Please refer to Class 10 Science Sample Paper Set g below provided with solutions. All Class 10 Science Sample Paper have been prepared based on the latest syllabus and examination guidelines issued by CBSE, NCERT and KVS. All questions have been provided with solutions.
Class 10 Science Sample Paper Set g
Time: 3 Hours Maximum Marks: 80
(i) The question paper comprises four sections A, B, C and D. There are 36 questions in the question papers. All questions are compulsory.
(ii) Section–A – question no. 1 to 20 – all questions and parts thereof are of one mark each. These questions contain multiple choice questions (MCQs), very short answer questions and assertion – reason type questions. Answers to these should be given in one word or one sentence.
(iii) Section–B – question no. 21 to 26 are short answer type questions, carrying 2 marks each. Answers to these questions should in the range of 30 to 50 words.
(iv) Section–C – question no. 27 to 33 are short answer type questions, carrying 3 marks each. Answers to these questions should in the range of 50 to 80 words.
(v) Section–D – question no. – 34 to 36 are long answer type questions carrying 5 marks each. Answer to these questions should be in the range of 80 to 120 words.
(vi) There is no overall choice. However, internal choices have been provided in some questions. A student has to attempt only one of the alternatives in such questions.
(vii) Wherever necessary, neat and properly labeled diagrams should be drawn
Question 1. Why does the colour of copper sulphate solution change when an iron nail is dipped in it? (1 Marks)
What do you mean by exothermic reaction?
Answer. Iron has displaced or removed another element copper from copper sulphate solution. Iron nail becomes brownish while blue colour of copper sulphate fades.
Reaction in which heat is released along with the formation of products.
Question 2. What will happen if a solution of sodium hydrogen carbonate is heated? Give the equation of the reaction involved? (1 Marks)
Answer. 2NaHCO3 ——> Na2CO3 + H2O + CO2
Sodium hydrogen carbonate Sodium carbonate
Question 3. A non-metal X exists in two different forms Y and Z. Y is the hardest natural substance whereas Z is a good conductor of electricity. Identify X, Y and Z. (1 Marks)
Answer. X- Carbon, Y- Diamond, Z- Graphite.
Question 4. Give a test that can be used to differentiate between saturated and unsaturated hydrocarbons? (1 Marks)
Answer. Add bromine water , saturated hydrocarbons do not react whereas unsaturated hydrocarbon will decolourise bromine water.
Question 5. Which of the following is true, if element of group 2 of periodic table reacts with the element of group17? (1 Marks)
a) The compound formed conducts electicity.
b) Ionic bonding takes place to form the compound.
c) No bonding will take place.
d) Both (a) and (b).
e) None of these.
Answer. Option (d) Both a and b.
Question 6. Write any one limitation of Newland’s Law of Octaves. (1 Marks)
Answer. * It was not applicable throughout the arrangements. It was applicable upto calcium only. Those elements that were discovered after Newlands’ octaves did not follow the law of octaves.
* The position of Cobalt and nickel in the group of the elements (F, Cl) of different properties could not be explained.
* Placing of Iron far away from cobalt and nickel , which have similar properties as iron, could not be explained. (any one)
Question 7. What is emulsification of fats? (1 Marks)
What is ‘translocation’ in plant?
Answer. Breakdown of large globule fats into smaller fats droplets .
The movement of soluble materials , products of photosynthesis from leaves to other tissues throughout the plant.
Question 8. The sky appears dark instead of blue to an astronaut. State its reason. (1 Marks)
Answer. Because scattering does not take place at very high altitude due to the absence of atmosphere.
Question 9. An electric bulb is connected to a 220 V generator. The current is 0.50 A. What is the power of the bulb? (1 Marks)
A. 1100 W.
B. 1.10 W.
C. 0.10 W.
D. 110 W.
What does an electric circuit mean?
Answer. P= VI
= 22O V ×0.50 A= 110J/s = 110 W.
A CONTINUOUS AND CLOSED PATH OF AN ELECTRIC CURRENT.
Question 10. What are magnetic field lines? (1 Marks)
State one main difference between alternating current and direct current?
Answer. It is defined as the path along which the unit North pole (imaginary ) tends to move in a magnetic field if free to do so.
AC reverses its direction periodically whereas DC always flows in one direction.
Question 11. John is playing with a coil as a Solenoid, Galvanometer and Bar magnet in laboratory during practical period. He observed the Galvanometer gives deflection in some conditions. He draws conclusion from this activity.
i) Name the phenomenon associated with this activity. Name the scientist who has invented this effect. (1 Marks)
ii) Why bulb glows in second coil when switch is on in the first coil without contact with the second coil in figure 2. (1 Marks)
iii) What will be the effect on deflection in galvanometer if solenoid is replaced by thicker and longer solenoid ? (1 Marks)
Answer. (i) Electromagnetic induction, Faraday.
(ii) Mutual induction (EMI)
(iii) Deflection increases in both cases
For question numbers 12, 13 and 14, two statements are given- one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer to these questions from the codes (a), (b), (c) and (d) as given below:
a) Both A and R are true, and R is correct explanation of the assertion.
b) Both A and R are true, but R is not the correct explanation of the assertion.
c) A is true, but R is false.
d) A is false, but R is true.
Question 12. Assertion: Acquired trait cannot be passed from one generation to next generation. (1 Marks)
Reason: Inaccuracy during DNA copying of acquired trait is minimum.
Answer. c) A is true, but R is false.
Question 13. Assertion: Conductors allow the current to flow through themselves. (1 Marks)
Reason: They have free charge carriers.
Answer. a) Both A and R are true, and R is correct explanation of the assertion.
Question 14. Assertion: Twinkling of stars is due to the fact that refractive index of the earth’s atmosphere fluctuates. (1 Marks)
Reason: Dispersion is due to Tyndall effect.
Answer. c) A is true but R is false.
|Answer the questions (15, 16, 17, 18, 19 and 20) that follow on the basis of your understanding of the following source and the related studied concepts.|
Question 15. RESPIRATION
In human beings, air is taken into the body through the nostrils. The air passing through the nostrils is filtered by fine hairs that line the passage. The passage is also lined with mucus which helps in this process. From here, the air passes through the throat and into the lungs. Rings of cartilage are present in the throat. These ensure that air passage does not collapse. Within the lungs, the passage divides into smaller and smaller tubes which finally terminate in balloon -like structure called alveoli. The alveoli provide a surface where the exchange of gases can take place. The walls of the alveoli contain an extensive network of blood -vessels. As we have seen in earlier tears, when we breathe in, we lift our ribs and flatten our diaphragm, and the chest cavity becomes larger as a result. Because of this, air is sucked into the lungs and fills the expanded alveoli.
(i) Which is the correct sequence of air passage during inhalation? (1 Marks)
b) Nasal passage—trachea—pharynx—larynx—alveoli.
Answer. c) Nostrils—pharynx—larynx—trachea—alveoli.
(ii) What happens to the air as it passes through the nasal passage? (1 Marks)
a) Filtered in the nostrils.
c) Moistened by mucus.
b) Warmed to the body temperature.
d) All of these.
Answer. d) All of these.
(iii) Which feature of alveoli makes it suitable for the exchange of gases? (1 Marks)
a) They form a very large surface area.
b) They have a very thin wall.
c) They are covered with blood vessels.
d) All of these.
Answer. d) All of these.
Question 16. Define lung capacity. (1 Marks)
Answer. The maximum air that can be held in the two lungs at any time. It is about 6000ml.
Question 17. (i) At noon the sun appears white as (1 Marks)
a) Light is least scattered.
b) All the colours of the white light are scattered away.
c) Blue colour is scattered the most.
d) Red colour is scattered the most.
Answer. a) Light is least scattered.
(ii) The danger signals installed at the top of tall buildings are red in colour. These can be easily seen from a distance because among all other colours, the red light (1 Marks)
a) Is scattered the most by smoke or fog.
b) Is scattered the least by smoke or fog.
c) Is absorbed the most by smoke or fog.
d) Moves fastest in air.
Answer. b) Is scattered the least by smoke or fog.
(iii) A student sitting at last bench can read the letters written on the blackboard but is not able to read the letters written in his textbook. Which of the following statements is correct? (1 Marks)
a) The near point of his eyes has receded away.
b) The near point of his eyes has come closer to him.
c) The far point of his eyes has come closer to him.
d) The far point of his eyes has receded away.
Answer. a) The near point of his eyes has receded away.
(iv) The blue colour of water in deep sea is due to (1 Marks)
a) The presence of some plants found in water.
d) Reflection of sky in water.
c) Scattering of light.
d) Due to absorption of blue colour of light.
Answer. c) Scattering of light.
18. Human being involves two parents in sexual reproduction. One is male and another is female. Male and female differ from each other on the basis of reproductive organs. (1× 4 marks)
(i) Out of the given choice which one is not the part of female reproductive system?
a) Fallopian tube.
d) Vas deferens.
Answer. d) Vas deferens.
(ii) Reproduction is not necessary to maintain the life of an individual, unlike other life processes such as nutrition, respiration or excretion. Still an individual wastes energy for reproduction.
State the above statement is true or false.
(iii) What will be the effect if Prostate gland is removed from the male reproductive system?
a) Fewer sperms will be formed.
b) Fewer sperms will be stored.
c) Less testosterone will be produced.
d) Sperms will become less active.
Answer. d) Sperms will become less active.
(iv) Which of the following statement is incorrect?
a) Placenta allows exchange of materials between mother and foetus.
b) The foetal part of placenta consists of the cells of the chorion which produce projections called chorionic villi.
c) Antibody cannot cross the placenta from mother to foetus.
d) Placenta secretes pregnancy hormones required for supporting foetal growth and metabolic changes in mother during pregnancy.
Answer. c) Antibody cannot cross the placenta from mother to foetus.
Question 19. ELECTRIC MOTOR
Gatimaan Express is India’s first semi-high-speed train that runs between Delhi and Jhansi. It operates at a maximum speed of 160km/h (99 mph) and is currently the fastest train in India. The train takes 265 minutes to cover 403 km (250 miles) journey from Hazrat Nizamuddin station to Jhansi Junction station.
(i) Name the type of energy used to run this train. (1 Marks)
Answer. Electric energy.
(ii) Commercial electric motors do not use (1 Marks)
a) An electromagnet to rotate the armature.
b) Effectively large number of turns of wire in the current carrying coil.
c) A permanent magnet to rotate the armature.
d) None of these.
Answer. b) Effectively large number of turns of wire in the current carrying coil.
(iii) Write two uses of electric motor in your daily life. (1 Marks)
Answer. Fan, mixer grinder
Question 20. Which of the following statements are applicable for electric motor? (1 Marks)
a) It converts electrical energy to mechanical energy.
b) It works on the basis of Fleming’s left-hand rule.
c) It works on the magnetic effect of current.
d) All of these.
Answer. d) All of these.
Question 21. What happens when sodium sulphate reacts with barium chloride? (2 marks)
a) What was the colour of the precipitate? Can you name the compound precipitated?
b) Write the balanced chemical equation for this reaction.
Answer. (a) It forms a white precipitate of Barium sulphate.
(b) NaSO4 (aq) + BaCl2 (aq) —-BaSO4 (s) + 2NaCl(aq)
Sodium Barium Barium Sodium
sulphate chloride sulphate chloride
Question 22. a) Why is sodium kept immersed in kerosene oil? (2 marks)
b) What do you mean by the term anodizing?
Answer. (a) Because it reacts so vigorously and catch fire if kept in open.
(b) Process of forming a thick oxide layer of aluminium when exposed to air.
Question 23. What is hydrogenation? What is its industrial application? (2 marks)
The number of carbon compounds is more than those formed by all other elements put together. Justify the statement by giving two reasons.
Answer. Hydrogenation is a process of addition of hydrogen. Unsaturated hydrocarbons are added with hydrogen in presence of nickel and palladium catalysts to give saturated hydrocarbons
Application- In the hydrogenation of vegetable oils, which contains long chain of unsaturated carbons.
Carbon has the unique ability to form bonds with other atoms of carbon, giving rise to large number of molecules – property of Catenation.
Carbon has valency of four, it is capable of bonding with four other atoms of carbon or atoms of some other element – property of Tetravalency
Question 24. What is the meant by blood pressure. Name the instrument to measure blood pressure. (2 marks)
What is the role of acid in our stomach?
Answer. The force that blood exerts against the wall of a vessel is called blood pressure. Instrument is Sphygmomanometer.
Acid creates an acidic medium which facilitates the action of protein digesting enzyme pepsin. Also it sterilizes food by killing pathogens and other microbes
Question 25. a) When a 12V battery is connected across an unknown resistor, there is a current of 2.5mA, in the circuit. Find the value of the resistance of the resistor. (2 marks)
b) Why were copper and aluminum wires usually employed for electricity transmission?
Answer. (a) According to Ohm’s law V= IR,
= 4800 Ω=4.8 kΩ.
(b) Copper and aluminium wires have low resistivity. They are good conductors of electricity.
Question 26. What are trophic levels? Give an example of a food chain and state the different trophic levels in it. (2 marks)
Answer. The various steps in food chain at which transfer of food energy takes place are trophic levels.
Example : Food chain operating in a grassland (ANY OTHER EXAMPLE ALSO MAY BE TAKEN)
1. Grass – 1st trophic level
2. Insects- 2nd trophic level
3. Frogs- 3rd trophic level
4. Birds – 4th trophic level
Question 27. a) Translate the following statements into chemical equations and then balance them. (3 marks)
i) Potassium metal reacts with water to give potassium hydroxide and hydrogen gas.
ii) Hydrogen sulphide gas burns in air to give water and Sulphur dioxide.
b) Define Rancidity.
Answer. a) i) 2K(s) + 2H2O(l) — 2KOH(aq) + H2 (g)
ii) 2H2S(g) + 3 O2 (g) – 2 H2O(l) + 2 SO2 (g)
b) The oxidation of fat containing food items is called rancidity.
Question 28. Give reasons for the following: (3 marks)
a) School bells are made up of metals.
b) Aluminum oxide is considered as an amphoteric oxide.
c) Copper vessels get a green coat when left exposed to air in the rainy season?
Answer. Because metals are sonorous, i.e, they produce sound when struck with a hard substance.
b) Because it reacts with acids as well as bases to produce salt and water.
c) Copper vessels react with carbon dioxide, oxygen and moisture to form green coloured basic copper carbonate.
Question 29. a) F, Cl, and Br are the elements having seven valence electrons. Which of these (3 marks)
(i) Has the largest atomic radius?
(ii) Is most reactive? Justify your answer stating reason for each.
b) How will the tendency to gain electrons change as we go from left to right across a period?
Answer. (a) i) Bromine has largest atomic radius because it has four shells 2,8,18,7 Fluorine is most reactive because it is smallest in size and can gain electron easily.
ii) Tendency to gain electrons increases from left to right in a period because atomic size goes on decreasing and effective nuclear charge increases.
Question 30. List in tabular form three difference between arteries and veins. (3 marks)
a) “The breathing cycle is rhythmic whereas exchange of gases is a continuous process.” Justify this statement.
b) How opening and closing of stomata takes place?
Answer. Arteries carry oxygenated blood away from heart except pulmonary heart. Mostly deeply situated in the body. Thick walled highly muscular except arteries of cranium and vertebral column.Veins carry deoxygenated blood towards the heart except pulmonary vein. Superficial and deep in location. Thin walled.
a) Breathing cycle involves inhalation and exhalation of air due to alternate expansion and contraction of thoracic cavity. Thus it is rhythmic. Whereas exchange of gases takes place between blood and each and every cell by diffusion.
b) When water flows into the guard cells, it swells up and the stomata pores open up and vice versa.
Question 31. How is the sex of the child determined in human beings? (3 marks)
Answer. For explanation of gametes
Page no 146 of textbook For figure and cross
Question 32. a) Define 1 diopter of power of a lens. (3 marks)
b) Light enters from air to glass having refractive index 1.50. What is the speed of light in the glass? (The speed of light in vacuum is 3× 108 m/s.?
Draw a ray diagram and also state the position, the relative size and the nature of image formed by a concave mirror when the object is placed at the center of curvature of the mirror.
Answer. Power of lens is defined as the reciprocal of its focal length.
P= 1/f. Unit is 1m-1.
b) Refractive index of a medium nm = Speed of light in vacuum/ speed of light in medium=c/v
V= c/nm = 3 × 108 / 1.50 = 2 × 108 m/s.
Refer page 166 of textbook fig. 10.7 (c ) For position
For nature of image – Real ,inverted and of same size
Question 33. What is meant by spectrum of white light? How can we recombine the components of white light after a prism has separated them? Draw a diagram to illustrate it. (3 marks)
Answer. The coloured pattern VIBGYOR formed by a prism by splitting the incident white light is called a spectrum. By having two prisms, inverted to each other , one can recombine the light to get white light again.
Refer figure 11.6 page 193
Question 34. a) List two advantages of growing grapes or banana plants through vegetative propagation. (5 marks)
b) List the parts of human male reproductive system which contribute fluid to the semen. State any one advantage semen offer to the sperms.
c) Why is it said that sexual reproduction promotes diversity of characters in the offspring?
Answer. Two advantages:
This ensures the preservation of the traits of the parent plants.
As these plants do not produce viable seeds, vegetative propagation is advantageous for them.
b) Prostate gland and seminal vesicles discharge fluid in the Vas deferens.
Advantage- It makes the transportation of sperms easier.
OR it also provides nutrition to the sperms.
c) Because sexual reproduction involves the fusion of two gametes from two distinct individuals which leads to variation.
Question 35. a) Define a universal indicator. Mention its one use. (5 marks)
b) Solution A gives pink colour when a drop of Phenolphthalein indicator is added to it. Solution B gives red colour when a drop of Methyl orange is added to it. What type of solutions are A and B and which one of the solutions A and B will have higher pH value.
c) Name one salt whose solution has pH more than 7 and one salt whose solution has pH less than 7.
What is water of crystallization? Write the common name and chemical formula of a commercially important compound which has ten water molecules as water of crystallization. How is this compound obtained and write the chemical equation also. List any two uses of this compound.
Answer. Universal indicator is a solution of many indicators, which shows different colour changes for solutions with different pH values. It is used to test whether a solution is an acid or a base.
b) As solution A turns pink when phenolphthalein indicator is added it is a base.Solution B is an acid.
The pH value of A is higher as compared to that of B because basic solution has higher pH value
c) Sodium carbonate has pH more than 7 and Ammonium chloride has a pH less than 7.
Water of crystallization is the fixed number of water molecules present in one formula unit of a salt.
Washing soda Na2CO3.10H2O.
Nacl (s) + H2O(l) + CO2 (g) + NH3 (g) —— NH4Cl (g) + NaHCO3 (s)
2NaHCO3 (S) ON HEATING ———- Na2CO3 (s) + H2O (l) + CO2(g)
Na2CO3(s) + 10H2O(l) —— Na2CO3.10H2O (s)
Uses : 1) Used in glass, soap and paper industries.
2) Used for removing permanent hardness of water.
Question 36. a) The potential difference between two points in an electric circuit is 1V. What does it mean? Name a device that helps to measure the potential difference across a conductor. (5 marks)
b) Why does the connecting cord of an electric heater does not glow while the heating element does?
c) Electric resistivities of some substances at 200 C are as given below:
Silver : 1.60 ×10-8 Ω-m
Copper : 1.62 ×10-8 Ω-m
Tungsten : 5.2 ×10-8 Ω-m
Iron : 10.0 ×10-8 Ω-m
Mercury : 94.0 ×10-8 Ω-m
Nichrome: 100 ×10-6 Ω-m
Answer the following questions using following data:
(i) Among silver and copper, which one is a better conductor and why?
(ii) Which material would you advise to be used in electrical heating devices and why?
A household uses the following electric appliances.
(i) Refrigerator of rating 400W for 10 h each day.
(ii) Two electric fans of rating 80W each for 6 h daily.
(iii) Six electric tubes of rating 18 W each for 6 h daily.
Calculate the electricity bill for the household for the month of June, if cost of electrical energy is Rs.3 per unit.
Answer. Means that if a charge of 1C is moved from one point to another , then 1J of work is done.
Device to measure potential difference is Voltmeter.
b) Heat produced by an element is is given as H= I2RT.
Thus higher the resistance of the element more will be the amount of heat dissipated. Since the resistivity of heating element is very high as compared to connecting cord it would glow.
c) (i) Silver is a better conductor due to its lower resistivity.
(ii) Nichrome should be used in electrical heating devices due to very high resistivity because in heating device we require more heat and heat produced depends on resistance.
Energy consumed per day by refrigerator = 0.4 kW ×10h (P= 400W/1000 = 0.4Kw.)
Energy consumed per day by fans = 2 × 0.08 kW ×6h
Energy consumed per day by electric tubes = 6 ×0.018 kW ×6h
= 0.648 kWh.
Total energy consumption per day = 4 + 0.96 + 0.648
= 5.608 kWh.
Energy consumed in 30 days = 30 ×5.608
Cost of 168.24 units at the rate of Rs.3 per unit = 168.24 ×3= Rs. 504.72