Concept:Stoichiometry is fundamentally built upon the premise that atoms are never created or destroyed in chemical reactions. They merely rearrange. Thus, the total mass before and after a reaction must be identical.
Formula:$$ \text{Mass of Reactants} = \text{Mass of Products} $$
Solution:- The Law of Conservation of Mass states that matter can neither be created nor destroyed.
- When we balance a chemical equation for stoichiometric calculations, we are physically ensuring that the number of atoms for every element is identical on both sides.
- This direct balancing act is the practical application of the Law of Conservation of Mass (alongside the Law of Definite Proportions).
Why other options are incorrect:- Law of conservation of energy: While true in physics, it is not the basis for balancing atoms in reaction stoichiometry.
- Avogadro’s law: Applies specifically to volumes of gases, not generalized stoichiometry involving solids and liquids.
- Dalton’s law: Pertains to partial pressures of non-reacting gas mixtures, entirely unrelated to mass balancing.
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