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Question
Why should an equation be balanced? Explain with the help of a simple equation.
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Solution
According to the law of conservation of mass, 'matter can neither be created nor can it be destroyed'. This is possible only if the total number of atoms on the reactants side is equal to the total number of atoms on the products side. Thus, a chemical reaction should always be balanced.
e.g. KNO3 → KNO2 + O2
In this equation, the number of atoms on both sides is not the same, and the equation is not balanced.
The balanced form of this equation is
2KNO3 → 2KNO2 + O2
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