What is the Difference Between Limiting Reactant and Excess Reactant?

The difference between a limiting reactant and an excess reactant lies in the amount of product they produce in a chemical reaction:

Limiting Reactant: This is the reactant that will be consumed completely during the reaction. Once it is used up, the reaction cannot proceed, and it limits the amount of product that can be produced. The limiting reactant determines how much product can be formed.
Excess Reactant: This is the reactant that could keep reacting if the other reactant had not been consumed. It produces more of the product than the limiting reactant, but its excess is not used up in the reaction.

In summary, the limiting reactant is the one that determines the amount of product formed in a reaction, while the excess reactant produces more product than the limiting reactant but does not completely react. To identify the limiting and excess reactants, it is essential to have a balanced chemical equation for the reaction.

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What is the Difference Between Limiting Reactant and Excess Reactant?

Comparative Table: Limiting Reactant vs Excess Reactant

Here is a table that highlights the differences between limiting reactants and excess reactants:

Feature	Limiting Reactant	Excess Reactant
Definition	A limiting reactant is a substance that limits the amount of product produced in a chemical reaction, as it is present in a smaller quantity than other reactants and is completely consumed when the reaction is complete.	An excess reactant is a substance that is present in a larger quantity than other reactants and is not completely used up when the reaction is complete.
Consumption	The limiting reactant is completely consumed during the reaction, and its relative amount determines how much product can be produced.	The excess reactant is not completely consumed during the reaction, and some of it remains after the reaction is complete.
Theoretical Yield	The theoretical yield of a reaction is determined by the limiting reactant, as it is the substance that controls how much product can be produced.	The excess reactant does not affect the theoretical yield, as it is present in a quantity that exceeds the limiting reactant.
Percent Yield	The percent yield of a reaction is calculated by comparing the actual yield to the theoretical yield, which is determined by the limiting reactant.	The excess reactant does not affect the percent yield, as it is present in excess and does not impact the amount of product actually produced.

In summary, a limiting reactant controls the amount of product produced in a chemical reaction, while an excess reactant is present in a larger quantity and does not affect the amount of product produced.

Guilherme Mazui

Guilherme Mazui is graduated in journalism from the Federal University of Minas Gerais (UFMG) and a master's degree in Communication from the University of São Paulo (USP). In addition, he has experience in advertising writing and has worked as a content editor in several companies.