What is decomposition reaction?Explain all kinds of decomposition reaction? (2+3=5 marks)
What is decomposition reaction?Explain all kinds of decomposition reaction? (2+3=5 marks)
Decomposition Reaction: It is a very simple type of chemical reaction in which a single compound splits into two or more simple substances under suitable condition. It is just opposite of combination reaction.
The generalised rection for decomposition is ; AB ---> A + B
For ex: 2H2O ---> 2H2 + O2
Types:- The decomposition reaction can be classified into three main types as follows;
- Thermal Decomposition (Thermolysis) reaction: In this type of reaction, a simple substance or compound is broken into two or more simple parts when heated. The reaction is endothermic as heat is required to break the bond.
For Ex:- Calcium carbonate (lime stone) CaCO3 is decomposed by heating.
CaCO3 ---> CaO + CO2
2. Electrolytic decomposition (Electrolysis) reaction: When an electric current is passed through an aqueous solution of a simple compound, it breaks in two or more parts and the process is called electrolysis.
For Ex:- decomposition of water
2H2O ---> 2H2 + O2
3. Photodecomposition (Photolysis) reaction: It is a simple decomposition reaction in which, a substance is broken down into smaller parts by the supply of light energy.
For ex:- Decomposition of silver chloride AgCl ; when AgCl is placed in a watch glass and exposed to sunlight, its white colour changes to grey which conforms decomposition as;
2AgCl (white solid) ---> 2Ag (grey solid) + Cl2 (gas)
Decomposition Reaction: It is a very simple type of chemical reaction in which a single compound splits into two or more simple substances under suitable condition. It is just opposite of combination reaction.
The generalised rection for decomposition is ; AB ---> A + B
For ex: 2H2O ---> 2H2 + O2
Types:- The decomposition reaction can be classified into three main types as follows;
- Thermal Decomposition (Thermolysis) reaction: In this type of reaction, a simple substance or compound is broken into two or more simple parts when heated. The reaction is endothermic as heat is required to break the bond.
For Ex:- Calcium carbonate (lime stone) CaCO3 is decomposed by heating.
CaCO3 ---> CaO + CO2
2. Electrolytic decomposition (Electrolysis) reaction: When an electric current is passed through an aqueous solution of a simple compound, it breaks in two or more parts and the process is called electrolysis.
For Ex:- decomposition of water
2H2O ---> 2H2 + O2
3. Photodecomposition (Photolysis) reaction: It is a simple decomposition reaction in which, a substance is broken down into smaller parts by the supply of light energy.
For ex:- Decomposition of silver chloride AgCl ; when AgCl is placed in a watch glass and exposed to sunlight, its white colour changes to grey which conforms decomposition as;
2AgCl (white solid) ---> 2Ag (grey solid) + Cl2 (gas)
