Assignment - Chemical Reaction & Equation, Class 10, Science PDF Download

Fill in the blanks 

1. The reaction CaCO₃ CaO + CO₂ is a ........... reaction.

2. The reaction in which oxygen in added to the substance is called ............. reaction

3. Reaction in which hydgen is added to a substance is called ............. reaction. 

4. The process of loss of an electron in known as ............. and the process of gain of an electron is known as ............. 

5. The species undergoing oxidation acts as a ............. agent.

6. The reducing agent undergoes ............. of electrons.

7. Formation of Nitric oxide from nitrogen and oxygen is a ............. reaction.

8. The potato chips manufacturers uses ............. gas to flush the chips bags to prevent the chips getting oxidsed.

9. Reaction in which energy is absorbed is known as ............. reaction.

10. The reaction in which heat is given out along with products is known as ............. reaction.

11. Digestion of food in our body is an example of ............. reaction.

ANSWER KEY

Fill in the blanks 

1. Decomposition 2. Oxidation  3. Reduction  4. Oxidation, reduction

5. Reducing 6. loss  7. combination 8. Nitrogen

9. Endothermic 10. Exothermic 11. Combustion

Match the following 

1.   Column-A Column-B

Types of chemical reaction        Chemical equation

(A) Combination reactoin                (i) Zn + H₂SO₄ → ZnSO₄ + H₂

(B) Oxidation & reduction reaction  (ii) 2H₂O  2H₂ + O₂

(C) Decomposition reaction            (iii) CaO + CO₂ → CaCO₃

(D) Displacement reaction              (iv) H₂ + Cl₂ → 2HCl

(E) Double displacement reaction   (v) BaCl₂ + Na₂SO₄ → BaSO₄ ¯ + NaCl

Match the following  

(A) → (iii), (iv) ; (B) → (ii). (iv) ; (C) → (ii) ; (D) → (i) ; (E) → (v)

Very Short Answer Questions 

1. Is it possible to have combustion without oxygen?

2. Can a double displacement reaction be a redox reaction?

3. What happens when a strip of zinc is dipped in a copper sulfate solution?

4. Is copper more reactive than iron? Give a reaction in support of your answer _

5. In which type of reaction does an exchange of partner takes place?

6. (Based on activities) Why a dilute acid is added to water during electrolysis of water?

7. Name the product obtained on cathode during electrolysis of water

8. Is the volume of gases produced during the electrolysis of water is the same? If not then what is the ratio in between them?

9. What will happen if silver bromide is kept for some time in sunlight?

10. Write names of three metals which do not corrode?

11. Name two antioxidants which are usually added to fat and oil-containing foods to prevent rancidity.

Short Answer Questions :_ 

1. What do you mean by a precipitation reaction?

2. Why should a magnesium ribbon be cleaned before burning in air?

3. Write a balanced chemical equation with symbols for the following reactions _  

(i) Solutions of barium chloride and sodium sulfate in water react to give insoluble barium sulfate and the solution of sodium chloride.

(ii) Sodium hydroxide solution (in water) reacts with a hydrochloric acid solution (in water) to produce sodium chloride solution and water.  

4. Write the balanced equation for the following chemical reactions.

(i) Hydrogen + chlorine → Hydrogen chloride.

(ii) Barium chloride + Aluminium Sulphate → Barium sulphate + Aluminium chloride.

(iii) Sodium + water ¾® Sodium hydroxide + Hydrogen.

5. How can you say that respiration is an exothermic process?

Name two biochemical reaction which are exothermic.

6. Why blue colour of copper sulphate solution becomes faded when iron fillings are added to it?

7. What happens when copper turnings are added to silver nitrate solution?  

8. Why the solution of silver nitrate becomes blue in colour after some time when copper turnings are added to it?

9. A solution of a substance 'X' is used for white washing _

(i) Name the substance 'X' and write the formula.

(ii) Write the reaction of the above substance 'X' with water.

10. Why is the amount of gas double in test tube during the electrolytic decomposition of water? Name the gas?

11. When a green iron salt is heated strongly, its colour finally changes to black and odour of burning sulphur is given out.  

(i) Name the iron salt

(ii) Name the type of reaction that takes place during the heating of iron salt.

(iii) Write the chemical equation for the reaction involved.

12. Write one equation each for decomposition reactions where energy is supplied by heat, light and electricity.

13. What is the difference between displacement and double displacement reactions? Write equations for these reactions.

14. Classify each of the following reactions as combination, decomposition, displacement or double displacement reaction.

(i) H₂ + Cl₂ → 2HCl

(ii) 2KClO₃  2KCl + 3O₂ 

(iii) Zn + CuSO₄ → ZnSO₄ + Cu

Blue Colour less

(iv) 2Pb(NO₃)₂ 2PbO_(s) + 4NO₂(g) + O₂(g)  

(v) NaOH + HCl → NaCl + H₂O

(vi) BaCl₂ + H₂SO₄ → BaSO₄ + 2HCl  

(vii) CaO + CO₂ → CaCO₃ 

(viii) CaCO₃ CaO + CO₂ 

(ix) 2KI + Cl₂ → 2KCl + I₂ 

ANSWER KEY

Chemical reaction & equation

Very short answer type 

1. No  2. No  3. Blue colour of solution fade up.

4. No, because iron is more reactive metal than copper.

Fe + CuSO₄ ¾® FeSO₄ + Cu

5. Double displacement reaction. 6. To increase the ionization of water.

7. Hydrogen gas  8. No, H₂ : O₂ (2 : 1)

9. Photochemical reaction takes place.

2AgBr ¾® 2Ag(s) + Br₂(g)

10. Silver, Gold, Platinum.

11. (a) BHA (Butylated Hydroxy Anisole) 

(b) BHT (Butylated Hydroxy Toluene) 
 

Short Answer 

14. (i) Combination reaction (ii) Decomposition reaction (iii) Displacement reaction

(iv) Decomposition reaction] (v) In double displacement reaction  Neutralization reaction

(vi) Double displacement reaction (vii) Combination reaction (viii) Decomposition reaction

(ix) Displacement reaction (x) Decomposition reaction