Transcript Notes - Limiting Reactant

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Limiting Reactant
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This is the
chemical that
is used
completely in
a reaction.
Also called
limiting
reagent.
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Limiting Reactant
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Al2O3 + 6 NaCl  2 AlCl3 + 3 Na2O
If you have 18.0 moles of NaCl and 2.50
moles of Al2O3, which is the limiting
reactant?
Hint: Solve reaction twice for same
product. (AlCl3 for this demo…)
Al2O3 + 6 NaCl  2 AlCl3 + 3 Na2O
18.0 mol NaCl 2 mol AlCl3
6 mol NaCl
= 6.00 mol AlCl3
The reactant that creates the
smaller amount is limiting!
2.50 mol Al2O3 2 mol AlCl3
1 mol Al2O3
= 5.00 mol AlCl3
Limiting Reactant

2 Na +
CaCl2  2 NaCl +
Ca
If you start with 57.5 g of Na and
111 g of CaCl2, how many grams of
Ca will you have at the end of the
reaction?
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Hint: solve the question twice…
2 Na + CaCl2  2 NaCl + Ca
57.5 g Na 1 mol Na 1 mol Ca 40.1 g Ca
23.0 g Na 2 mol Na 1 mol Ca
=50.1 g Ca
111 g CaCl2
1 mol
CaCl2
1 mol Ca
40.1 g Ca
111.1 g
CaCl2
1 mol
CaCl2
1 mol Ca
=40.1 g Ca
Limiting Reactant
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40.1 g of Ca is produced from the 111 g
of CaCl2
The CaCl2 is the limiting reactant.