Learn about Chemical Reactions and Equations

The topic of Chemical Reactions and Equations includes many subtopics which area explained as follows:

What is a Chemical reaction?

A process in which a new substance is formed is called a chemical reaction. Reactants react to form products.

For example: Sodium metal reacts Oxygen to form Sodium Oxide.

Sodium + Oxygen —->  Sodium Oxide

What is a chemical Equation?

Symbolic representation of a chemical reaction is called a chemical equation.

For example to represent the chemical reaction between Sodium metal and oxygen, the following equation is represented.

Na + O₂       —–> Na₂O

What is a balanced chemical equation?

The chemical equation which has equal number of atoms on left hand side (reactant) and right hand side (product), is called a balanced chemical equation.

In the above equation, the number of atoms is not equal on left and right sides. So we should balance the above equation.

It is to be noted that we cannot change the formula of molecules of elements and compounds to balance. We can only use the number of moles in the front of reactants and products.

Step 1.

Atom of Sodium on left side is 1 while right is 2 so we should equal the number.

2 Na + O₂       —–> Na₂O

Step 2.

Atom of oxygen on left side is 2 while on right is 1 so we should equal this number by dividing the oxygen mole by 2 on left side.

2 Na + 1/2O₂       —–> Na₂O

Step 3.

Lastly the states symbols should be assigned to reactants and products. Sodium is a solid metal at room temperature, Oxygen is a gas while sodium oxide is a white solid.

2 Na(s) + 1/2O₂(g)      —–> Na₂O(s)

What are different types of  chemical reactions?

The chemical reactions are of following types:

1. Combination reactions
2. Decomposition reactions
3. Displacement reactions
4. Double displacement reactions
5. Redox Reactions

Read about Other cbse chemistry topics.