CBSE Class 10 Science 2025 — Set 4

Questions in this 2025 Science paper (Set 4)

All 39 questions from this set, exactly as asked. Try each one, then open the question-paper PDF above for the complete paper.

1. 1.
   In which one of the following situations a chemical reaction does not occur?

   • (a) Milk is left open at room temperature during summer
   • (b) Grapes get fermented
   • (c) An iron nail is left exposed to humid atmosphere
   • (d) Melting of glaciers
2. 2.
   In order to prepare dry hydrogen chloride gas in humid atmosphere the gas produced is passed through a guard tube (drying tube) which contains:

   • (a) Calcium chloride
   • (b) Calcium oxide
   • (c) Calcium hydroxide
   • (d) Calcium carbonate
3. 3.
   The property by virtue of which a solid material can be drawn into thin wires is called:

   • (a) Malleability
   • (b) Ductility
   • (c) Rigidity
   • (d) Resistivity
4. 4.
   Select from the following a hydrocarbon having one C–C bond and one C≡C bond:

   • (a) Benzene
   • (b) Cyclohexane
   • (c) Butyne
   • (d) Propyne
5. 5.
   The essential element taken up from the soil by the plants to synthesize proteins is:

   • (a) Phosphorus
   • (b) Nitrogen
   • (c) Iron
   • (d) Magnesium
6. 6.
   Select TRUE statements about lymph from the following: A. Lymph vessels carry lymph through the body and finally open into larger arteries. B. Lymph contains some amount of plasma, proteins and blood cells. C. Lymph contains some amount of plasma, proteins and red blood cells. D. Lymph vessels carry lymph through the body and finally open into larger veins. The true statements are: (a) A and B…
7. 7.
   Plants like rose and banana have lost the capacity to produce:

   • (a) Flowers
   • (b) Buds
   • (c) Seeds
   • (d) Fruits
8. 8.
   In a bisexual flower the male gametes are present in the:

   • (a) Anther
   • (b) Ovary
   • (c) Stigma
   • (d) Filament
9. 9.
   When a pure-tall pea plant is crossed with a pure-dwarf pea plant, the percentage of tall pea plants in F1 and F2 generation will be respectively:

   • (a) 100% ; 25%
   • (b) 100% ; 50%
   • (c) 100% ; 75%
   • (d) 100% ; 100%
10. 10.
    To get an image of magnification -1 on a screen using a lens of focal length 20 cm, the object distance must be:

    • (a) Less than 20 cm
    • (b) 30 cm
    • (c) 40 cm
    • (d) 80 cm
11. 11.
    An optical device 'X' is placed obliquely in the path of a narrow parallel beam of light. If the emergent beam gets displaced laterally, the device 'X' is:

    • (a) Plane mirror
    • (b) Convex lens
    • (c) Glass slab
    • (d) Glass prism
12. 12.
    A piece of wire of resistance 'R' is cut lengthwise into three identical parts. These parts are then connected in parallel. If the equivalent resistance of this combination is R', then the value of R/R' is:

    • (a) 1/9
    • (b) 1/3
    • (c) 3
    • (d) 9
13. 13.
    An electric bulb is rated 220 V; 11W. The resistance of its filament when it glows with a power supply of 220 V is:

    • (a) 4400 Ω
    • (b) 440 Ω
    • (c) 400 Ω
    • (d) 20 Ω
14. 14.
    The minimum number of identical bulbs of rating 4V; 6W, that can work safely with desired brightness, when connected in series with a 240 V mains supply is:

    • (a) 20
    • (b) 40
    • (c) 60
    • (d) 80
15. 15.
    In the food chains given below, select the most efficient food chain in terms of energy:

    • (a) Grass → Grasshopper → Frog → Snake
    • (b) Plants → Deer → Lion
    • (c) Plants → Man
    • (d) Phytoplankton → Zooplankton → Small Fish → Big Fish
16. 16.
    Which one of the following gets biomagnified at different levels in a food chain?

    • (a) Carbon monoxide
    • (b) CFC's
    • (c) DDT
    • (d) Manure
17. 17.
    Assertion (A): In large animals, oxygen can reach different parts of the animal's body easily. Reason (R): Respiratory pigments take up oxygen from the air and carry it to body tissues. Select the correct option:

    • (a) Both Assertion (A) and Reason (R) are true, and Reason (R) is the correct explanation of Assertion (A).
    • (b) Both Assertion (A) and Reason (R) are true, and Reason (R) is not the…
18. 18.
    Assertion (A): Concentrated nitric acid is diluted by adding water slowly to acid with constant stirring. Reason (R): Concentrated nitric acid is easily soluble in water. Select the correct option:

    • (a) Both Assertion (A) and Reason (R) are true, and Reason (R) is the correct explanation of Assertion (A).
    • (b) Both Assertion (A) and Reason (R) are true, and Reason (R) is not the correct…
19. 19.
    Assertion (A): In reptiles, the temperature at which the fertilized eggs are kept decides the sex of the offsprings. Reason (R): Sex is not genetically determined in some animals. Select the correct option:

    • (a) Both Assertion (A) and Reason (R) are true, and Reason (R) is the correct explanation of Assertion (A).
    • (b) Both Assertion (A) and Reason (R) are true, and Reason (R) is not the correct…
20. 20.
    Assertion (A): When ciliary muscles contract, eye lens becomes thin. Reason (R): Ciliary muscles control the power of the eye lens. Select the correct option:

    • (a) Both Assertion (A) and Reason (R) are true, and Reason (R) is the correct explanation of Assertion (A).
    • (b) Both Assertion (A) and Reason (R) are true, and Reason (R) is not the correct explanation of Assertion (A).
    • (c) Assertion (A)…
21. 21.
    Define oxidation. Identify and name the substance oxidised in the following reaction: CuO + H2 → Cu + H2O
22. 22.
    Show the formation of magnesium chloride by electron transfer. Write the name of the cation and anion present in the compound formed. (Atomic Number of Mg = 12, Cl = 17)
23. 23.
    "Plants use a variety of techniques to get rid of waste material." Justify this statement giving any four ways.
24. 24.
    Explain with the help of a flow chart that in human beings father is responsible for the sex (male or female) of the child.
25. 25.
    Draw a ray diagram to show the refraction of a ray of light passing through an equilateral glass prism. Mark the angle through which the emergent ray bends from the direction of the incident ray and also name it.
26. 26.
    What are magnetic field lines? List two important properties of magnetic field lines.
27. 27.
    Why do we balance a chemical equation? Name and state the law that suggests the balancing of a chemical equation. Balance the following chemical equation: Zn + H3PO4 → Zn3(PO4)2 + H2
28. 28.
    Design an activity to show that metals are good conductors of heat and have high melting points.
29. 29.
    The digestion of food in human alimentary canal is a complex process. State the enzyme/salt present in the following and mention their function in the process of digestion:

    • (i) Saliva
    • (ii) Bile Juice
    • (iii) Pancreatic Juice
30. 30.
    State two limitations of electrical impulses in multicellular organisms. Why is chemical communication better than electrical impulses as a means of communication between cells in multicellular organisms?
31. 31.
    If we want to obtain a virtual and magnified image of an object by using a concave mirror of focal length 18 cm, where should the object be placed? Use mirror formula to determine the object distance for an image of magnification +2 produced by this mirror to justify your answer.
32. 32.
    The electrical resistivity of three materials A, B and C at 20°C is given below: Material A: Resistivity = 10^-6 Ωm Material B: Resistivity = 44 × 10^-5 Ωm Material C: Resistivity = 1.62 × 10^-8 Ωm

    • (i) Classify these materials as conductor, alloy and insulator.
    • (ii) Give one example of each of these materials and state one use of each material in the design of an electrical appliance say an…
33. 33.
    What are decomposers? Give two examples. State how they maintain a balance in an ecosystem.
34. 34.
    A carbon compound 'A' on heating with excess conc. H2SO4 forms a compound 'B' which on addition of one mole of hydrogen gas in the presence of nickel catalyst forms a compound 'C'. 'C' on combustion in air forms 2 moles of carbon dioxide and 3 moles of water. Identify 'A', 'B' and 'C' and write their structures. Give chemical equations of the reactions involved. Also state the role of…
35. 35.
    • (i) What is regeneration? Give one example of an organism that shows this process and one organism that does not. Why does regeneration not occur in the latter?
    • (ii) Briefly explain the process of regeneration in the named organism.
36. 36.
    • (i) Draw the pattern of the magnetic field lines for the two parallel straight conductors carrying current of same magnitude 'I' in opposite directions as shown. Show the direction of magnetic field at a point O which is equidistant from the two conductors. (Consider that the conductors are inserted normal to the plane of a rectangular cardboard.)
    • (ii) In our houses we receive A.C. electric…
37. 37.
    Case Study: Common salt is a very important chemical compound for our daily life. Its chemical name is sodium chloride and it is used as a raw material in the manufacture of caustic soda, washing soda, baking soda etc. It is also used in the preservation of pickles, butter, meat etc.
38. 37 (a).
    Name the acid and the base from which common salt can be obtained.
39. 37 (b).
    State the nature (acidic/basic/neutral) of sodium chloride. Give reasons for your justification for your answer.
40. 37 (c).
    (A) What happens when electric current is passed through an aqueous solution of sodium chloride (called brine)? Name the products obtained along with the corresponding places in the electrolytic cell where each of these products is obtained.
41. 38.
    Case Study: In life there are certain changes in the environment called 'stimuli' to which we respond appropriately. Touching a flame suddenly is a dangerous situation for us. One way is to think consciously about the possibility of burning and then moving the hand. But our body has been designed in such a way that we save ourself from such situations immediately.
42. 38 (a).
    Name the action by which we protect ourself in the situation mentioned above and define it.
43. 38 (b).
    Write the role of

    • (a) motor and
    • (b) relay neuron.
44. 38 (c).
    (A) What are the two types of nervous system in human body? Name the components of each of them.
45. 39.
    Case Study: The students in a class took a thick sheet of cardboard and made a small hole in its centre. Sunlight was allowed to fall on this small hole and they obtained a narrow beam of white light. A glass prism was taken and this white light was allowed to fall on one of its faces. The prism was turned slowly until the light that comes out of the opposite face of the prism appeared on the…
46. 39 (a).
    Give any one more instance in which this type of spectrum is observed.
47. 39 (b).
    What happens to white light in the above case?
48. 39 (c).
    (A) List two conditions necessary to observe a rainbow.

Class 10 Science exam pattern (80 marks)

The theory paper carries 80 marks over 3 hours (39 questions, with internal choice in some). Section-wise structure:

Structure per the CBSE 2023-24 sample-paper design; question wording varies by set.

Prepare with

How to use these papers

1. 1Start chapter-wise early in the year — solve only the Science questions from a chapter you have just finished.
2. 2Switch to full timed papers 2–3 months before the exam: one complete set in the real time limit, no notes.
3. 3Self-mark against the marking scheme, then fix every mistake with our free NCERT solutions.
4. 4Re-attempt your weakest chapters until the recurring question types feel routine.

CBSE Class 10 Science 2025 paper — FAQ