CBSE Sample Papers for Class 9 Science Paper 5

CBSE Sample Papers for Class 9 Science Paper 5 are part of CBSE Sample Papers for Class 9 Science. Here we have given CBSE Sample Papers for Class 9 Science Paper 5.

CBSE Sample Papers for Class 9 Science Paper 5

Board	CBSE
Class	IX
Subject	Science
Sample Paper Set	Paper 5
Category	CBSE Sample Papers

Students who are going to appear for CBSE Class 9 Examinations are advised to practice the CBSE sample papers given here which is designed as per the latest Syllabus and marking scheme as prescribed by the CBSE is given here. Paper 5 of Solved CBSE Sample Paper for Class 9 Science is given below with free PDF download solutions.

Time Allowed : 3 Hours
Max. Marks: 80

General Instructions

• The question paper comprises of two Sections, A and B. You are to attempt both the sections.
• All questions are compulsory. However an internal choice will be provided in two questions of 3 marks each and one question of five marks.
• All questions of Section A and all questions of Section B are to be attempted separately.
• Question numbers 1 to 2 in Section A are one-mark questions. These are to be answered in one word or in one sentence.
• Question numbers 3 to 5 in Section A are two-marks questions. These are to be answered in about 30 words each.
• Question numbers 6 to 15 in Section A are three-marks questions. These are to be answered in about 50 words each.
• Question numbers 16 to 21 in Section A are five-marks questions. These are to be answered in about 70 words each.
• Question numbers 22 to 27 in Section B are two-marks questions based on practical skills. These are to be answered in brief

Questions
SECTION-A

Question 1.
Define latent heat of vapourisation.

Question 2.
What are pathogens?

Question 3.
What is gravitational potential energy?

Question 4.
State the properties of colloidal solution.

Question 5.
Give the characteristics of Monera.

Question 6.
Why is crystallisation better than evaporation?

Question 7.
Why do you think it is necessary for you to fasten your seat belts while travelling in your vehicle?

Question 8.
Compare the properties of electrons, protons and neutrons.
OR
Explain the difference between 2O, O₂, and O₃.

Question 9.

1. A stone and feather are thrown from a tower. Both the objects should reach the ground at same time but it does not, give reason.
2. What is the distance covered by a freely falling body during the first three seconds of its motion?

Question 10.
Tabulate the differences between isotopes and isobars.

Question 11.
The temperature at which liquids change into vapours is very high, for example water vapourises at 100°C then how is it possible for water to evaporate at room temperature or at any other temperature?

Question 12.
What is meant by atomic mass, gram atomic mass of an element? Why is the mass have different expressions i.e.,‘u’ and ‘g’?
OR
With the help of an activity in daily life, how can you prove that atoms are divisible.

Question 13.
What is acid rain? Give its harmful effects.

Question 14.
What would happen to the life of a cell if there was no Golgi apparatus? What would happen if the plasma membrane ruptures or breaks down?

Question 15.
Aman saw a sudden rise in the electricity bill for the month of January. He did the survey of electronic equipments used in his house and found that the electric room heater was used for longer hours to keep the room warm. The power of electric heater was 18000 watts. He suggested to use the heater intermittently and keep the warm air trapped in the room.

1. Convert the power of room heater into kW and if it is used for one hour what is the work done by it.
2. Convert 1 kW h into joules.
3. What value of Aman is reflected in this act?

Question 16.
State all three Newton’s law of motion. Explain inertia and momentum.

Question 17.

1. Cite an experiment to show that sound needs a material medium for its propagation.
2. Why is sound waves called longitudinal waves?

Question 18.
(a) Explain the following:

1. An object increases its energy when raised through some height.
2. Energy is neither created nor destroyed then from where do we get energy.
3. When we push the wall, the wall does not move and no work is done.

(b) State and explain one example where

1. Kinetic energy is present in a body and is used.
2. Potential energy is present in a body and is used.

Question 19.
Give reasons:

1. A gas fills the vessel completely in which it is kept.
2. A gas exerts pressure on the walls of the container.
3. A wooden table should be called a solid.
4. We can easily move our hand in air but to do the same through a solid block of wood we need a karate expert.

OR

1. Why is air considered as a mixture and not compound?
2. How can you prove that water is a compound?

Question 20.
(a) How can we get speed from distance-time graph?
(b) Represent a graph that shows the following:
(i) Uniform speed
(ii) Non-uniform speed
(iii) Stationary object

Question 21.
What are the different ways used for the treatment and prevention of diseases?

SECTION-B

Question 22.
An experiment was set up to determine the percentage of water imbibed by the raisins. If the mass of dry raisins was 40 g and the mass of wet raisins was 45 g. Calculate the percentage of water imbibed by the raisins.

Question 23.
The radicle and plumule grows from the seed that is germinating. What does it become on maturity?

Question 24.
The following diagram gives the structure of a nerve cell. Identify the parts labelled as A, B and C respectively.

Question 25.
Why should magnesium ribbon be cleaned before burning in air?

Question 26.
Why does brass react with dilute hydrochloric acid and is corroded in the rainy season to form CUCO₃ . CU(OH)₂?

Question 27.
Why is the density of water at 80 °C less than its density at 30° C?

Answers
SECTION-A

Answer 1.
Latent heat of vapourisation is the heat energy required to change 1 kg of a liquid to vapour form at one atmospheric pressures, at its boiling point.

Answer 2.
The disease causing microbes are called pathogens. Example, bacteria, virus, fungi, worms.

Answer 3.
The gravitational potential energy of an object at a point above the ground is defined as the work done to raise the object from the ground to that point against gravity.
Mathematically, G.P.E. = mgh

Answer 4.
Properties of colloidal solution:

• It is a homogenous mixture that appears to be heterogenous having particle size between 1 nm to 100 nm.
• Size of particles is very small, cannot be seen with naked eyes.
• It scatters a beam of light and show Tyndall effect.
• They are stable, as the particles do not settle when left undisturbed.

Answer 5.

1. They are unicellular, do not have a defined nucleus.
2. They may have cell wall or may not have cell wall.
3. Mode of nutrition is either autotrophic or heterotrophic.
4. They reproduce by fission process mostly by binary fission.

Answer 6.
Crystallisation is a process that separates a pure solid in the form of its crystals from a solution.
Crystallisation is better than evaporation because during evaporation

• Some solids may decompose or some like sugar may get charred on heating to dryness.
• Some impurities may remain dissolved in the solution even after filtration which on evaporation contaminates the solid.

Answer 7.
While we are travelling in a moving car, our body remains in the state of rest with respect to the seat. But when driver apply sudden breaks or stop the car our body tends to continue in the same state of motion because of its inertia. Therefore, this sudden break may cause injury to us by impact or collision. Safety belt exerts a force on our body to make the forward motion slower and thus protects us from injury.

Answer 8.

Electrons	Protons	Neutrons
(i) Negatively charged	Positively charged	No charge
(ii) Mass is negligible [\(\frac { 1 }{ 1800 } \) times of protons ]	Mass is 1 a.m.u.	Mass is 1 a.m.u.
(iii) Present outside the Nucleus and attracts positive charge	Present in the nucleus and attracts negative charge	Present in the nucleus of an atom

OR
2O₂ → It represents 2 atoms of oxygen (cannot exist independently).
O₂ → It represents one molecule of oxygen (made up of 2 atoms, can exist freely).
O₃ → It represents one molecule of ozone (made up of 3 atoms, it can exist independently).

Answer 9.

1. As per the motion of object due to ‘g’ gravitational pull of earth, both the bodies are acted upon by the same force of earth but the stone will fall first and then the feather. Feather being lighter, experiences greater air resistance, so it will reach later.
2. Here initial velocity u = 0, acceleration a = g = 9.8 ms^-2 and t = 3 s
   ∴ Vertically downward distance covered, h = \(\frac { 1 }{ 2 }\) gt²
   = \(\frac { 1 }{ 2 }\) × (9.8) × 3² = 44.1 m

Answer 10.

Isotopes	Isobars
• Atoms of same element.	Atoms of different element.
• Have same atomic number but different mass number.	Have different atomic number but same mass number.
• Number of protons and electrons are same in their atoms.	Number of protons and electrons are not same in their atoms.

Answer 11.
The molecules of water present on the surface of the exposed area which are in very small fraction, gains the energy from the surroundings. With this higher kinetic energy they are able to break the forces of attraction between them and hence get converted into vapour state.

This phenomenon of change of a liquid into vapours that takes place at any temperature below its boiling point is called evaporation.

Answer 12.
Atomic mass refers to the mass of an atom. One unit atomic mass is exactly equal to one twelfth of the mass of an atom of C-12-isotope, which is taken as a universal standard. It is expressed in u.
Gram atomic mass: When the atomic mass of an element is expressed in grams, it is called the gram atomic mass of the element.
The mass of atoms, molecules is expressed in V and the mass of moles i.e., molar mass is expressed in g. Thus, while considering atomic mass, V is used but when mass is expressed in terms of moles of a substance ‘g’ is used.

OR
Activity:

• Take a scale, rub it on hair and try to attract small bits of paper.
• Now divide the bits of paper further into smaller pieces.
• Again bring the charged scale near this pieces of paper.
• You will observe that the bits of paper still get attracted.

Conclusion: This activity shows that atom contains charges and these charges are opposite in nature which shows the attraction. Here both scale and paper are oppositely charged and hence attract each other. Also, every atom has at least one sub-atomic particle.

Answer 13.
The gases released due to combustion of fossil fuels are SO₂, NO₂, CO₂, these gases remain
suspended in the air. When it rains the rainwater mixes with these gases to form sulphuric acid, nitrous acid, carbonic acid and came down on the surface of the earth in the form of acid rain.
Harmful effects of acid-rain:

1. It corrodes statues, monuments of marble, building etc.
2. It makes the soil acidic.
3. It damages crops, plantations.

Answer 14.
Golgi apparatus has the function of storage, modification and packaging of the products in the vesicles. If there were no Golgi bodies, packaging and dispatching of materials synthesised by the cell will be stocked and the cell functioning is affected.
If plasma membrane ruptures or breaks down then molecules of some substances from the cell will freely move in and out.

Answer 15.

1. The power of room heater is 18 kW
   Work done (W) = ?, t = 1 hour, P = 18,000 W
   p = \(\frac { W }{ t }\) ∴ W = p × t
   = 18000 × 3600
   W= 64800000 J
   W= 6.48 × 10⁷ J
2. 1 kWh = 3.6 × 10⁶ J
3. Aman showed the value of an aware citizen.

Answer 16.

• Newton’s Ist law of motion: An object remains in a state of rest or of uniform motion in a straight line unless acted upon by an external unbalanced force.
• Newton’s IInd law of motion: The rate of change of momentum of an object is proportional to the applied unbalanced force in the direction of the force.
• Newton’s IIIrd law of motion: To every action, there is an equal and opposite reaction and they act on two different bodies.
• Inertia: The natural tendency of an object to resist a change in their state of rest or of uniform motion is called inertia.
• Momentum: The momentum of an object is the product of its mass and velocity and has the same direction as that of the velocity. Its S.I. unit is kg m/s.
  p = m × v

Answer 17.
1. Description:
Take an electric bell and an air tight glass bell jar. The electric bell is suspended inside an , air tight glass jar which is connected to a vacuum pump.

Working:

• When we press the switch, we’ll be able to hear the bell.
• When the air in the jar is pumped out gradually, the sound becomes feeble although the same amount of current is flowing through the bell.
• When the air is removed completely, we’ll not be able to hear the sound of the bell.

Conclusion:
This experiment shows that sound requires a medium for its propagation.
2. When sound wave travels, the air molecules oscillate in the same direction as that of the propagation of sound waves. Hence they are called longitudinal waves.

Answer 18.
(a)

1. An object having mass ‘M’, when raised through certain height, energy is applied on it, this energy gets transformed and is gained by the stone, hence its energy increases.
2. Energy is present in every object in some or other form, it exists in sun, planet, wind, water etc. The energy gets transformed from one form to another because of its transformation we get the useful energy.
   For e.g. Sun’s energy is converted by plants (by chemical reaction) into food energy. We eat green vegetables products of plants and energy enters our body.
3. Work is said to be done, when force is applied on the body and it moves to certain distance in the direction of applied force. When a wall is pushed, there is no displacement and thus work done is zero.

(b) Kinetic energy is the energy present in a body by the virtue of its motion. When water is stored in a dam at a particular height, we say it has maximum potential energy as the water is present at a height. When this water is allowed to fall down from that certain height, it is said to possess kinetic energy. When the water falls on a turbine, the paddle wheel rotates to rotate the turbine. Hence kinetic energy of water is used to push or rotate the turbine which is further used to produce the electricity.

Answer 19.

1. The molecules of gas have high kinetic energy due to which they keep on moving in all the directions and hence fills the vessel completely in which they are kept.
2. A gas exerts pressure on the walls of the container because the molecules of gas are in constant random motion due to high kinetic energy. These molecules constantly vibrate, move and hit the walls of the container thereby exerting pressure on it.
3. The molecules/particles of a wooden table are tightly packed with each other, there is no intermolecular space, it cannot be compressed, it cannot flow, all these characteristics are of solid state of matter. So, wooden table should be called a solid.
4. We can easily move our hand in air but to do the same through a solid block of wood we need a karate expert. It is because the molecules of air has less forces of attraction between them and a very small external force can separate them and thus our hand can pass through it. But in the case of solids, the molecules have maximum forces of attraction and the particles are tightly bound due to this force. Hence large amount of external force is required to pass our hand through a solid.

OR
1. Air is considered as a mixture because it exhibits the following properties:

• Each component present in air retains its properties.
• Each component can be separated by simple physical processes.
• The components do not have any fixed proportion. All gases are present in different amounts. Example, in a green area-more oxygen and water vapour is present while nearer industrial area-air consists of lot of impurities and smoke suspended in it.

2. Water is considered a compound because if we pass electricity through it then at two different electrodes, we get two different gases, i.e. oxygen and hydrogen. The ratio of oxygen: hydrogen gases collected is 1 : 2 by the number of molecules.

• The properties of oxygen and hydrogen gases are entirely different from that of liquid water.
• The ratio of oxygen: hydrogen combination in water is always constant i.e., 1 : 2 by volume and 1 : 8 by mass.
• To separate the components of water, we need an electrolytic cell, and it is not a simple process. We can separate the components of water, i.e. H, and O₂ gas by simple physical processes.

Answer 20.
(a) Let us assume that an object moves with a uniform speed. The distance-time graph will be a straight line as shown along side:

Let d₁ be the distance covered in time t₁
Let d₂ be the distance covered in time t₂
∴ d₂ – d₁ will be the distance covered in t₂ – t₁

Conclusion:
To find the speed from distance-time graph we can get its slope which is equal to the speed of the object.
(b) Time is taken on the x-axis as it is an independent quantity and distance which is dependent quantity is are taken along y-axis.

Answer 21.
Principles of treatment of diseases are:

• To reduce the effect of for diseases.
• To kill the cause of diseases, i.e. to kill the microbes like bacteria, fungi, protozoa.

Principles of prevention are:

1. General ways: It is related to the prevention towards the exposure of microbes. This can be done in following ways:
   • For avoiding airborne infections – Avoid visiting public places, cover your nose and mouth while sneezing or coughing.
   • For waterborne infection – Drink safe, clean and boiled water. Vi
   • For vector-borne diseases – Keep the surroundings clean, keep food and water . covered and clean. Do not allow any water to stand, as it becomes a breeding ground for mosquitoes.
   • Self immunity – It is a self-defence mechanism in our body that can fight and kill the harmful microbes that enter our body.
2. Specific ways: By giving vaccines, childhood immunisation that is given to the children for preventing infections and diseases.

SECTION-B

Answer 22.
\(\frac { (45-40)g }{ 40g }\) × 100 = 12.5 %
∴ 12.5% of the weight of wet raisins which is equal to the % age of water imbibed by the raisins is due to water.

Answer 23.
The radicle becomes the root and the plumule becomes the shoot.

Answer 24.

• A – Axon
• B – Dendrite
• C – Cytoplasm Cyton.

Answer 25.

• To remove the impurities from the magnesium ribbon and use it in pure form.
• Magnesium has the tendency to form a layer of magnesium oxide on the strip.

Answer 26.
Brass is an alloy of copper and zinc. It is a homogeneous mixture. The combining elements retain their properties. Hence copper present in brass reacts with the carbonates and moisture present in the air to form CuCO₃ . Cu(OH)₂.

Answer 27.
The density of a liquid or a gas changes with change in temperature. With increase in the temperature its density of liquids will decreases gradually.

We hope the CBSE Sample Papers for Class 9 Science Paper 5 help you. If you have any query regarding CBSE Sample Papers for Class 9 Science Paper 5, drop a comment below and we will get back to you at the earliest.