How can the limiting reagent in a chemical reaction be identified?

Identifying the limiting reagent in a chemical reaction is effectively done by calculating the number of moles of each reactant involved in the reaction. The limiting reagent is the reactant that is consumed first, preventing any further reaction from occurring.

To determine which reactant is the limiting reagent, one begins by establishing the stoichiometric relationship from the balanced chemical equation. By calculating the initial number of moles for each reactant, it becomes possible to identify which one will run out first based on the reaction ratios. This method provides a clear and mathematical approach to understand how much of each reactant is present and how they relate to one another in the reaction, leading to the conclusion of which reagent limits the extent of the reaction.

Other approaches, such as measuring temperature changes, analyzing color changes, or comparing weights after the reaction, do not directly address the stoichiometry of the reactants and can be influenced by various external factors, making them less reliable for accurately identifying the limiting reagent.