Question

why is it necessary to balance a chemical reaction ?

Answer 1

so that it follows the law of conversation of mass that is why it is necessary to balance a chemical equation

Answer 2

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HERE IS YOUR ANSWER..............
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☜☆☞ The chemical equation needs to bebalanced so that it follows the law of conservation of mass. A balanced chemical equation occurs when the number of the different atoms of elements in the reactants side is equal to that of the products side. Balancing chemical equations is a process of trial and error.
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