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Question
What is a chemical equation? Why it is necessary to balance it?
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Solution
A chemical equation is the symbolic representation of a chemical reaction using the symbols and formulae of the substances involved in the reaction.
A chemical equation needs to be balanced because a chemical reaction is just a rearrangement of atoms.
Atoms themselves are neither created nor destroyed during the course of a chemical reaction.
The chemical equation needs to be balanced to follow the law of conservation of mass.
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