Chemical Reactions and Equations Class 10 MCQ With Answers

Chemical Reactions and Equations Class 10 MCQ With Answers

Que 1. The reaction of ‘magnesium’ with air is
(a) Exothermic reaction
(b) Endothermic reaction
(c) Reversible reaction
(d) Substitution reaction
Ans 1. (a) Exothermic reaction

Que 2. 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
Ans 2. (a) Basic magnesium carbonate

Que 3. Sodium and chlorine are reacted and as a result, sodium chloride is formed which is also called table salt. What option gives the reactants and products of the reaction?
(a) Reactants – sodium; products – chlorine
(b) Reactants – sodium and table salt; products – chlorine
(c) Reactants – tables salt; products – sodium and chlorine
(d) Reactants – sodium and chlorine; products – sodium chloride
Ans 3. (d) Reactants – sodium and chlorine; products – sodium chloride

Que 4. The chemical formula of lead sulphate is
(a)  Pb₂SO₄
(b)  Pb(SO₄)₂
(c)  PbSO₄
(d)  Pb₂(SO₄)₃
Ans 4. (c)  PbSO₄

Que 5. 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) (iii) and (iv)
Ans 5. (a) (i) and (ii)

Que 6. Before burning in air, the magnesium ribbon is cleaned by rubbing with a sandpaper to:
(a) Make the ribbon surface shinier
(b) Remove the layer of magnesium oxide from the ribbon surface
(c) Remove the layer of magnesium carbonate from the ribbon surface
(d) Remove the moisture from the ribbon surface
Ans 6. (c) Remove the layer of magnesium carbonate from the ribbon surface

Que 7. Which of the following statements about the given reaction are correct?
3Fe (s) + 4H₂O (g) → Fe₃O₄ (s) + 4 H₂ (g)
(i) Iron metal is getting oxidised
(ii) Water is getting reduced
(iii) Water is acting as a reducing agent
(iv) Water is acting as an oxidising agent
(a) (i), (ii) and (iii)
(b) (in) and (iv)
(c) (i), (ii) and (iv)
(d) (ii) and (iv)
Ans 7. (c) (i), (ii) and (iv)

Que 8. Which of the following reactions can also be termed as thermal decomposition reactions?
(a) Combination Reaction
(b) Decomposition Reaction
(c) Displacement reaction
(d) Double displacement reaction
Ans 8. (b) Decomposition Reaction

Que 9. What chemicals are used in fireworks?
(a) Copper chloride
(b) Calcium chloride
(c) Barium chloride
(d) All of above
Ans 9. (d) All of above

Que 10. In a chemical reaction between sulphuric acid and barium chloride solution the white precipitates formed are of
(a) Hydrochloric acid
(b) Barium sulphate
(c) Chlorine
(d) Sulphur
Ans 10. (b) Barium sulphate

Chemical Reactions and Equations Class 10 MCQ With Answers

Que 11. A teacher gave two test tubes to the students, one containing water and the other containing sodium hydroxide. She asked them to identify the test tube containing sodium hydroxide solution. Which one of the following can be used for identification?
(a) Blue litmus
(b) Red litmus
(c) Sodium carbonate solution
(d) Dilute hydrochloric acid
Ans 11. (b) Red litmus

Que 12. 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
Ans 12. (d)  Whether a particular reaction is actually feasible or not

Que 13. A student performs an experiment to form aluminium chloride from aluminium and chlorine. Which options give the chemical equation of the reaction?
(a) Al + Cl₂ → AlCl₂
(b) 2Al + Cl₂ → 2AlCl
(c) 2Al + 3Cl₂ → 2AlCl₃
(d) 3Al + 3Cl₂ → 3AlCl₃
Ans 13. (c) 2Al + 3Cl₂ → 2AlCl₃

Que 14. 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)
Ans 14. (a) (i) and (ii)

Que 15. When a magnesium ribbon is burnt in the air, the ash formed is
(a) Black
(b) White
(c) Yellow
(d) Pink
Ans 15. (b) White

Que 16. The respiration process during which glucose undergoes slow combustion by combining with oxygen in the cells of our body to produce energy is a kind of
(a) Exothermic process
(b) Endothermic process
(c) Reversible process
(d) Physical process
Ans 16. (a) Exothermic process

Que 17. Which of the following is not a 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)
Ans 17. (d) Combustion of Liquefied Petroleum Gas (LPG)

Que 18. Chemically rust is
(a)  Hydrated ferrous oxide
(b)  Only ferric oxide
(c)  Hydrated ferric oxide
(d)  None of these
Ans 18. (c)  hydrated ferric oxide

Que 19. Give the ratio in which hydrogen and oxygen are present in water by volume.
(a) 1:2
(b) 1:1
(c) 2:1
(d) 1:8
Ans 19. (c) 2:1

Que 20. Oxidation is a process that involves
(a) Addition of oxygen
(b) Addition of hydrogen
(c) Removal of oxygen
(d) Removal of hydrogen
Ans 20. (a) addition of oxygen

Chemical Reactions and Equations Class 10 MCQ With Answers

Que 21. If magnesium is gently heated, it forms
(a) Magnesium oxide
(b) Magnesium sulfide
(c) Magnesium nitrite
(d) Magnesium carbonate
Ans 21. (a) Magnesium oxide

Que 22. A chemical reaction does not involve
(a) Formation of new substances having entirely different properties than that of the reactants
(b) Breaking of old chemical bonds and formation of new chemical bonds
(c) Rearrangement of the atoms of reactants to form new products
(d) Changing of the atoms of one element into those of another element to form new products
Ans 22. (d) Changing of the atoms of on element into those of another element to form new products

Que 23. The following reaction is an example of a
4NH₃(g) + 5O₂(g) → 4NO(g) + 6H₂O(g)
(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)
Ans 23. (c) (i) and (iii)

Que 24. Both CO₂ and H₂ gases are
(a)  Heavier than air
(b)  Colourless
(c)  Acidic in nature
(d)  Soluble in water
Ans 24. (b)  Colourless

Que 25. A researcher adds barium hydroxide to hydrochloric acid to form a white-coloured barium chloride. Which option gives the balanced chemical equation of the reaction?
(a) HCl + Ba(OH)₂ → BaCl₂ + 2HOH
(b) 2HCl + Ba(OH)₂ → BaCl₂ + 2HOH
(c) 2HCl + Ba(OH)₂ → BaH₂ + 2HCl + O₂
(d) HCl + 2Ba(OH) → 2BaCl₂ + 2HOH + O₂
Ans 25. b) 2HCl + Ba(OH)₂ → BaCl₂ + 2HOH

Que 26. A student writes a chemical equation of the reaction between carbon monoxide and hydrogen.
CO₂ + 2H₂ → CH₃OH. How can the reaction be classified?
(a) The reaction is an example of a combination reaction as a compound separates into two compounds.
(b) The reaction is an example of a decomposition reaction as a compound dissociates into two compounds.
(c) The reaction is an example of a combination reaction as two compounds react to form a single compound.
(d) The reaction is an example of a decomposition reaction as two compounds react to form a single compound.
Ans 26. (c) The reaction is an example of a combination reaction as two compounds react to form a single compound.

Que 27. Which of the following gases can be used for the storage of fresh samples of oil for a long time?
(a)  Carbon dioxide or oxygen
(b)  Nitrogen or helium
(c)  Helium or oxygen
(d)  Nitrogen or oxygen
Ans 27. (b)  Nitrogen or helium

Que 28. It is necessary to balance a chemical equation in order to satisfy the law of
(a) Conservation of motion
(b) Conservation of momentum
(c) Conservation of energy
(d) Conservation of mass
Ans 28. (d) Conservation of mass

Que 29. Which among the following is (are) double displacement reaction(s)?
(i) Pb + CuCl → PbCl₂ + Cu
(ii) Na₂SO₄ + BaCl₂ → BaSO₄ + 2NaCl
(iii) C + O₂ → CO₂
(iv) CH₄ + 2O₂ → CO₂ + 2H₂O
(a) (i) and (iv)
(b) (ii) only
(c) (i) and (ii)
(d) (iii) and (iv)
Ans 29. (b) (ii) only

Que 30. The process of reduction involves
(a) Addition of oxygen
(b) Addition of hydrogen
(c) Removal of oxygen
(d) Removal of hydrogen
Ans 30. (b) addition of hydrogen

Que 31. Which of the reactions is used in black and white photography?
(a) Combination Reaction
(b) Decomposition Reaction
(c) Displacement reaction
(d) Oxidation reaction
Ans 31. (b) Decomposition Reaction

Que 32. The electrolytic decomposition of water gives H₂ and O₂ in the ratio of
(a)  1:2 by volume
(b)  2:1 by volume
(c)  8:1 by mass
(d)  1:2 by mass
Ans 32. (b)  2:1 by volume

Que 33. Rusting of iron involves a chemical reaction which is a combination of
(a) Reduction as well as combination reactions
(b) Oxidation as well as combination reactions
(c) Reduction as well as displacement reactions
(d) Oxidation as well as displacement reactions
Ans 33. (b) Oxidation as well as combination reactions

Que 34. The following reaction is used for the preparation of oxygen gas in the laboratory
2KClO₃ → 2KCl + 3O₂
Which of the following statement about the reaction is correct?
(a) It is a decomposition reaction and endothermic in nature.
(b) It is a combination reaction.
(c) It is a decomposition reaction accompanied by the release of heat.
(d) It is a photochemical decomposition reaction and exothermic in nature.
Ans 34. (a) It is a decomposition reaction and endothermic in nature.

Que 35. Three beakers labelled as A, B and C each containing 25 ml of water were taken. A small amount of NaOH, anhydrous CuSO₄ and NaCl were added to the beakers A, B and C respectively. It was observed that there was an increase in the temperature of the solution contained in beakers A and B, whereas, in the case of beaker C, the temperature of the solution falls. Which one of the following statement(s) is (are) correct?
(i) In beakers A and B, an exothermic process has occurred.
(ii) In beakers A and B, an endothermic process has occurred.
(iii) In beaker C exothermic process has occurred.
(iv) In beaker C endothermic process has occurred.
(a) (i) only
(b) (ii) only
(c) (i) and (iv)
(d) (iv), (ii) and (iii)
Ans 35. (c) (i) and (iv)

Que 36. What happens when lead nitrate reacts with potassium iodide?
(a) They will not react
(b) A large amount of hydrogen release
(c) Yellow ppt of lead iodide and potassium nitrate will be produced
(d) Evolution of gas will occur
Ans 36. (c) Yellow ppt of lead iodide and potassium nitrate will be produced

Que 37. Fatty foods become rancid due to the process of
(a)  Oxidation
(b)  Corrosion
(c)  Reduction
(d)  Hydrogenation
Ans 37. (a) Oxidation

Que 38. All the methods mentioned below can be used to prevent the food from getting rancid except
i. Storing the food in the air-tight containers
ii. Storing the food in the refrigerator
iii. Keeping the food in clean and covered containers
iv. Always touching the food with clean hands
(a) (i) and (ii)
(b) (i) and (iii)
(c) (i), (iii) and (iv)
(d) (iii) and (iv)
Ans 38. (d) (iii) and (iv)

Que 39. Combustion reactions are always
(a) Exothermic
(b) Endothermic
(c) Sometimes exothermic
(d) Both (a) and (b).
Ans 39. (a) Exothermic

Que 40. MnO₂ + 4HCl → MnCl₂+ 2H₂O + Cl₂ Identify the substance oxidized in the above equation.
(a) MnCl₂
(b) HCl
(c) H₂O
(d) MnO₂
Ans 40. (d) MnO₂

Que 41. When crystals of lead nitrate are heated strongly in a dry test tube
(a) Crystals immediately melt
(b) A brown residue is left
(c) White fumes appear in the tube
(d) A yellow residue is left
Ans 41. (b) A brown residue is left

Que 42. The chemical reaction between potassium chloride and silver nitrate is given by the chemical equation
AgNO₃ + KCl → AgCl + KNO₃. What can be inferred from the chemical equation?
(a) Silver nitrate and potassium undergo a decomposition reaction to form silver chloride and potassium nitrate
(b) Silver nitrate and potassium undergo a displacement reaction to form silver chloride and potassium nitrate
(c) Silver nitrate and potassium undergo a combination reaction to form silver chloride and potassium nitrate
(d) Silver nitrate and potassium undergo double displacement reactions to form silver chloride and potassium nitrate
Ans 42. (d) silver nitrate and potassium undergo double displacement reactions to form silver chloride and potassium nitrate

Que 43. We store silver chloride in a dark coloured bottle because it is
(a)  A white solid
(b)  Undergoes redox reaction
(c)  To avoid action by sunlight
(d)  None of the above
Ans 43. (c)  to avoid action by sunlight

Que 44. When ferrous sulphate is heated strongly it undergoes decomposition to form ferric oxide as a main product accompanied by a change in colour from
(a) Blue to green
(b) Green to blue
(c) Green to brown
(d) Green to yellow
Ans 44. (c) Green to brown

Que 45. Barium chloride on reacting with ammonium sulphate forms barium sulphate and ammonium chloride. Which of the following correctly represents the type of reaction involved?
(i) Displacement reaction
(ii) Precipitation reaction
(iii) Combination reaction
(iv) Double displacement reaction
(a) (i) only
(b) (ii) only
(c) (iv) only
(d) (ii) and (iv)
Ans 45. (d) (ii) and (iv)

Que 46. A substance ‘X’ is used in white-washing and is obtained by heating limestone in the absence of air. Identify ‘X’.
(a) CaOCl₂
(b) Ca (OH)₂
(c) CaO
(d) CaCO₃
Ans 46. (c) CaO

Que 47. Consider equations: Ca⁺²(aq) + 2OH‾(aq) → Ca(OH)₂ (s). The precipitate of calcium hydroxide will be of
(a) Green colour
(b) Blue colour
(c) Brown colour
(d) White colour
Ans 47. (d) White colour

Que 48. The silver article turns black when kept in the open for a few days due to the formation of
(a)  H₂S
(b)  AgS
(c)  AgSO₄
(d)  Ag₂S
Ans 48. (d)  Ag₂S

Que 49. The displacement reaction between iron (III) oxide and a metal X is used for welding the rail tracks. Here X is
(a) Copper granules
(b) Magnesium ribbon
(c) Sodium pellets
(d) Aluminium dust
Ans 49. (d) Aluminium dust

Que 50. Which one of the following processes involves chemical reactions?
(a) Storing of oxygen gas under pressure in a gas cylinder
(b) Liquefaction of air
(c) Keeping petrol in a China dish in the open
(d) Heating copper wire in presence of air at high temperature
Ans 50. (d) Heating copper wire in presence of air at high temperature

Chemical Reactions and Equations Class 10 MCQ With Answers

Chemical Reactions And Equations Class 10 Notes