CBSE Sample Papers for Class 10 Science Paper 5
These Sample papers are part of CBSE Sample Papers for Class 10 Science. Here we have given CBSE Sample Papers for Class 10 Science Paper 5.
Time Allowed: 3 hours
Max. Marks: 80
- The question paper comprises two sections, A and B. You are to attempt both the sections.
- All questions are compulsory.
- All questions of Section-A and B are to be attempted separately.
- There is an internal choice in three questions of three marks each, two questions of five marks each and one question
- (for assessing the practical skills) of two marks.
- Question numbers 1 and 2 in Section-A are one mark question. They 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 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-d are five marks questions. These are to be answered in 70 words each.
- Question numbers 22 to 27 in Section- B are based on practical skills. Each question is a two marks question. These are to be answered in brief.
Why does lack of oxygen in muscles often lead to cramps among cricketers?
Name the method by which Hydra reproduces. Is this method sexual or asexual?
Define the following terms:
- Atomic size
Draw a ray diagram to show the path of the reflected ray corresponding to an incident ray which is direct towards the principal focus of a convex mirror. Mark on it angle of incidence and the angle of reflection. 5. What is meant by biodiversity? List two advantages of conserving forest and wildlife.
During the reaction of some metals with dilute hydrochloric acid, following observations were made.
- The temperature of the reaction mixture rises when aluminium (Al) is added.
- The reaction of sodium metal is found to be highly explosive.
- Some bubbles of a gas are seen when lead (Pb) is reacted with the acid. Explain these observations giving suitable reasons.
In one of the industrial processes used for manufacture of sodium hydroxide, a gas X is formed as by-product. The gas X reacts with lime water to give a compound Y which is used as a bleaching agent in chemical industry. Identify X and Y giving the chemical equation of the reactions involved.
Na, Mg and Alare the elements of the 3rd period of the Modern Periodic Table having group number 1, 2 and 13 respectively. Which one of these elements has the
- highest valency,
- largest atomic radius, and
- maximum chemical reactivity? Justify your answer stating the reason for each.
Based on the group valency of elements, state the formula for the following giving justification for each:
- Oxides of group 1 elements
- Halides of the elements of group 13 and
- Compounds formed when an element of group 2 combines with an element of group 16.
Study the given diagram:
Name the parts ‘A’ and ‘B’ and state one function of each.
How are fats digested in our bodies? Where does this process take place?
In a certain village the sex ratio is very low due to large number of cases
of female infanticide. A man from the same village takes his pregnant wife to the doctor to find out whether the foetus is a girl or a boy. The doctor performs a test and tells them that it is a girl. Answer the following questions based on the above situation:
- Name the technique used by doctor to determine the type of sex of the foetus.
- Which values are disrespected by the doctor in the above situation?
- Suggest two actions to be taken by the administration/society to promote desired related values.
How did Mendel explain that it is possible that a trait is inherited but not : expressed in an organism?
“Evolution and classification of organisms are interlinked”. Give reasons to justify this statement.
If the image formed by a lens for all positions of an object placed in front of it is always erect and diminished, what is the nature of this lens? Draw a ray diagram to justify your answer. If the numerical value of the power of this lens is 10 D, what is its focal length in the Cartesian system?
Three 222 resistors A, B and C are connected as shown in figure. Each 22 of them dissipates energy and can withstand a maximum power of 18 W without melting. Find the maximum current that can flow through the three resistors.
Draw a circuit diagram of an electric circuit containing a cell, a key, an ammeter, a resistor of 212 in series with a combination of two resistors (412 each) in parallel and a voltmeter across the parallel combination. Will the potential difference across the 222 resistor be same as that across the parallel combination of 452 resistors? Give reason.
The given magnet is divided into three parts A, B and C
Name the parts where the strength of the magnetic field is:
How will density of magnetic field lines differs at these parts?
- In the formation of compound between two atoms A and B, A loses two electrons and B gains one electron.
- What is the nature of bond between A and B?
- Suggest the formula of the compound formed between A and B.
- On similar lines explain the formation of MgCl, molecule.
- Common salt conducts electricity only in the molten state. Why?
- Why is melting point of NaCl high?
Elements forming ionic compounds attain noble gas configuration by either gaining or losing electrons from their outermost shells. Give reason to explain why carbon cannot attain noble gas configuration in this manner to form its compounds. Name the type of bonds formed in ionic compounds and in the compounds formed by carbon. Also give reason why carbon compounds are generally poor conductors of electricity:
- State the meaning of functional group in a carbon compound. Write the functional group present in
- ethanol and
- ethanoic acid and also draw their structures
- Write the name and general formula of a chain of hydrocarbons in which an addition reaction with hydrogen can take place. Stating the essential conditions required for an addition reaction to occur write the chemical equation giving the name of the reactant and the product of such a reaction.
- Name the part of brain which controls
- voluntary action,
- involuntary action.
- What is the significance of the peripheral nervous system? Name the components of this nervous system and distinguish between the origin of the two.
- Identify the glands that secrete
- Explain with an example how the timing and amount of hormone secreted are regulated in human body.
- Identify the glands that secrete
- List the parts of the human eye that control the amount of light entering into it. Explain how they perform this function.
- Write the function of retina in human eye.
- Do you know that the corneal-impairment can be cured by replacing the defective cornea with the cornea of the donated eye? How and why should we organise groups to motivate the community members to donate their eyes after death?
- Define electromagnetic induction.
- Two coils P and S are wound over the same iron core. Coil P is connected to battery and key and the coil S is connected to galvanometer. Draw a suitable diagram of this arrangement and write your observations when:
- Current in the coil P is started by closing the key.
- Current continues to flow in coil P.
- Current in coil P is stopped by removing the key.
Explain the reason for such observations.
Briefly explain an activity to plot the magnetic field lines around a bar magnet. Sketch the field pattern for the same specifying field directions. A region A has magnetic field lines relatively closer than another region B. Which region has stronger magnetic field. Give reason to support your answer.
- What is ‘Chipko Movement? Why should we conserve forests?
- Suggest any four changes that you would like to be incorporated in the life-style of students of your age to move towards a sustainable use of available resources.
- An environmentalist on visit to your school suggested the use of three R’s to save the environment. Explain what he meant by three R’s and how you would follow his advice at home.
While performing an experiment, a student observes that when he heats some green crystals in a boiling tube, the colour of the crystals changes to brown and a gas evolves which smells like burning sulphur. Interpret the observations and results.
A student is studying the properties of acetic acid in his school laboratory. List two physical and two chemical properties which he must observe and note in his record book.
The following experiment was set-up to show that a gas is given out during respiration. But there was no rise in the level of water. Why did it happen?
A student is observing a permanent slide showing sequentially the different stages of asexual reproduction taking place in yeast. Name this process and draw diagrams, of what he observes, in a proper sequence.
In an experiment on tracing the path of a ray of light through a rectangular glass slab, four students A, B, C, D used the following values of angle of incidence and the distance between the feet of the two pins (fixed on the incident ray):
(A) (30°, 45°, 60°) and 1 cm
(B) (30°, 45°, 60°) and 6 cm
(C) (20°, 50°, 80°) and 10 cm
(D) (20°, 50°, 80°) and 15 cm
Whose choice is the best choice and why?
The rest positions of the needles in a milliammeter and voltmeter not in use are as shown in Fig. A. When a student uses these in his experiment, the readings of the needle are in the positions shown in Fig. B.
Find the corrected values of current and voltage in the experiment.
While experimentally verifying Ohm’s law a student observed that the pointer of the voltmeter coincides with 15th division when the voltmeter has a least count of 0.05 V. Find the observed reading of voltmeter.
This is due to the conversion of pyruvate to lactic acid in the absence of oxygen.
Hydra reproduces by budding or regeneration. It is a method of asexual reproduction.
- Valency : The combining capacity of an atom is called its valency.
- Atomic Size : Atomic size is the distance between the centre of the nucleus and the outermost shell of an isolated atom.
∠i = angle of incidence
∠r = angle of reflection
Biodiversity refers to the variety of living organisms (aquatic and terrestrial organisms) present in the given ecosystem. Advantages of conserving forest:
- It prevents soil erosion and floods.
- It helps to maintain the water cycle.
Advantages of conserving wildlife:
- It maintains the species diversity.
- It helps in maintaining the ecological balance that is required for supporting life.
- The temperature of the reaction mixture rises when aluminium is added because it is an exothermic reaction.
- Reaction of sodium metal is found to be highly explosive because it is an exothermic reaction.
- When lead is treated with hydrochloric acid, bubbles of hydrogen gas are evolved.
- Pb(s) + 2HCl(aq) — PbCl2(aq) + H2(g)
In the manufacture of sodium hydroxide, hydrogen gas and chlorine gas (X) are formed as by-products. When chlorine gas (X) reacts with lime water, it forms calcium oxychloride (bleaching powder) Y. The reactions are
Y – Calcium oxychloride (bleaching powder)
- Aluminium (Al) has highest valency.
Reason : Valency of Na is 1, Mg is 2, Al is 3
- Sodium (Na) has largest atomic radius.
Reason : As we move from left to right in a period, the atomic radius decreases. Also, increase in nuclear charge pulls the electrons closer to the nucleus reducing the atomic size.
- Sodium (Na) has maximum chemical reactivity.
Reason : Reactivity decreases on moving from left to right in a period.
1. Valency of group 1 element: 1
Valency of oxygen: 2
Oxides of group 1 elements :
Formula of the oxides of group 1 is A2O, where A is the group 1 element and O is oxygen.
2. Valency of group 13 elements: 3
Valency of halogens: 1
Halides of group 13 elements:
Formula of the halides of group 13 is AX3, where A is the group 13
element and X is halogen.
3. Valency of group 2 elements: 2
Valency of group 16 elements: 2
Compounds of group 2 and group 16 elements:
Formula of the compounds of group 2 and 16 is AB, where A is the group 2 element and B is the group 16 element.
A → Stomatal pore
Function : Massive amounts of gaseous exchange takes place in the leaves through these pores for the purpose of photosynthesis.
B → Guard cell
Function : The opening and closing of the stomatal pore is a function of the guard cell.
The small intestine is the site of the complete digestion of fats. The food coming from the stomach is acidic and has to be made alkaline for the pancreatic enzymes to act. It is made alkaline by bile juice secreted by the liver. The upper part of small intestine, also called duodenum, receives bile juice from the liver and the enzyme lipase from pancreas. Bile salts break them down into smaller globules thereby increasing the efficiency of enzyme action and lipase breaks down the emulsified fats. The wall of the small intestine contain glands which secrete intestinal juice. The enzymes present in it finally convert the fats into fatty acids and glycerol. These are absorbed by villi and passed to every cell for obtaining energy.
- The technique used to determine the type of sex of the foetus is called amniocentesis.
- Value for life, professional ethics, gender bias.
- Enactment of law.
→ awareness campaigns about declining sex ratio and its ill effects.
→ education of women.
In Mendel’s experiment, when pure tall pea plants were crossed with pure dwarf pea plants, only tall pea plants were obtained in Fı generation. .
- On selfing the pea plants of F, generation both tall and dwarf pea plants were obtained in F1 generation.
- Reappearance of the dwarf pea plants in F2 generation proves that the dwarf trait was inherited but not expressed in F1 generation.
Different life forms have evolved during the course of evolution. Classification deals with the grouping of these life forms into groups and sub groups based on similarities and differences. The more characteristics any two species have in common, more closely they are related. Thus, classification helps in tracing the evolutionary relationship between the two organisms. Hence, evolution and classification are interlinked.
The nature of the lens is concave, i.e., it is a diverging lens.
The current of resistor A is equally divided in resistors B and C; so maximum current can flow in resistor A.
Power = (current)2 × resistance
= 18w = × 2Ω
= 9 or IA = 3 A
Current in resistor A, IA = 3A
So, current in each of resistor B and C
IB = IC = A = 1.5 A
The circuit is shown in figure. Effective resistance of combination of two resistors (4 Ω each) in parallel is So, the potential difference across 222 resistor is same as that across combination of two resistors.
- Maximum magnetic field is in the region A and C.
- Minimum magnetic field is in the region B.
Reason : A and C are magnetic poles and have maximum number of magnetic field lines which determine the intensity of magnetic field while B is the centre of the magnet and has no magnetic field lines. So, intensity of magnetic field near B is almost zero.
- The nature of the bond between A and B is ionic.
- Formula of the compound is AB,.
- In solid NaCl, the movement of ions is not possible due to its rigid
structure but in aqueous solution or molten state, the ions can move
freely. These free ions are responsible for conduction of electricity.
- NaCl is an ionic compound, considerable energy is required to break strong interionic bonds. So, NaCl has high melting point.
The atomic number of carbon is 6. This means that it has 4 electrons in its outermost shell. To attain noble gas electronic configuration it needs 4 more electrons. The removal of 4 valence electrons requires a huge amount of energy. The cation formed (C4+) will have 6 protons and 2 electrons which will make it highly unstable. Carbon cannot form C4- anion, as its nucleus with 6 protons cannot hold 10 electrons. Thus, carbon achieves noble gas electronic configuration by sharing its 4 electrons with other elements. In ionic compounds, ionic bonds are formed; while in carbon compounds, covalent bonds are formed.
As carbon compounds are covalent in nature, they have no ions or electrons to carry the current. So, they are bad conductors of electricity.
- Functional group is an atom or a group of atoms that forms a bond with a carbon chain.
- Alkenes (CnH2n) and alkynes (CnH2n-2) can undergo addition reaction with hydrogen. Essential conditions required for the addition reaction to occur:
- Multiple bonds (double and triple bonds) must be present between carbon atoms.
- A catalyst such as nickel or platinum must be present.
- Voluntary action-cerebellum;
- Involuntary action-medulla
- The communication between the central nervous system and the other parts of the body is facilitated by the peripheral nervous system. Cranial nerves arises from the brain; spinal nerves arise from the spinal cord.
- Insulin is secreted by pancreas.
- Thyroxin is secreted by thyroid gland.
- The timing and amount of hormone released are regulated by feedback mechanism. For example, if the sugar level in blood rises, they are detected by the cells of pancreas which respond by producing more insulin.
- The pupil: It is the perforation in the iris through which light enters our eyes. The relaxation and contraction of the muscular fibres of the iris regulate the opening and closing of the pupil. Hence, it is the pupil that controls the amount of light entering our eyes.
- The retina is the light-sensing part of the eye which converts the incident light into electrical signals and sends them to the brain.
- Eyes of a dead person can be donated to a person having corneal blindness. It will help him/her to see the world. We can also register ourselves to donate our eyes. The organisations that put up eye donation camps preserve our eyes after our death and donate them to the needy.
1. Electromagnetic induction : The process by which a change in magnetic field in a conductor induces a current in another conductor.
- There is deflection in galvanometer connected with coils due to induced current.
- Deflection becomes zero.
- Deflection in galvanometer is in opposite direction.
- Electromagnetic induction takes place because field is changing.
- Since current becomes stationary, no change in field takes place. So no electromagnetic induction.
- Electromagnetic induction takes place but induced current is in opposite direction.
- Take a drawing sheet and fix it on a smooth table with adhesive tape.
- Place a bar magnet in the middle of the drawing sheet and draw its boundary with a sharp pencil.
- Place a magnetic compass near one end of the magnet (N-pole) and mark the positions of the two ends (N and S-poles) of the compass needle using a sharp pencil.
- Shift the compass from this position and place it in such a way that S-pole of its needle is on the point you marked in previous step for N-pole.
- Again mark the position of the other end (N-pole) of the compass needle.
- Repeat the steps 4 and 5, till you reach the other end (S-pole) of the bar magnet.
- Join all the points with a sharp pencil to get a smooth curve.
- Put the compass at some other points near the N-pole of the magnet and draw another magnetic field lines. Similarly, draw many field lines on both the sides of the bar magnet as shown in figure.
- Observe the pattern of the magnetic field lines.
Result : Magnetic field lines can be drawn around a bar magnet using a magnetic compass. The field lines do not cross each other. Region A has stronger magnetic field. This is due to the strength of the field is proportional to the relative closeness of field lines.
1. ‘Chipko Movement’ (‘Hug the Trees Movement’) originated in a remote
village called Reni in Garhwal during the early 1970s. On a particular day, the women of the village reached the forest and clasped the tree thus preventing the workers from felling the trees. We should conserve forest because:
- There are large number of species, both plants and animals that are found in the forest. However, the range of different life forms is also important in order to preserve the biodiversity we have inherited.
- Forests are the only source of timber, wood, fuel, bamboo, fodder and a rich source of a variety of valuable products.
2. The four changes I would like to incorporate in the life-style of students as a move towards a sustainable use of available resources are as follows:
- Save energy by turning off lights that we are not using.
- Buy recycled paper for decoration and other purposes.
- Use cloth bags in place of plastic bags.
- Use stairs instead of lift wherever possible.
3. By three R’s he meant the following:
- Reduce : means to use less.
- Recycle : means collecting plastic, paper, glass and metal items and recycle these materials to make required things instead of synthesising
- Reuse : means simply reusing things again and again instead of throwing away used ones. I would incorporate the maximum use of three R’s, i.e., reduce, recycle and reuse in my daily life in a move towards sustainable use of our resources.
The green ferrous sulphate crystals change to brown on heating and a colourless gas is evolved (SO2 and SO3). The reaction is decomposition reaction.
- Smells like vinegar,
- Colourless liquid
- Turns blue litmus red
- Gives brisk effervescence with sodium carbonate
There is no rise in the level of water because there is no substance kept in the flask to absorb the gas given out by the seeds.
The process is budding.
The choice of student B is the best.
Reason : The range of angle of incidence should be 30° to 60°. The separation between the feet of the pins should be about 6cm to 8 cm.
Millimeter has negative zero error and voltmeter has positive zero error. Zero correction is always negative of zero error.
Millimeter reading = 38 – (-4) = 38 + 4 = 42 mA
Voltmeter reading = 3.6-(+ 0.4)
= 3.6 – 0.4 = 3.2 V
Least count = 0.05 V
Observed reading of voltmeter = 0.05 × 15 = 0.75 V
We hope the CBSE Sample Papers for Class 10 Science paper 5 help you. If you have any query regarding CBSE Sample Papers for Class 10 Science paper 5, drop a comment below and we will get back to you at the earliest.