Limiting Reagent/Reactant

Limiting Reactant: the reactant that is completely consumed because it determines/limits the amount of product formed

Excess Reactant: the other reactant(s), left over

How to identify the limiting reagent:

1) calculate the moles of each reactant

2) compare the mole ratio needed from the balanced equation

3) the limiting reagent is the reactant that is used up first and stops more products being made

How to calculate for excess reactant mass:

1) initial mol - excess reactant mol = moles

2) calculate for mass as usual (mass = moles x Mr)

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