71 MCQs on Chemical Reactions and Equations Class 10 Science

In this article you will get high quality MCQs. It includes

• “SEBA 10 Years PYQ MCQs”
• “Assertion-Reason MCQs”
• “Statement-Based MCQs”
• “Match the Following MCQs”

To score 100 % in exam we have compiled a collection of important Chemical Reactions and Equations MCQs with answers.

These MCQs cover all key topics from the chapter, including chemical reactions, balanced chemical equations, combination reactions, decomposition reactions, displacement reactions, double displacement reactions, oxidation, reduction, and redox reactions. Practicing these MCQs will help students improve conceptual understanding, enhance problem-solving skills, and perform better in school and SEBA and CBSE board examinations.

1. 4Fe (s) + 3O₂ (g) → Which option of the following shows the compound formed during the above reaction? [HSLC-2025]
   (A) 4FeO₃(s)
   (B) 12FeO(s)
   (C) 3Fe₄O₂(s)
   (D) 2Fe₂O₃(s)

2. Chemical reaction is not involved in [HSLC-2025]
   (A) burning of candle
   (B) melting of candle
   (C) digestion of food
   (D) respiration

3. Fe₂O₃ + 2Al → Al₂O₃ + 2Fe. The above reaction is an example of – [HSLC-2016, 18, 25]
   (A) a combination reaction
   (B) a decomposition reaction
   (C) a displacement reaction
   (D) a double displacement reaction

4. Two statements are given in the question below as Assertion (A) and Reason (R). Read the statements and choose the correct option: [HSLC-2026]

Assertion (A): When CO₂ gas is passed through lime water for a long time, the solution first turns milky and then becomes colourless.

Reason (R): Lime water first changes into calcium carbonate which then changes into calcium-bicarbonate.

(A) Both (A) and (R) are true, but (R) is not the correct explanation of (A).
(B) Both (A) and (R) are true and (R) is the correct explanation of (A).
(C) (A) is true, (R) is false.
(D) (A) is false, (R) is true.

5. Which of the following reaction is used in black and white photography? [HSLC-2026]
   (A) CaCO₃ → Ca + CO₃
   (B) 2AgBr → 2Ag + Br₂
   (C) 2FeSO₄ → Fe₂O₃ + SO₂ + SO₃
   (D) 2Pb(NO₃)₂ → 2PbO + 4NO₂ + O₂

6. When calcium oxide is added to water, it completely dissolves in water. What products are formed in this reaction? [HSLC-2026]
   (A) Ca and H₂
   (B) CaH
   (C) Ca and H₂O
   (D) Ca(OH)₂

7. When manganese dioxide is heated with aluminium powder, the following reaction takes place: 3MnO₂(s) + 4Al(s) → 3Mn(l) + X(s) + Heat. What could be the compound ‘X’? [HSLC-2026]
   (A) 2Al₂O₃
   (B) 2Fe₂O₃
   (C) 2AlCl
   (D) 2MnO

8. Addition of aqueous solution of barium chloride to aqueous solution of sodium sulphate results in insoluble barium sulphate and the solution of sodium chloride. Which of the following is the correct balanced chemical equation with state symbols for the above reaction? [HSLC-2024]
   (A) BaCl(aq) + NaSO₄(aq) → BaSO₄(s) ↓ + NaCl(aq)
   (B) BaCl₂(s) + Na₂SO₄(s) → BaSO₄(s) + NaCl(aq)
   (C) BaCl₂(aq) + Na₂SO₄(s) → BaSO₄(aq) + 2NaCl(aq)
   (D) BaCl₂(aq) + Na₂SO₄(aq) → BaSO₄(s) ↓ + 2NaCl(aq)

9. Which of the following does not involve a chemical reaction? [HSLC-2024]
   (A) Digestion of food
   (B) Respiration
   (C) Burning of candle
   (D) Melting of candle

10. Which of the following laws is satisfied by a balanced chemical reaction? [HSLC-2024]
    (A) Conservation of momentum
    (B) Conservation of mass
    (C) Conservation of energy
    (D) Conservation of density

11. Which of the following statements is true for an oxidizing agent? [HSLC-2024]
    (A) It gives hydrogen
    (B) It gives oxygen
    (C) It takes oxygen
    (D) None of the above

12. Decomposition of vegetable matter into compost is an example of which class of reaction? [HSLC-2023]
    (A) Endothermic reaction
    (B) Exothermic reaction
    (C) Both
    (D) None of the above

13. An element reacts with oxygen to give a compound with a high melting point. This compound is soluble in water. The element is likely to be – [HSLC-2022]
    (A) Calcium
    (B) Carbon
    (C) Silicon
    (D) Iron

14. What happens when dilute hydrochloric acid is added to iron filings? [HSLC-2017]
    (A) Hydrogen gas and iron chloride are produced.
    (B) Chlorine gas and iron hydroxide are produced.
    (C) No reaction takes place.
    (D) Iron salt and water are produced.

15. The ratio of hydrogen and oxygen present in water by volume is:
    (A) 1:2
    (B) 1:1
    (C) 2:1
    (D) 1:4

16. Identify x, y and z in the following balanced equation: x Pb(NO₃)₂ (s) → y PbO(s) + z NO₂(g) + O₂(g)
    (A) x=2, y=4, z=2
    (B) x=2, y=2, z=4
    (C) x=4, y=2, z=4
    (D) x=4, y=4, z=2

17. BaCl₂ + H₂SO₄ → BaSO₄ + 2HCl. The above reaction is an example of:
    (A) Displacement reaction
    (B) Double Displacement reaction
    (C) Precipitation reaction
    (D) Both (B) and (C)

18. Which of the following is not produced on the thermal decomposition of lead nitrate?
    (A) PbO
    (B) NO₂
    (C) N₂
    (D) O₂

19. The colour of the solution when zinc metal reacts with copper sulphate solution will be:
    (A) Blue
    (B) Colourless
    (C) Green
    (D) Reddish

20. When Rahul heated Ferrous Sulphate crystals in a test tube he observed:
    (i) Green colour changes to yellow
    (ii) Green colour changes to white
    (iii) Blue colour changes to brownish colour
    (iv) Smell of burning of Sulfur is obtained

(A) (i), (iv)
(B) (ii), (iv)
(C) (ii), (iii)
(D) (i), (iii)

21. Select the correct answer to these statements:
    (i) White silver chloride turns grey in sunlight.
    (ii) Decomposition of silver chloride in presence of sunlight takes place to form silver metal and chlorine gas.

(A) i is correct but ii is incorrect
(B) i is incorrect but ii is correct
(C) i and ii both are correct
(D) i and ii both are incorrect

22. Fe₂O₃ + 2Al → Al₂O₃ + 2Fe. This reaction is an example of:
    (A) Combination reaction
    (B) Double displacement reaction
    (C) Decomposition reaction
    (D) Displacement reaction

23. A substance added to food containing fats and oil is called:
    (A) Oxidant
    (B) Rancidity
    (C) Coolant
    (D) Antioxidant

24. Which of the following changes represent a chemical reaction?
    (A) Changes in states
    (B) Formation of gases
    (C) Changes of temperature
    (D) All of the above

25. Which one of the following is a balanced chemical reaction?
    (A) 2Mg + O₂ → 2MgO
    (B) Mg + O₂ → 2MgO
    (C) Mg + O₂ → MgO
    (D) 2Mg + O₂ → MgO

28. Which of the following reaction is a displacement reaction:
    (A) X+YZ → XY+Z
    (B) X + Y → XY
    (C) XYZ → YZX
    (D) XY+AB → XA+YB

29. ‘X’ has been burnt and after burning a fine white powder is obtained. What is ‘X’?
    (A) Sodium
    (B) Calcium
    (C) Magnesium
    (D) Aluminium

30. Pb(NO₃)₂ + KI → KNO₃ + PbI₂. Identify the type of reaction.
    (A) Combination reaction
    (B) Decomposition reaction
    (C) Double displacement reaction
    (D) Oxidation reaction

31. A small iron nail is dipped into blue copper sulphate solution. The blue colour disappears and the nail turns brownish. This chemical reaction is:
    (A) Redox reaction
    (B) Displacement reaction
    (C) Combination reaction
    (D) Double displacement reaction

32. In the reaction: CuO + H₂ → Cu + H₂O
    (i) CuO is oxidised
    (ii) H₂ is oxidised
    (iii) CuO is reduced
    (iv) H₂ is reduced

(A) (i) and (ii) correct
(B) (i) and (iv) correct
(C) (ii) and (iii) correct
(D) (ii) and (iv) correct

33. Which of the following statements about the reaction 3Fe(s) + 4H₂O(g) → Fe₃O₄(s) + 4H₂(g) are correct?
    (i) Iron metal is getting oxidised
    (ii) Water is getting reduced
    (iii) Water is acting as reducing agent
    (iv) Water is acting as oxidising agent

(A) (i), (ii) and (iii)
(B) (iii) and (iv)
(C) (i), (ii) and (iv)
(D) only (iv)

34. MnO₂ + xHCl → MnCl₂ + yH₂O + zCl₂. Values of x, y and z are:
    (A) 6, 2, 2
    (B) 4, 1, 2
    (C) 4, 2, 1
    (D) 2, 2, 1

35. In the balanced equation aCH₄ + bO₂ → cCO₂ + dH₂O, values of a, b, c, d are:
    (A) 1, 1, 2, 2
    (B) 1, 2, 1, 2
    (C) 2, 1, 2, 1
    (D) 2, 2, 1, 1

36. Na₂SO₄(aq) + BaCl₂(aq) → BaSO₄(s) + 2NaCl(aq). This reaction is:
    (A) Combination reaction
    (B) Double displacement reaction
    (C) Decomposition reaction
    (D) Displacement reaction

37. Identify the oxidising agent in the reaction: H₂S + Cl₂ → S + 2HCl
    (A) Cl₂
    (B) H₂S
    (C) S
    (D) HCl

38. Photosynthesis is a type of:
    (A) Combination reaction
    (B) Endothermic reaction
    (C) Exothermic reaction
    (D) Decomposition reaction

39. Ferrous sulphate heated in a test tube gives gas smelling like burning sulphur. This is:
    (A) Combination reaction
    (B) Decomposition reaction
    (C) Displacement reaction
    (D) Double displacement reaction

41. Statement I: Mass cannot be created or destroyed in chemical reaction.
    Statement II: While balancing equation, formula of reactants/products cannot be changed.
    Choose correct option.

(A) both the statements are correct
(B) both the statements are incorrect
(C) only statements I is correct
(D) only statements II is correct

42. The reaction 4NH₃(g)+5O₂(g)→4NO(g)+6H₂O(g) is an example of:
    (i) Displacement reaction
    (ii) Combination reaction
    (iii) Redox reaction
    (iv) Neutralisation reaction

(A) (i) only
(B) (ii) only
(C) (iii) only
(D) (iv) only

43. Which among the following statement(s) is/are true? Exposure of silver chloride to sunlight for a long duration turns grey due to –
    (i) The formation of silver by decomposition of silver chloride
    (ii) Sublimation of silver chloride
    (iii) Reduction of silver chloride
    (iv) Oxidation of silver chloride

(A) (i) only
(B) (ii) and (iii)
(C) (i) and (iii)
(D) (iv) only

45. When we burn a magnesium ribbon, it burns with a dazzling white flame and changes into a white powder. The chemical formula of the white powder is:
    (A) MgCl₂
    (B) MgO
    (C) Mg₂O
    (D) MgO₂

46. For balancing Fe + H₂O → Fe₃O₄ + H₂, number of H₂O molecules needed is:
    (A) 1
    (B) 2
    (C) 3
    (D) 4

47. CaO + H₂O → Ca(OH)₂ is:
    (A) Decomposition reaction
    (B) Combination reaction
    (C) Exothermic reaction
    (D) Both (b) and (c)

48. Match Column I and Column II:

(A) A-(ii), B-(i), C-(iv), D-(iii)
(B) A-(iv), B-(iii), C-(ii), D-(i)
(C) A-(iii), B-(ii), C-(iv), D-(i)
(D) A-(iv), B-(iii), C-(i), D-(ii)

49. Fe₂O₃ + 2Al → Al₂O₃ + 2Fe is:
    (A) Combination reaction
    (B) Double displacement reaction
    (C) Decomposition reaction
    (D) Displacement reaction

50. Which of the following correctly represents a balanced chemical equation?
    (A) Fe + 4H₂O → Fe₃O₄ + 4H₂
    (B) 3Fe + 4H₂O → Fe₃O₄ + 4H₂
    (C) 3Fe + H₂O → Fe₃O₄ + H₂
    (D) 3Fe + 4H₂O → Fe₂O₄ + H₂

51. When lead nitrate is heated, brown fumes are emitted. Identify the brown fumes –
    (A) NO
    (B) NO₂
    (C) PbO
    (D) O₂

52. The following reaction is an example of a:
    ZnO + C → Zn + CO

(i) Displacement reaction
(ii) Combination reaction
(iii) Redox reaction
(iv) Neutralisation reaction

(A) (i) and (iv)
(B) (ii) and (iii)
(C) (i) and (iii)
(D) (iii) and (iv)

53. Which of the following are exothermic processes?
    (i) Reaction of water with quick lime
    (ii) Dilution of an acid
    (iii) Evaporation of water
    (iv) Sublimation of camphor

(A) (i) and (iv)
(B) (i) and (ii)
(C) (iii) and (iv)
(D) (ii) and (iii)

54. Which of the following correctly represents a balanced chemical equation?
    (A) 3Fe(s) + 4H₂O(g) → Fe₃O₄(s) + 4H₂(g)
    (B) 3Fe(s) + 4H₂O(g) → Fe₂O₄(s) + 4H₂(g)
    (C) 3Fe(s) + H₂O(g) → Fe₁O₄(s) + H₂(g)
    (D) 3Fe(s) + 4H₂O(g) → Fe₁O₄(s) + H₂(g)

55. Food companies fill chips packets with nitrogen gas to:
    (A) Prevent rancidity
    (B) Keep mosquitoes away
    (C) Keep chips dry
    (D) Prevent spilling

56. Identify the exothermic reaction(s) among the following:
    (i) CaCO₃(s) → CaO(s) + CO₂(g)
    (ii) C₆H₁₂O₆(aq) + 6O₂(g) + 6H₂O(l) → 6CO₂(g) + 12H₂O(l) + Energy
    (iii) 2AgCl(s) → (Sunlight) 2Ag(s) + Cl₂(g)
    (iv) CaO(s) + H₂O(l) → Ca(OH)₂(aq)

(A) (i) and (ii)
(B) (ii) and (iv)
(C) (i) and (iii)
(D) (ii) and (iv)

57. The reaction of Hydrogen Sulphide with Chlorine is given below:
    H₂S + Cl₂ → S + 2HCl

Find the correct answer which represents the substance oxidised and reduced?

Substance oxidised | Substance Reduced

(A) Cl₂ | Cl₂
(B) H₂S | H₂S
(C) H₂S | Cl₂
(D) Cl₂ | H₂S

58. Which of the statements about the reaction below are incorrect?
    2PbO(s) + C(s) → 2Pb(s) + CO₂(g)

(i) Lead is getting reduced
(ii) Carbon dioxide is getting oxidised
(iii) Carbon is getting oxidised
(iv) Lead oxide is getting reduced

(A) (i) and (ii)
(B) (i) and (iii)
(C) (i), (ii) and (iii)
(D) All

59. Example of double displacement reaction is:
    (A) A + B → AB
    (B) AB → A + B
    (C) AB + CD → AC + BD
    (D) AB + C → AC + B

60. pAl₂(SO₄)₃ + qNaOH → rAl(OH)₃ + sNa₂SO₄. In order to balance the above chemical reaction, the values of p, q, r and s are:
    (A) 1, 6, 2, 3
    (B) 2, 3, 1, 2
    (C) 1, 6, 3, 2
    (D) 1, 3, 6, 2

61. Statement A: The reaction in which oxygen is added is called oxidation.
    Statement B: Rancidity is an oxidation reaction.

(A) Both Statement A and B are correct
(B) Statement A is correct, B is incorrect
(C) Statement A is incorrect, B is correct
(D) Both the statements A and B are incorrect

62. Assertion (A): Silver bromide decomposition is used in black and white photography.
    Reason (R): Light provides energy for this exothermic reaction.

(A) Both A and B are true and R is the correct explanation of A
(B) Both A and B are true but R is not the correct explanation of A
(C) A is true, but R is false
(D) A is false, but R is true

63. Choose double displacement reaction:
    (A) XYZ → XYZ
    (B) XY → XY
    (C) XYZ + YZX
    (D) XY + AB → XA + YB

64. When magnesium is burned in air: 2Mg + O₂ → 2MgO. Which statement is true about this reaction?
    (A) It is a decomposition reaction
    (B) Magnesium is oxidized to magnesium oxide
    (C) Oxygen is reduced to magnesium oxide
    (D) It is an example of a displacement reaction

65. Which of the following represents a chemical change?
    (A) Evaporation of water
    (B) Melting of ice
    (C) Melting of candles
    (D) Rusting of iron

66. What happens to mass during a chemical reaction?
    (A) Remains the same
    (B) It decreases
    (C) It increases
    (D) Can’t be predicted

67. The colour of the solution observed after 1 hour of placing iron metal into copper sulphate solution is—
    (A) Blue
    (B) Dirty green
    (C) Colourless
    (D) Red

68. In XHNO₃ + YCa(OH)₂ → Ca(NO₃)₂ + ZH₂O, values of X, Y, Z are:
    (A) 2, 1, 2
    (B) 1, 1, 2
    (C) 1, 2, 2
    (D) 2, 2, 1

69. Select the decomposition reaction from following in which energy for decomposition is light
    (A) 2FeSO₄ → Fe₂O₃ + SO₂ + SO₃
    (B) 2H₂O → 2H₂ + O₂
    (C) 2AgCl → 2Ag + Cl₂
    (D) CaCO₃ → CaO + CO₂

70. Assertion (A): In electrolysis of water the volume of hydrogen liberated is twice the volume of oxygen.
    Reason (R): In water molecule hydrogen and oxygen in ratio 1 : 2.

(A) Both A and R are true, and R is the correct explanation of A
(B) Both A and R are true, and R is not the correct explanation of A
(C) Only A is true but R is false
(D) Only A is false but R is true

71. Which of the following reactions are the example of exothermic reaction?
    (i) Burning of natural gas
    (ii) Decomposition of vegetable into compost
    (iii) Decomposition of Ferrous Sulphate into ferric oxide
    (iv) Respiration

(A) (i), (ii), (iii)
(B) (i), (ii), (iv)
(C) (i), (iii), (iv)
(D) (ii), (iii), (iv)