Free PDF Download of CBSE Class 10 Science Chapter 1 Chemical Reactions and Equations Multiple Choice Questions with Answers. MCQ Questions for Class 10 Science with Answers was Prepared Based on Latest Exam Pattern. Students can solve NCERT Class 10 Science Chemical Reactions and Equations Multiple Choice Questions with Answers to know their preparation leve
Q.1. Magnesium ribbon is rubbed before burning because it has a coating of
(a) basic magnesium carbonate
(b) basic magnesium oxide
(c) basic magnesium sulphide
(d) basic magnesium chloride
Answer: a
Q.2. Rancidity can be prevented by
(a) adding antioxidants
(b) storing food away from light
(c) keeping food in refrigerator
(d) all of these
Answer: d
Q.3. Which information is not conveyed by a balanced chemical equation?
(a) Physical states of reactants and products
(b) Symbols and formulae of all the substances involved in a particular reaction
(c) Number of atoms/molecules of the reactants and products formed
(d) Whether a particular reaction is actually feasible or not
Answer: d
Q.4. 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 (crystals)
(a) (i) and (ii)
(b) (ii) and (iii)
(c) (i) and (iv)
(d) (ii) and (iv)
Answer: a
Q.5. Which of the following is not physical change?
(a) Boiling of water to give water vapour
(b) Melting of ice to give water
(c) Dissolution of salt in water
(d) Combustion of Liquefied Petroleum Gas (LPG)
Answer: (d) Combustion of Liquefied Petroleum Gas (LPG)
Q.6. Chemically rust is
(a) hydrated ferrous oxide
(b) only ferric oxide
(c) hydrated ferric oxide
(d) none of these
Answer: c
Q.7. Oxidation is a process which involves
(a) addition of oxygen
(b) addition of hydrogen
(c) removal of oxygen
(d) removal of hydrogen
Answer: a
Q.8. Which of the following is true for an unbalanced chemical equation?
(a) Number of atoms is equal on both sides of the equation
(b) Number of atoms is less on the left side of the equation
(c) Number of atoms is more on the right side of the equation
(d) Both (b) and (c).
Answer: (d) Both (b) and (c).
Q.9. Which of the following gases can be used for storage of fresh sampel of an oil for a long time?
(a) Carbon dioxide or oxygen
(b) Nitrogen or helium
(c) Helium or oxygen
(d) Nitrogen or oxygen
Answer: b
Q.10. The process of reduction involves
(a) addition of oxygen
(b) addition of hydrogen
(c) removal of oxygen
(d) removal of hydrogen
Answer: b
Q.11. Which of the following is Not True with respect to the neutralisation reaction?
(a) Salt is formed.
(b) Reaction occurs between an acid and a base.
(c) Reactive element displaces less reactive element.
(d) Reactants are in gaseous state.
Answer: (d) Reactants are in gaseous state.
Q.12. 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 decomposition of chlorine gas from silver chloride
(iv) oxidation of silver chloride
(a) (i) only
(b) (i) and (iii)
(c) (ii) and (iii)
(d) (iv) only
Answer: a
Q.13. In the decomposition of lead (II) nitrate to give lead (II) oxide, nitrogen dioxide and oxygen gas, the coefficient of nitrogen dioxide (in the balanced equation) is
(a) 1
(b) 2
(c) 3
(d) 4
Answer: d
Q.14. Fatty foods become rancid due to the process of
(a) oxidation
(b) corrosion
(c) reduction
(d) hydrogenation
Answer: a
Q.15. Which of the following is an endothermic process?
(a) Dilution of sulphuric acid
(b) Sublimation of dry ice
(c) Condensation of water vapours
(d) Respiration in human beings
Answer: b
Q.16. Combustion reactions are always
(a) Exothermic
(b) Endothermic
(c) Sometimes exothermic
(d) Both (a) and (b).
Answer: (a) Exothermic
Q.17. We store silver chloride in a dark coloured bottle because it is
(a) a white solid
(b) undergoes redoc reaction
(c) to avoid action by sunlight
(d) none of the above
Answer: c
Q.18. What type of chemical reactions take place when electricity is passed through water?
(a) Displacement
(b) Combination
(c) Decomposition
(d) Double displacement
Answer: c
Q.19. A substance added to food containing fats and oils is called:
(a) Oxidant
(b) Rancid
(c) Coolant
(d) Antioxidant
Answer: d
Q.20. In the double displacement reaction between aqueous potassium iodide and aqueous lead nitrate, a yellow precipitate of lead iodide is formed. While performing the activity if lead nitrate is not available, which of the following can be used in place of lead nitrate?
(a) Lead sulphate (insoluble)
(b) Lead acetate
(c) Ammonium nitrate
(d) Potassium sulphate
Answer: (b) Lead acetate
Q.21. What type of chemical reactions take place when electricity is passed through water?
(a) Displacement
(b) Combination
(c) Decomposition
(d) Double displacement
Answer: c
Q.22. Which of the following is an endothermic process?
(a) Dilution of sulphuric acid
(b) Sublimation of dry ice
(c) Condensation of water vapours
(d) Respiration in human beings
Answer: b
Q.23. Electrolysis of water is a decomposition reaction. The mole ratio of hydrogen and oxygen gases liberated during electrolysis of water is:
(a) 1 : 1
(b) 2:1
(c) 4:1
(d) 1:2
Answer: b
Q.24. The condition produced by aerial oxidation of fats and oils in foods marked by unpleasant smell and taste is called:
(a) antioxidation
(b) reduction
(c) rancidity
(d) corrosion
Answer: c
Q.25. When carbon dioxide is passed through lime water
(a) calcium hydroxide is formed
(b) white precipitate of CaO is formed
(c) lime water turns milky
(d) colour of lime water disappears.
Answer: c
Q.26. Name the products formed when iron filings are heated with dilute hydrochloric acid
(a) Fe (III) chloride and water
(b) Fe (II) chloride and water
(c) Fe (II) chloride and hydrogen gas
(d) Fe (III) chloride and hydrogen gas
Answer: d
Q.27. In which of the following, heat energy will be evolved?
(a) Electrolysis of water
(b) Dissolution of NH4Cl in water
(c) Burning of L.P.G.
(d) Decomposition of AgBr in the presence of sunlight
Answer: c
Q.28. Dilute hydrochloric acid is added to granulated zinc taken in a test tube. The following observations are recorded. Point out the correct observation.
(a) The surface of metal becomes shining
(b) The reaction mixture turns milky
(c) Odour of a pungent smelling gas is recorded
(d) A colourless and odourless gas is evolved
Answer: d
Q.29. Which of the following gases can be used for storage
(a) Carbon dioxide or Oxygen
(b) Nitrogen or Oxygen
(c) Carbon dioxide or Helium
(d) Helium or Nitrogen
Answer: d
Q.30. 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 (crystals)
(a) (i) and (ii)
(b) (ii) and (iii)
(c) (i) and (iv)
(d) (ii) and (iv)
Answer: a