far away from the ocean as these places have a greater temperature range.

Question 8.
Mention the places having the smallest and greatest temperature ranges.
Answer:
Istanbul and New York have the smallest temperature range while Baghdad has the greatest temperature range.

Question 9.
Draw a graph for the above data. Use a proper colour scheme.
Answer: