Question

Classify the following chemical reactions into different types and also give reasons:
1. CaO + H2O Ca (OH)2
2. H2SO4 + 2NaOH Na2SO4 + 2 H2O
3. AgCl sunlight Ag + Cl2
4. Zn + HCl ZnCl2 + H2

Answer 1

Answer:-

1) CaO + H₂O ⟶ Ca(OH)₂ ⟹ Chemical Combination reaction.

The chemical reaction in which two or more elements or compounds combine and form a single product is termed as Chemical Combination reaction.

Here, CaO & H₂O react(combine) to form a single product, Ca(OH)₂.

2) H₂SO₄ + 2NaOH ⟶ Na₂SO₄ + 2H₂O ⟹ Chemical Double displacement reaction.

The reaction where two elements of different compounds displace each other according to their reactivity and form more than 1 product is called Chemical Double displacement reaction.

Here, Hydrogen & Sodium displace each other and form Na₂SO₄ & 2H₂O.

3) AgCl ⟶ Ag + Cl₂ ⟹ Chemical Decomposition reaction.

The reaction in which, a compound splits or decomposes into two or more compounds or elements is called a Chemical Decomposition reaction.

In the above equation, AgCl is being decomposed into two elements Ag and Cl.

4) Zn + HCl ⟶ ZnCl₂ + H₂ ⟹ Chemical Displacement reaction.

The reaction in which, a high reactive element displaces the low reactive element in its compound to form two or more products is called a Chemical Displacement reaction.

Zn is more reactive than H. So, it displaces H and form ZnCl₂ along with H₂.

Answer 2

Answer:

Required Answer :-

1] CaO + H₂O ⇒ Ca(OH)₂

The given reaction is an example of Chemical combination reaction.

This is because the both elements are mixed and they are forming a single compound.

2] H₂SO₄ + 2NaOH ⇒ Na₂SO₄ + 2H₂O

The given reaction is an example of Chemical Double displacement

This is because both element are forming two compounds.

3] AgCl ⇒ Ag + Cl₂

The given reaction is an example of Chemical Decomposition reaction.

This is because we may see that the compound is divided into two parts.

4]  Zn + HCl  ⇒  ZnCl₂ + H₂

The given reaction is an example of Chemical Displacement reaction.

This is because the Zn and HCI reacts with H₂ which is less reactive than Zinc.