Limiting Reagent
Which is the limiting reagent?
Common Questions
What is a limiting reagent?
The limiting reagent is the reactant that runs out first in a chemical reaction, determining the maximum amount of product that can form. The other reactant(s) are "in excess."
How do you find the limiting reagent?
Convert each reactant amount to moles. Divide each by its stoichiometric coefficient. The reactant with the smallest ratio is the limiting reagent — it produces the least product.
What is theoretical yield?
Theoretical yield is the maximum amount of product that can form based on the limiting reagent. It assumes perfect conversion with no losses. Actual yield is always less than or equal to theoretical yield.
What is percent yield?
Percent yield = (actual yield ÷ theoretical yield) × 100%. It measures how efficient a reaction was. A yield below 100% means some product was lost to side reactions, incomplete reaction, or transfer losses.