Science
Limiting reagents.
Definition
The limiting reagent is the reactant in a chemical reaction that is completely consumed first, determining the maximum amount of product that can be formed. The other reactant(s) left over are called excess reagents.
How it works · 5 phases
Step by step.
- Write and balance the chemical equation.
- Convert the given amounts of each reactant to moles.
- Use molar ratios from the balanced equation to determine how much product each reactant could produce.
- The reactant that produces the least product is the limiting reagent.
- Calculate the theoretical yield based on the limiting reagent.
Examples
Real-world.
- 1 If you have 3 slices of bread and 5 slices of cheese, bread limits how many sandwiches you can make
- 2 Burning a limited amount of hydrogen gas with excess oxygen to form water
Key Fact
Theoretical yield is always calculated from the limiting reagent.