Question
What do you mean by 'balancing a chemical equation'? On what principle the balancing of a chemical equation is based?
Solution
When the number of atoms of each element are same on both the sides of an equation, it is called a balanced chemical equation. The principle on which the balancing of a chemical equation is based is ‘Law of Conservation of mass’ or Law of Industructibility of matter, which states: Matter can neither be created nor destroyed in any physical or chemical change. Hence, atom that takes part in a chemical reaction can neither be created nor destroyed. Therefore, in a chemical reaction atoms of each element on both the sides of the arrow 
must be equal.
For example,
must be equal.For example,
