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

 Page 1


  
 
CBSE IX | SCIENCE 
Sample Paper – 9 Solution 
 
  
CBSE  
Class IX Science 
Sample Paper – 9 Solution  
 
Section A 
 
1. Leghaemoglobin is a pink-coloured protein present inside the root nodules of 
leguminous plants. 
 
2.  
Macronutrients: Nitrogen, phosphorus (any one) 
Micronutrients: Iron, manganese (any one) 
 
3. Noble gases such as helium, neon, argon and krypton are chemically unreactive and 
exist in the free state as single atoms, i.e. they have one atom each in their molecules. 
Examples: He, Ne, Ar and Kr. So, the atomicity of noble gases is 1. 
 
OR 
 
i. Ammonium sulphate: (NH4)2SO4 
ii. Magnesium carbonate: MgCO3 
 
4. Sound waves produced per second is the frequency of the sound wave. 
As 10 waves are produced per second, the frequency is 10 Hz. 
The time period of a wave is the reciprocal of the frequency. 
?
? ? ?
1
T
f
1
T 0.1 seconds
10
 
So, the time period of a sound wave is 0.1 seconds. 
 
5.  
(a) Collenchyma, a mechanical tissue, provides mechanical support and elasticity.  
(b) It provides tensile strength with flexibility to plant parts such as the stem, 
branches and leaves which allow their easy bending without breaking them. 
(c) Therefore, branches of a tree are able to move and bend freely despite high 
winds. 
  
Page 2


  
 
CBSE IX | SCIENCE 
Sample Paper – 9 Solution 
 
  
CBSE  
Class IX Science 
Sample Paper – 9 Solution  
 
Section A 
 
1. Leghaemoglobin is a pink-coloured protein present inside the root nodules of 
leguminous plants. 
 
2.  
Macronutrients: Nitrogen, phosphorus (any one) 
Micronutrients: Iron, manganese (any one) 
 
3. Noble gases such as helium, neon, argon and krypton are chemically unreactive and 
exist in the free state as single atoms, i.e. they have one atom each in their molecules. 
Examples: He, Ne, Ar and Kr. So, the atomicity of noble gases is 1. 
 
OR 
 
i. Ammonium sulphate: (NH4)2SO4 
ii. Magnesium carbonate: MgCO3 
 
4. Sound waves produced per second is the frequency of the sound wave. 
As 10 waves are produced per second, the frequency is 10 Hz. 
The time period of a wave is the reciprocal of the frequency. 
?
? ? ?
1
T
f
1
T 0.1 seconds
10
 
So, the time period of a sound wave is 0.1 seconds. 
 
5.  
(a) Collenchyma, a mechanical tissue, provides mechanical support and elasticity.  
(b) It provides tensile strength with flexibility to plant parts such as the stem, 
branches and leaves which allow their easy bending without breaking them. 
(c) Therefore, branches of a tree are able to move and bend freely despite high 
winds. 
  
  
 
CBSE IX | SCIENCE 
Sample Paper – 9 Solution 
 
  
Section C 
 
6.  
(a) Cell membrane/Plasma membrane 
(b) Hypertonic solution 
(c) Cellulose  
 
7.  
 
Hydra 
 
OR 
 
Differences between gymnosperms and angiosperms: 
Gymnosperms Angiosperms 
1. Plants bear naked seeds. 1. Plants bear seeds which develop 
inside the fruit. 
2. Endosperm cells are haploid. 2. Endosperm cells are triploid. 
3. Sporophylls aggregate to form 
cones. 
3. Sporophylls aggregate to form 
flowers. 
4. Examples: Pine, spruce, fir 4. Examples: Sunflower, oak, lily 
 
8. The mass of the ball is (m)= 400 g=
400
0.4
1000
kg ? 
 The initial velocity of the ball is 12 m/s 
i)Thus initial momentum p = m u
p= 0.4 12 4.8 kg m/s.
ii) the velocity of the ball at the highest point (v)=0
The momentum at the highest point of its fligh
?
? ? ?
t will be zero
 
Page 3


  
 
CBSE IX | SCIENCE 
Sample Paper – 9 Solution 
 
  
CBSE  
Class IX Science 
Sample Paper – 9 Solution  
 
Section A 
 
1. Leghaemoglobin is a pink-coloured protein present inside the root nodules of 
leguminous plants. 
 
2.  
Macronutrients: Nitrogen, phosphorus (any one) 
Micronutrients: Iron, manganese (any one) 
 
3. Noble gases such as helium, neon, argon and krypton are chemically unreactive and 
exist in the free state as single atoms, i.e. they have one atom each in their molecules. 
Examples: He, Ne, Ar and Kr. So, the atomicity of noble gases is 1. 
 
OR 
 
i. Ammonium sulphate: (NH4)2SO4 
ii. Magnesium carbonate: MgCO3 
 
4. Sound waves produced per second is the frequency of the sound wave. 
As 10 waves are produced per second, the frequency is 10 Hz. 
The time period of a wave is the reciprocal of the frequency. 
?
? ? ?
1
T
f
1
T 0.1 seconds
10
 
So, the time period of a sound wave is 0.1 seconds. 
 
5.  
(a) Collenchyma, a mechanical tissue, provides mechanical support and elasticity.  
(b) It provides tensile strength with flexibility to plant parts such as the stem, 
branches and leaves which allow their easy bending without breaking them. 
(c) Therefore, branches of a tree are able to move and bend freely despite high 
winds. 
  
  
 
CBSE IX | SCIENCE 
Sample Paper – 9 Solution 
 
  
Section C 
 
6.  
(a) Cell membrane/Plasma membrane 
(b) Hypertonic solution 
(c) Cellulose  
 
7.  
 
Hydra 
 
OR 
 
Differences between gymnosperms and angiosperms: 
Gymnosperms Angiosperms 
1. Plants bear naked seeds. 1. Plants bear seeds which develop 
inside the fruit. 
2. Endosperm cells are haploid. 2. Endosperm cells are triploid. 
3. Sporophylls aggregate to form 
cones. 
3. Sporophylls aggregate to form 
flowers. 
4. Examples: Pine, spruce, fir 4. Examples: Sunflower, oak, lily 
 
8. The mass of the ball is (m)= 400 g=
400
0.4
1000
kg ? 
 The initial velocity of the ball is 12 m/s 
i)Thus initial momentum p = m u
p= 0.4 12 4.8 kg m/s.
ii) the velocity of the ball at the highest point (v)=0
The momentum at the highest point of its fligh
?
? ? ?
t will be zero
 
  
 
CBSE IX | SCIENCE 
Sample Paper – 9 Solution 
 
  
OR 
 
Assuming that there is no external unbalanced force working in the horizontal 
direction. 
The momentum of the girl and the cart before the jump is equal to the momentum of 
the girl and the cart after the jump. After the jump, the cart and girl travel with the 
same velocity v. 
 
? ?
? ?
1 1 2 2 1 2
m u m u m m v
40 5 0 40 3 v
200
v 4.65 m/s
43
? ? ?
? ? ? ? ?
? ? ?
 
9. Alloys are homogeneous mixtures of metals and cannot be separated into their 
components by physical methods. But still, an alloy is considered a mixture because 
it shows the properties of its constituents and can have variable composition. 
For example, brass is a mixture of approximately 30% zinc and 70% copper. 
 
10. Factors for crop variety improvement: 
(a) Higher yield 
(b) Improved quality 
(c) Photo-sensitivity and thermo-sensitivity 
(d) Disease resistance 
(e) Pest resistance 
(f) Desirable agronomic characters 
 
11.  
(a) Although Echidna and Platypus lay eggs, they are warm blooded and feed their 
young ones with milk. Hence, they are considered mammals. 
(b) Despite a four-chambered heart, the crocodile is a cold-blooded animal. Hence, it 
is considered a reptile. 
(c) Birds have pneumatic bones which make their body light for flight. 
12. Number of moles of iron present in 50 g of iron = 50/55.84 =0.895 moles 
Number of moles of sodium present in 50 g of sodium = 50/23 = 2.17 moles 
Number of atoms present in 50 g of iron = 0.895 × 6.022 × 1023 
Number of atoms present in 50 g of sodium = 2.17 × 6.022 ×1023 
Thus, 50 g iron has less number of atoms and moles than 50 g sodium. 
OR 
 
 
Page 4


  
 
CBSE IX | SCIENCE 
Sample Paper – 9 Solution 
 
  
CBSE  
Class IX Science 
Sample Paper – 9 Solution  
 
Section A 
 
1. Leghaemoglobin is a pink-coloured protein present inside the root nodules of 
leguminous plants. 
 
2.  
Macronutrients: Nitrogen, phosphorus (any one) 
Micronutrients: Iron, manganese (any one) 
 
3. Noble gases such as helium, neon, argon and krypton are chemically unreactive and 
exist in the free state as single atoms, i.e. they have one atom each in their molecules. 
Examples: He, Ne, Ar and Kr. So, the atomicity of noble gases is 1. 
 
OR 
 
i. Ammonium sulphate: (NH4)2SO4 
ii. Magnesium carbonate: MgCO3 
 
4. Sound waves produced per second is the frequency of the sound wave. 
As 10 waves are produced per second, the frequency is 10 Hz. 
The time period of a wave is the reciprocal of the frequency. 
?
? ? ?
1
T
f
1
T 0.1 seconds
10
 
So, the time period of a sound wave is 0.1 seconds. 
 
5.  
(a) Collenchyma, a mechanical tissue, provides mechanical support and elasticity.  
(b) It provides tensile strength with flexibility to plant parts such as the stem, 
branches and leaves which allow their easy bending without breaking them. 
(c) Therefore, branches of a tree are able to move and bend freely despite high 
winds. 
  
  
 
CBSE IX | SCIENCE 
Sample Paper – 9 Solution 
 
  
Section C 
 
6.  
(a) Cell membrane/Plasma membrane 
(b) Hypertonic solution 
(c) Cellulose  
 
7.  
 
Hydra 
 
OR 
 
Differences between gymnosperms and angiosperms: 
Gymnosperms Angiosperms 
1. Plants bear naked seeds. 1. Plants bear seeds which develop 
inside the fruit. 
2. Endosperm cells are haploid. 2. Endosperm cells are triploid. 
3. Sporophylls aggregate to form 
cones. 
3. Sporophylls aggregate to form 
flowers. 
4. Examples: Pine, spruce, fir 4. Examples: Sunflower, oak, lily 
 
8. The mass of the ball is (m)= 400 g=
400
0.4
1000
kg ? 
 The initial velocity of the ball is 12 m/s 
i)Thus initial momentum p = m u
p= 0.4 12 4.8 kg m/s.
ii) the velocity of the ball at the highest point (v)=0
The momentum at the highest point of its fligh
?
? ? ?
t will be zero
 
  
 
CBSE IX | SCIENCE 
Sample Paper – 9 Solution 
 
  
OR 
 
Assuming that there is no external unbalanced force working in the horizontal 
direction. 
The momentum of the girl and the cart before the jump is equal to the momentum of 
the girl and the cart after the jump. After the jump, the cart and girl travel with the 
same velocity v. 
 
? ?
? ?
1 1 2 2 1 2
m u m u m m v
40 5 0 40 3 v
200
v 4.65 m/s
43
? ? ?
? ? ? ? ?
? ? ?
 
9. Alloys are homogeneous mixtures of metals and cannot be separated into their 
components by physical methods. But still, an alloy is considered a mixture because 
it shows the properties of its constituents and can have variable composition. 
For example, brass is a mixture of approximately 30% zinc and 70% copper. 
 
10. Factors for crop variety improvement: 
(a) Higher yield 
(b) Improved quality 
(c) Photo-sensitivity and thermo-sensitivity 
(d) Disease resistance 
(e) Pest resistance 
(f) Desirable agronomic characters 
 
11.  
(a) Although Echidna and Platypus lay eggs, they are warm blooded and feed their 
young ones with milk. Hence, they are considered mammals. 
(b) Despite a four-chambered heart, the crocodile is a cold-blooded animal. Hence, it 
is considered a reptile. 
(c) Birds have pneumatic bones which make their body light for flight. 
12. Number of moles of iron present in 50 g of iron = 50/55.84 =0.895 moles 
Number of moles of sodium present in 50 g of sodium = 50/23 = 2.17 moles 
Number of atoms present in 50 g of iron = 0.895 × 6.022 × 1023 
Number of atoms present in 50 g of sodium = 2.17 × 6.022 ×1023 
Thus, 50 g iron has less number of atoms and moles than 50 g sodium. 
OR 
 
 
  
 
CBSE IX | SCIENCE 
Sample Paper – 9 Solution 
 
  
CuSO4   +   NaOH   ?   Cu(OH)2   +   NaSO4 
(15.95 g)    (8 g)          (9.75 g)        (14.2 g)  
Clearly, in this case, 
Total mass of reactants = (15.95 g + 8 g) = 23.95 g 
Total mass of products = (9.75 g + 14.2 g) = 23.95 g 
Hence, the law of conservation of mass is valid here. 
13.  
(a) Difference between Evaporation and Boiling 
 
Evaporation Boiling 
It is a surface phenomenon. It is a bulk phenomenon. 
It is a slow process. It is a rapid process. 
It takes place at all temperatures but 
below the boiling point. 
It takes place at a definite and 
constant temperature. 
 
(b) The four factors affecting the rate of evaporation are: 
? Surface area: Evaporation is a surface phenomenon. If the surface area is 
increased, the rate of evaporation increases.  
? Temperature: With the increase of temperature, more number of particles 
gets enough kinetic energy to go into the vapour state and hence the rate of 
evaporation increases. 
? Humidity: If the humidity of air is high, then the rate of evaporation decreases. 
? Wind speed: With the increase in wind speed, the particles of water vapour 
move away with the wind, decreasing the amount of water vapour in the 
surroundings hence the rate of evaporation increases. 
 
14. If the force is acting perpendicular to the direction of motion of a body, then the angle 
between displacement of the body and the force applied is 90°. 
W = F cos ? × s = F cos 90° × s = 0 
Hence, we say that even though the body is doing work against the frictional forces, 
the man does no work against gravity, as the force of gravity acts vertically 
downwards and the angle between displacement of the suitcase and the force is 90°. 
 
15. i) The speed–time graph is a straight line graph, which means that the speed changes 
in equal intervals of time. Thus, line OA represents uniform acceleration. 
 
ii) We just saw that the graph OA represents acceleration. So, the slope of OA will 
give acceleration.  
Acceleration = slope of OA 
Page 5


  
 
CBSE IX | SCIENCE 
Sample Paper – 9 Solution 
 
  
CBSE  
Class IX Science 
Sample Paper – 9 Solution  
 
Section A 
 
1. Leghaemoglobin is a pink-coloured protein present inside the root nodules of 
leguminous plants. 
 
2.  
Macronutrients: Nitrogen, phosphorus (any one) 
Micronutrients: Iron, manganese (any one) 
 
3. Noble gases such as helium, neon, argon and krypton are chemically unreactive and 
exist in the free state as single atoms, i.e. they have one atom each in their molecules. 
Examples: He, Ne, Ar and Kr. So, the atomicity of noble gases is 1. 
 
OR 
 
i. Ammonium sulphate: (NH4)2SO4 
ii. Magnesium carbonate: MgCO3 
 
4. Sound waves produced per second is the frequency of the sound wave. 
As 10 waves are produced per second, the frequency is 10 Hz. 
The time period of a wave is the reciprocal of the frequency. 
?
? ? ?
1
T
f
1
T 0.1 seconds
10
 
So, the time period of a sound wave is 0.1 seconds. 
 
5.  
(a) Collenchyma, a mechanical tissue, provides mechanical support and elasticity.  
(b) It provides tensile strength with flexibility to plant parts such as the stem, 
branches and leaves which allow their easy bending without breaking them. 
(c) Therefore, branches of a tree are able to move and bend freely despite high 
winds. 
  
  
 
CBSE IX | SCIENCE 
Sample Paper – 9 Solution 
 
  
Section C 
 
6.  
(a) Cell membrane/Plasma membrane 
(b) Hypertonic solution 
(c) Cellulose  
 
7.  
 
Hydra 
 
OR 
 
Differences between gymnosperms and angiosperms: 
Gymnosperms Angiosperms 
1. Plants bear naked seeds. 1. Plants bear seeds which develop 
inside the fruit. 
2. Endosperm cells are haploid. 2. Endosperm cells are triploid. 
3. Sporophylls aggregate to form 
cones. 
3. Sporophylls aggregate to form 
flowers. 
4. Examples: Pine, spruce, fir 4. Examples: Sunflower, oak, lily 
 
8. The mass of the ball is (m)= 400 g=
400
0.4
1000
kg ? 
 The initial velocity of the ball is 12 m/s 
i)Thus initial momentum p = m u
p= 0.4 12 4.8 kg m/s.
ii) the velocity of the ball at the highest point (v)=0
The momentum at the highest point of its fligh
?
? ? ?
t will be zero
 
  
 
CBSE IX | SCIENCE 
Sample Paper – 9 Solution 
 
  
OR 
 
Assuming that there is no external unbalanced force working in the horizontal 
direction. 
The momentum of the girl and the cart before the jump is equal to the momentum of 
the girl and the cart after the jump. After the jump, the cart and girl travel with the 
same velocity v. 
 
? ?
? ?
1 1 2 2 1 2
m u m u m m v
40 5 0 40 3 v
200
v 4.65 m/s
43
? ? ?
? ? ? ? ?
? ? ?
 
9. Alloys are homogeneous mixtures of metals and cannot be separated into their 
components by physical methods. But still, an alloy is considered a mixture because 
it shows the properties of its constituents and can have variable composition. 
For example, brass is a mixture of approximately 30% zinc and 70% copper. 
 
10. Factors for crop variety improvement: 
(a) Higher yield 
(b) Improved quality 
(c) Photo-sensitivity and thermo-sensitivity 
(d) Disease resistance 
(e) Pest resistance 
(f) Desirable agronomic characters 
 
11.  
(a) Although Echidna and Platypus lay eggs, they are warm blooded and feed their 
young ones with milk. Hence, they are considered mammals. 
(b) Despite a four-chambered heart, the crocodile is a cold-blooded animal. Hence, it 
is considered a reptile. 
(c) Birds have pneumatic bones which make their body light for flight. 
12. Number of moles of iron present in 50 g of iron = 50/55.84 =0.895 moles 
Number of moles of sodium present in 50 g of sodium = 50/23 = 2.17 moles 
Number of atoms present in 50 g of iron = 0.895 × 6.022 × 1023 
Number of atoms present in 50 g of sodium = 2.17 × 6.022 ×1023 
Thus, 50 g iron has less number of atoms and moles than 50 g sodium. 
OR 
 
 
  
 
CBSE IX | SCIENCE 
Sample Paper – 9 Solution 
 
  
CuSO4   +   NaOH   ?   Cu(OH)2   +   NaSO4 
(15.95 g)    (8 g)          (9.75 g)        (14.2 g)  
Clearly, in this case, 
Total mass of reactants = (15.95 g + 8 g) = 23.95 g 
Total mass of products = (9.75 g + 14.2 g) = 23.95 g 
Hence, the law of conservation of mass is valid here. 
13.  
(a) Difference between Evaporation and Boiling 
 
Evaporation Boiling 
It is a surface phenomenon. It is a bulk phenomenon. 
It is a slow process. It is a rapid process. 
It takes place at all temperatures but 
below the boiling point. 
It takes place at a definite and 
constant temperature. 
 
(b) The four factors affecting the rate of evaporation are: 
? Surface area: Evaporation is a surface phenomenon. If the surface area is 
increased, the rate of evaporation increases.  
? Temperature: With the increase of temperature, more number of particles 
gets enough kinetic energy to go into the vapour state and hence the rate of 
evaporation increases. 
? Humidity: If the humidity of air is high, then the rate of evaporation decreases. 
? Wind speed: With the increase in wind speed, the particles of water vapour 
move away with the wind, decreasing the amount of water vapour in the 
surroundings hence the rate of evaporation increases. 
 
14. If the force is acting perpendicular to the direction of motion of a body, then the angle 
between displacement of the body and the force applied is 90°. 
W = F cos ? × s = F cos 90° × s = 0 
Hence, we say that even though the body is doing work against the frictional forces, 
the man does no work against gravity, as the force of gravity acts vertically 
downwards and the angle between displacement of the suitcase and the force is 90°. 
 
15. i) The speed–time graph is a straight line graph, which means that the speed changes 
in equal intervals of time. Thus, line OA represents uniform acceleration. 
 
ii) We just saw that the graph OA represents acceleration. So, the slope of OA will 
give acceleration.  
Acceleration = slope of OA 
  
 
CBSE IX | SCIENCE 
Sample Paper – 9 Solution 
 
  
       
2
AB 30 m/s
 a = 2.5 m/s
OB 12 s
iii) the distance travelled = Area of OAB
1
 distance travelled= OC OB
2
1
                                 = 30 12 180 metres.
2
? ? ?
?
? ? ?
? ? ?
 
 
Section D 
16.  
According to Thomson's model of an atom: 
(a) An atom consists of a positively charged sphere, and negatively charged 
electrons are embedded in it. 
(b) The negative and positive charges are equal in magnitude. Hence, the atom has 
no overall positive or negative charge. 
 
 
Properties of Electrons 
? An electron, denoted as e
-
, is a fundamental particle with a negative 
charge. 
? Its properties are independent of the gas in the discharge tube. 
? Its charge is -1. 
? Mass of an electron is extremely small; it is  of the mass of a 
hydrogen atom (9.108 × 10
-28
 g). So, its mass is considered almost 
negligible. (Hydrogen is an atom of the lowest mass). Since the mass of a 
hydrogen atom is 1 u, we can say that the relative mass of an electron 
is  u. 
? The absolute mass of an electron is 9 × 10
-28
 grams. 
? Its charge is 1 unit negative charge, i.e. 1.602 × 10
-19
 coulombs. 
? Tiny electrons revolve around the nucleus of the atom in specific orbits or 
shells.