Question

one example each the displacement, decomposition andcombination reaction with explanation

Answer 1

One example of these following reactions are -
Displacement reaction Fe+CuSo4=FeSo4+Cu
Combination reaction H2+O2=2H2O
Decomposition reaction H2O=H2+O2

Answer 2

1. Combination reaction

Those reaction in which two or more substance combine to form a single substance, are called combination reaction.

For example-

Magnesium and oxygen combine, when heated, to form magnesium oxide :

2Mg (s) + O2 (g)→ 2MgO (s)

In this reaction, two elements, magnesium and oxygen are combining to form a single compound, magnesium oxide. So,

this is a combination reaction.

The formation of water from hydrogen and oxygen is a combination reaction.

2H2 (g) + O2 (g)→ 2H2O (l)

2. Decomposition reaction

Those reaction in which a compound splits up into two or more simpler substance are known as decomposition

reaction. A decomposition reaction is just the opposite of a combination reaction.

For example-

When calcium carbonate is heated, it decomposes to give calcium oxide and carbon dioxide.

CaCO3 (s)→ CaO (s) + CO2 (g)

3. Displacement reaction

Those reaction in which one element takes place of another element in a compound, are known as displacement

reaction. In general, a more reactive element displaces a less reactive element from its compound.

For example-

When a strip of zinc metal is placed in copper sulphate solution, then zinc sulphate solution and copper are obtained :

CuS04+Zn → ZnSo4 + Cu

In this, reaction, zinc displace copper from copper sulphate compound so that copper is set free(or liberated). The blue

colour of copper sulphate solution fades due to the formation of zinc sulpahte (which is colourless). A red- brown

deposit of copper metal is formed on the zinc strip. This displacement reaction takes place because zinc is more

reactive than copper

.