Class 9 Science: Solutions of Sample Practice Question Paper- 6 PDF Download

 Page 1


  
 
CBSE IX | SCIENCE 
Sample Paper – 6 Solution 
 
    
CBSE  
Class IX Science 
Sample Paper – 6 Solution  
 
  Section A 
 
1. Processes involved in soil formation: 
(a) Weathering  
(b) Paedogenesis 
 
2. Initiatives taken to increase the water availability for agriculture: 
(a) Rainwater harvesting 
(b) Watershed management 
 
Section B 
 
3. Properties of suspensions: 
? They are heterogeneous mixtures. 
? Their particles can be easily seen by the naked eye. 
? They are unstable since their particles settle after some time when left 
undisturbed.  
       Examples: Oil and water, sand and water 
OR 
Chlorine gas is added to water to purify it. It kills the germs present in water. 
It is called a disinfectant as it is used to sterilise water. After this treatment, water 
becomes safe for drinking. 
 
4. When the cells of onion peel and RBCs are kept separately in a hypotonic solution, 
RBCs will burst because there is no mechanism to resist the entry of water inside 
the cells. Cells of the onion peel will not burst. Entry of water due to endosmosis will 
cause some initial swelling in the onion peel cells. However, the cell wall acts as a 
mechanical barrier and restricts the further entry of water inside the cell. As a 
result, the onion peel cells do not burst. 
 
5. Weight of box on the Earth = 200 N 
Thus, its mass on the Earth is given by 
 W = m × g 
?m = 
W
g
 = 
200
10
 = 20 kg 
As the mass of the box is 20 kg on the Earth, its mass will remain the same on the 
Moon. 
Hence, the mass of the object on the Moon is also 20 kg. 
Page 2


  
 
CBSE IX | SCIENCE 
Sample Paper – 6 Solution 
 
    
CBSE  
Class IX Science 
Sample Paper – 6 Solution  
 
  Section A 
 
1. Processes involved in soil formation: 
(a) Weathering  
(b) Paedogenesis 
 
2. Initiatives taken to increase the water availability for agriculture: 
(a) Rainwater harvesting 
(b) Watershed management 
 
Section B 
 
3. Properties of suspensions: 
? They are heterogeneous mixtures. 
? Their particles can be easily seen by the naked eye. 
? They are unstable since their particles settle after some time when left 
undisturbed.  
       Examples: Oil and water, sand and water 
OR 
Chlorine gas is added to water to purify it. It kills the germs present in water. 
It is called a disinfectant as it is used to sterilise water. After this treatment, water 
becomes safe for drinking. 
 
4. When the cells of onion peel and RBCs are kept separately in a hypotonic solution, 
RBCs will burst because there is no mechanism to resist the entry of water inside 
the cells. Cells of the onion peel will not burst. Entry of water due to endosmosis will 
cause some initial swelling in the onion peel cells. However, the cell wall acts as a 
mechanical barrier and restricts the further entry of water inside the cell. As a 
result, the onion peel cells do not burst. 
 
5. Weight of box on the Earth = 200 N 
Thus, its mass on the Earth is given by 
 W = m × g 
?m = 
W
g
 = 
200
10
 = 20 kg 
As the mass of the box is 20 kg on the Earth, its mass will remain the same on the 
Moon. 
Hence, the mass of the object on the Moon is also 20 kg. 
  
 
CBSE IX | SCIENCE 
Sample Paper – 6 Solution 
 
    
Section C 
 
6.  
(a) Speed is the distance travelled by a body per unit time. Its SI unit is metre per 
second (m/s). 
Distance m
Speed
Time s
??
 
(b)  
(i) Velocity of the body is the distance travelled by it per unit time in a given 
direction. 
(ii) The body exhibits non-uniform acceleration if its velocity increases by equal 
intervals of time.  
 
(c) Average velocity (v ¯) = initial velocity (u) + final velocity(v)_ 
                                                                                   2 
 
7. The given organism is an octopus. It belongs to Phylum Mollusca. 
Characteristics of Phylum Mollusca: (Any two) 
(a) Bilateral symmetry 
(b) Open circulatory system 
(c) Coelomic cavity is reduced 
(d) Metanephridia or kidney-like organ for excretion 
 
8.  
(a) Passengers in the bus will move in a backward direction. When the bus is at rest, 
the passengers in the bus are also in the rest position. When the bus starts 
suddenly, the speed of the bus changes. The passengers’ lower portion of the 
body is in contact with the bus, but the upper portion is still at rest for that 
moment. Hence, the passengers get a sudden jerk and move in the backward 
direction.   
 
(b) Yes, the boy is experiencing accelerated motion. As he is moving in a circular 
track, his direction keeps on changing continuously. Thus, he is said to be 
moving in accelerated motion. 
  
Page 3


  
 
CBSE IX | SCIENCE 
Sample Paper – 6 Solution 
 
    
CBSE  
Class IX Science 
Sample Paper – 6 Solution  
 
  Section A 
 
1. Processes involved in soil formation: 
(a) Weathering  
(b) Paedogenesis 
 
2. Initiatives taken to increase the water availability for agriculture: 
(a) Rainwater harvesting 
(b) Watershed management 
 
Section B 
 
3. Properties of suspensions: 
? They are heterogeneous mixtures. 
? Their particles can be easily seen by the naked eye. 
? They are unstable since their particles settle after some time when left 
undisturbed.  
       Examples: Oil and water, sand and water 
OR 
Chlorine gas is added to water to purify it. It kills the germs present in water. 
It is called a disinfectant as it is used to sterilise water. After this treatment, water 
becomes safe for drinking. 
 
4. When the cells of onion peel and RBCs are kept separately in a hypotonic solution, 
RBCs will burst because there is no mechanism to resist the entry of water inside 
the cells. Cells of the onion peel will not burst. Entry of water due to endosmosis will 
cause some initial swelling in the onion peel cells. However, the cell wall acts as a 
mechanical barrier and restricts the further entry of water inside the cell. As a 
result, the onion peel cells do not burst. 
 
5. Weight of box on the Earth = 200 N 
Thus, its mass on the Earth is given by 
 W = m × g 
?m = 
W
g
 = 
200
10
 = 20 kg 
As the mass of the box is 20 kg on the Earth, its mass will remain the same on the 
Moon. 
Hence, the mass of the object on the Moon is also 20 kg. 
  
 
CBSE IX | SCIENCE 
Sample Paper – 6 Solution 
 
    
Section C 
 
6.  
(a) Speed is the distance travelled by a body per unit time. Its SI unit is metre per 
second (m/s). 
Distance m
Speed
Time s
??
 
(b)  
(i) Velocity of the body is the distance travelled by it per unit time in a given 
direction. 
(ii) The body exhibits non-uniform acceleration if its velocity increases by equal 
intervals of time.  
 
(c) Average velocity (v ¯) = initial velocity (u) + final velocity(v)_ 
                                                                                   2 
 
7. The given organism is an octopus. It belongs to Phylum Mollusca. 
Characteristics of Phylum Mollusca: (Any two) 
(a) Bilateral symmetry 
(b) Open circulatory system 
(c) Coelomic cavity is reduced 
(d) Metanephridia or kidney-like organ for excretion 
 
8.  
(a) Passengers in the bus will move in a backward direction. When the bus is at rest, 
the passengers in the bus are also in the rest position. When the bus starts 
suddenly, the speed of the bus changes. The passengers’ lower portion of the 
body is in contact with the bus, but the upper portion is still at rest for that 
moment. Hence, the passengers get a sudden jerk and move in the backward 
direction.   
 
(b) Yes, the boy is experiencing accelerated motion. As he is moving in a circular 
track, his direction keeps on changing continuously. Thus, he is said to be 
moving in accelerated motion. 
  
  
 
CBSE IX | SCIENCE 
Sample Paper – 6 Solution 
 
    
9. Given: 
     Molecular mass of Cr2S3 = (2 × 52) + (3 × 32) 
    = 200 g 
      Now, 200 g of Cr2S3 contains = 104 g of Cr 
So, 85 g of Cr2S3 will contain=104 × 85  
                                                                     200 
                                                     = 44.2 g of Cr 
 Hence, the number of moles of Cr =   44.2 
                                                                52 
                                                               = 0.85 moles 
 
OR 
 
? ?
? ?
? ?
   
a
  Formula unit mass of CaCO   u   u   x  u                                    
            u
b 
Molar mass of CO     x  g mole                   
                      g mole
?
? ? ?
?
??
?
3
1
2
40 12 3 16
100
12 2 16
44
? ?
   
   
  mass of  moles of CO   mole x  g mole                      
                      g
c
Given mass of Helium 
    Number of He atoms    
Mass of  atom of Helium
                   
 
?
?
?
?
?
?
1
1
2
10 10 44
440
1
100
4
                  ? 25
  
 
10.  
(a) Yellow pale eyes, general weakness, nausea and vomiting are symptoms of 
jaundice. 
(b) Jaundice is a disease caused by viruses. 
(c) Helping nature, friendly concern and general awareness are some values 
depicted by Rahul. 
 
 
  
Page 4


  
 
CBSE IX | SCIENCE 
Sample Paper – 6 Solution 
 
    
CBSE  
Class IX Science 
Sample Paper – 6 Solution  
 
  Section A 
 
1. Processes involved in soil formation: 
(a) Weathering  
(b) Paedogenesis 
 
2. Initiatives taken to increase the water availability for agriculture: 
(a) Rainwater harvesting 
(b) Watershed management 
 
Section B 
 
3. Properties of suspensions: 
? They are heterogeneous mixtures. 
? Their particles can be easily seen by the naked eye. 
? They are unstable since their particles settle after some time when left 
undisturbed.  
       Examples: Oil and water, sand and water 
OR 
Chlorine gas is added to water to purify it. It kills the germs present in water. 
It is called a disinfectant as it is used to sterilise water. After this treatment, water 
becomes safe for drinking. 
 
4. When the cells of onion peel and RBCs are kept separately in a hypotonic solution, 
RBCs will burst because there is no mechanism to resist the entry of water inside 
the cells. Cells of the onion peel will not burst. Entry of water due to endosmosis will 
cause some initial swelling in the onion peel cells. However, the cell wall acts as a 
mechanical barrier and restricts the further entry of water inside the cell. As a 
result, the onion peel cells do not burst. 
 
5. Weight of box on the Earth = 200 N 
Thus, its mass on the Earth is given by 
 W = m × g 
?m = 
W
g
 = 
200
10
 = 20 kg 
As the mass of the box is 20 kg on the Earth, its mass will remain the same on the 
Moon. 
Hence, the mass of the object on the Moon is also 20 kg. 
  
 
CBSE IX | SCIENCE 
Sample Paper – 6 Solution 
 
    
Section C 
 
6.  
(a) Speed is the distance travelled by a body per unit time. Its SI unit is metre per 
second (m/s). 
Distance m
Speed
Time s
??
 
(b)  
(i) Velocity of the body is the distance travelled by it per unit time in a given 
direction. 
(ii) The body exhibits non-uniform acceleration if its velocity increases by equal 
intervals of time.  
 
(c) Average velocity (v ¯) = initial velocity (u) + final velocity(v)_ 
                                                                                   2 
 
7. The given organism is an octopus. It belongs to Phylum Mollusca. 
Characteristics of Phylum Mollusca: (Any two) 
(a) Bilateral symmetry 
(b) Open circulatory system 
(c) Coelomic cavity is reduced 
(d) Metanephridia or kidney-like organ for excretion 
 
8.  
(a) Passengers in the bus will move in a backward direction. When the bus is at rest, 
the passengers in the bus are also in the rest position. When the bus starts 
suddenly, the speed of the bus changes. The passengers’ lower portion of the 
body is in contact with the bus, but the upper portion is still at rest for that 
moment. Hence, the passengers get a sudden jerk and move in the backward 
direction.   
 
(b) Yes, the boy is experiencing accelerated motion. As he is moving in a circular 
track, his direction keeps on changing continuously. Thus, he is said to be 
moving in accelerated motion. 
  
  
 
CBSE IX | SCIENCE 
Sample Paper – 6 Solution 
 
    
9. Given: 
     Molecular mass of Cr2S3 = (2 × 52) + (3 × 32) 
    = 200 g 
      Now, 200 g of Cr2S3 contains = 104 g of Cr 
So, 85 g of Cr2S3 will contain=104 × 85  
                                                                     200 
                                                     = 44.2 g of Cr 
 Hence, the number of moles of Cr =   44.2 
                                                                52 
                                                               = 0.85 moles 
 
OR 
 
? ?
? ?
? ?
   
a
  Formula unit mass of CaCO   u   u   x  u                                    
            u
b 
Molar mass of CO     x  g mole                   
                      g mole
?
? ? ?
?
??
?
3
1
2
40 12 3 16
100
12 2 16
44
? ?
   
   
  mass of  moles of CO   mole x  g mole                      
                      g
c
Given mass of Helium 
    Number of He atoms    
Mass of  atom of Helium
                   
 
?
?
?
?
?
?
1
1
2
10 10 44
440
1
100
4
                  ? 25
  
 
10.  
(a) Yellow pale eyes, general weakness, nausea and vomiting are symptoms of 
jaundice. 
(b) Jaundice is a disease caused by viruses. 
(c) Helping nature, friendly concern and general awareness are some values 
depicted by Rahul. 
 
 
  
  
 
CBSE IX | SCIENCE 
Sample Paper – 6 Solution 
 
    
11. Mass of the bullet, m1 = 15 g 
??
1
15
m 0.015 kg
1000
 
Velocity of the bullet, v1 = 500 m/s 
Mass of the gun, m2 = 5 kg 
Recoil velocity of the gun, vR = ? 
Recoil velocity can be obtained by using the relation: 
Mass of bullet × velocity of bullet = mass of gun × recoil velocity 
??
?
? ? ?
??
1 1 2 R
11
R
2
R
m v m v
mv 0.015 500
v
m5
v 1.5 m/s
 
OR 
 
(a) Graph (C) represents the motion of a car on a crowded street. As the street is 
crowded, the driver drives the car with different speeds in equal intervals of 
time. This graph represents non-uniform acceleration. 
(b) Graph (D) represents the motion of a ball falling from a height. The ball falling 
from a height covers unequal distances in equal intervals of time. This graph 
represents non-uniform motion of the ball. 
(c) Graph (A) is incorrectly represented. This graph shows that with increasing 
speed, time goes on decreasing which is not possible. Hence, the graph is 
incorrectly represented. 
 
12.  
(a) Pesticides when washed away into the soil or water bodies get absorbed by 
plants. Because they are non-biodegradable, they remain in the soil, water and 
bodies of plants. When plants are consumed as food by man or other animals, 
these chemicals enter the food chain and harm human beings and other animals. 
(b) As far as possible, farmers should avoid the use of pesticides or they can use 
pesticides in limited amounts. Instead, they should use biological methods to 
control pests as they do not cause any environmental pollution. It is our 
responsibility to keep our environment pollution-free. 
OR 
 
  
Page 5


  
 
CBSE IX | SCIENCE 
Sample Paper – 6 Solution 
 
    
CBSE  
Class IX Science 
Sample Paper – 6 Solution  
 
  Section A 
 
1. Processes involved in soil formation: 
(a) Weathering  
(b) Paedogenesis 
 
2. Initiatives taken to increase the water availability for agriculture: 
(a) Rainwater harvesting 
(b) Watershed management 
 
Section B 
 
3. Properties of suspensions: 
? They are heterogeneous mixtures. 
? Their particles can be easily seen by the naked eye. 
? They are unstable since their particles settle after some time when left 
undisturbed.  
       Examples: Oil and water, sand and water 
OR 
Chlorine gas is added to water to purify it. It kills the germs present in water. 
It is called a disinfectant as it is used to sterilise water. After this treatment, water 
becomes safe for drinking. 
 
4. When the cells of onion peel and RBCs are kept separately in a hypotonic solution, 
RBCs will burst because there is no mechanism to resist the entry of water inside 
the cells. Cells of the onion peel will not burst. Entry of water due to endosmosis will 
cause some initial swelling in the onion peel cells. However, the cell wall acts as a 
mechanical barrier and restricts the further entry of water inside the cell. As a 
result, the onion peel cells do not burst. 
 
5. Weight of box on the Earth = 200 N 
Thus, its mass on the Earth is given by 
 W = m × g 
?m = 
W
g
 = 
200
10
 = 20 kg 
As the mass of the box is 20 kg on the Earth, its mass will remain the same on the 
Moon. 
Hence, the mass of the object on the Moon is also 20 kg. 
  
 
CBSE IX | SCIENCE 
Sample Paper – 6 Solution 
 
    
Section C 
 
6.  
(a) Speed is the distance travelled by a body per unit time. Its SI unit is metre per 
second (m/s). 
Distance m
Speed
Time s
??
 
(b)  
(i) Velocity of the body is the distance travelled by it per unit time in a given 
direction. 
(ii) The body exhibits non-uniform acceleration if its velocity increases by equal 
intervals of time.  
 
(c) Average velocity (v ¯) = initial velocity (u) + final velocity(v)_ 
                                                                                   2 
 
7. The given organism is an octopus. It belongs to Phylum Mollusca. 
Characteristics of Phylum Mollusca: (Any two) 
(a) Bilateral symmetry 
(b) Open circulatory system 
(c) Coelomic cavity is reduced 
(d) Metanephridia or kidney-like organ for excretion 
 
8.  
(a) Passengers in the bus will move in a backward direction. When the bus is at rest, 
the passengers in the bus are also in the rest position. When the bus starts 
suddenly, the speed of the bus changes. The passengers’ lower portion of the 
body is in contact with the bus, but the upper portion is still at rest for that 
moment. Hence, the passengers get a sudden jerk and move in the backward 
direction.   
 
(b) Yes, the boy is experiencing accelerated motion. As he is moving in a circular 
track, his direction keeps on changing continuously. Thus, he is said to be 
moving in accelerated motion. 
  
  
 
CBSE IX | SCIENCE 
Sample Paper – 6 Solution 
 
    
9. Given: 
     Molecular mass of Cr2S3 = (2 × 52) + (3 × 32) 
    = 200 g 
      Now, 200 g of Cr2S3 contains = 104 g of Cr 
So, 85 g of Cr2S3 will contain=104 × 85  
                                                                     200 
                                                     = 44.2 g of Cr 
 Hence, the number of moles of Cr =   44.2 
                                                                52 
                                                               = 0.85 moles 
 
OR 
 
? ?
? ?
? ?
   
a
  Formula unit mass of CaCO   u   u   x  u                                    
            u
b 
Molar mass of CO     x  g mole                   
                      g mole
?
? ? ?
?
??
?
3
1
2
40 12 3 16
100
12 2 16
44
? ?
   
   
  mass of  moles of CO   mole x  g mole                      
                      g
c
Given mass of Helium 
    Number of He atoms    
Mass of  atom of Helium
                   
 
?
?
?
?
?
?
1
1
2
10 10 44
440
1
100
4
                  ? 25
  
 
10.  
(a) Yellow pale eyes, general weakness, nausea and vomiting are symptoms of 
jaundice. 
(b) Jaundice is a disease caused by viruses. 
(c) Helping nature, friendly concern and general awareness are some values 
depicted by Rahul. 
 
 
  
  
 
CBSE IX | SCIENCE 
Sample Paper – 6 Solution 
 
    
11. Mass of the bullet, m1 = 15 g 
??
1
15
m 0.015 kg
1000
 
Velocity of the bullet, v1 = 500 m/s 
Mass of the gun, m2 = 5 kg 
Recoil velocity of the gun, vR = ? 
Recoil velocity can be obtained by using the relation: 
Mass of bullet × velocity of bullet = mass of gun × recoil velocity 
??
?
? ? ?
??
1 1 2 R
11
R
2
R
m v m v
mv 0.015 500
v
m5
v 1.5 m/s
 
OR 
 
(a) Graph (C) represents the motion of a car on a crowded street. As the street is 
crowded, the driver drives the car with different speeds in equal intervals of 
time. This graph represents non-uniform acceleration. 
(b) Graph (D) represents the motion of a ball falling from a height. The ball falling 
from a height covers unequal distances in equal intervals of time. This graph 
represents non-uniform motion of the ball. 
(c) Graph (A) is incorrectly represented. This graph shows that with increasing 
speed, time goes on decreasing which is not possible. Hence, the graph is 
incorrectly represented. 
 
12.  
(a) Pesticides when washed away into the soil or water bodies get absorbed by 
plants. Because they are non-biodegradable, they remain in the soil, water and 
bodies of plants. When plants are consumed as food by man or other animals, 
these chemicals enter the food chain and harm human beings and other animals. 
(b) As far as possible, farmers should avoid the use of pesticides or they can use 
pesticides in limited amounts. Instead, they should use biological methods to 
control pests as they do not cause any environmental pollution. It is our 
responsibility to keep our environment pollution-free. 
OR 
 
  
  
 
CBSE IX | SCIENCE 
Sample Paper – 6 Solution 
 
    
Management practices followed in a livestock firm: (any six points) 
(a) Provision of shelter facilities under well-ventilated roofed sheds 
(b) Proper cleaning of shelters 
(c) Regular brushing of animals to remove dirt and loose hair 
(d) Provision of nutritious food which includes a balanced ratio of fibre, roughage 
and concentrates 
(e) Provision of special food during the lactation period  
(f) Check against external parasites and skin check against internal parasites such 
as norms and flukes 
(g) Vaccination against viral and bacterial diseases 
 
13.  
(i) The large or extranuclear part of the atoms contains electrons which have 
negligible mass. Heavier particles like protons and neutrons are contained in the 
nucleus. So, only the nucleus is taken into account when calculating the mass of an 
atom. 
(ii) Atoms combine with other atoms to achieve the electronic configuration of the 
nearest noble gas to become more stable. 
 
14. It is possible to differentiate between squamous, cuboidal and columnar epithelia 
under the microscope just by looking at the cells. The shape of the cells in these 
epithelia helps us to identify the type of epithelium. If the slide shows flat and 
irregular cells, the epithelium is squamous; if the cells are cube-like, the epithelium 
is cuboidal, whereas if the cells are tall and pillar-like, the epithelium is columnar. 
 
15. Possible reasons to justify this statement: 
1. Forces of attraction between particles are maximum in solids and minimum in 
gases. 
2. Spaces between the constituent particles and kinetic energy of the particles are 
minimum for solids and maximum for gases. 
3. Solids have fixed shape and are not compressible. The arrangement of particles is 
the most ordered for solids.