Limiting Reactants and Limiting Reactants and Percentage YieldPercentage Yield

9.29.2

ReactantsReactants

Excess ReactantExcess Reactant – will not be – will not be completely ______ up in a completely ______ up in a ______ that goes to ________________ that goes to __________Limiting ReactantLimiting Reactant – is ________ – is ________ completely in a ________ that completely in a ________ that goes to ___________goes to ___________Sandwich exampleSandwich example

Limiting ReactantLimiting Reactant

If there are 152.5 grams of CO If there are 152.5 grams of CO and 24.50 g of Hand 24.50 g of H22, how much , how much

CHCH33OH could be produced?OH could be produced?

Need a balanced equationNeed a balanced equation

CO + 2HCO + 2H22 CH CH33OHOH

Determine # of moles of productDetermine # of moles of product

Limiting ReactantLimiting Reactant

With 752.4 grams of ZnCOWith 752.4 grams of ZnCO33 and and

1921 grams of C1921 grams of C66HH88OO77, which is the , which is the

limiting reactant?limiting reactant?

How much ZnHow much Zn33(C(C66HH55OO77))22 is is

produced?produced?

3ZnCO3ZnCO3 3 + 2C+ 2C66HH88OO77 Zn Zn33(C(C66HH55OO77))22

+ 3CO+ 3CO33

Limiting ReactantLimiting Reactant

Identify the limiting reactant and Identify the limiting reactant and calculate the theoretical yield of calculate the theoretical yield of phosphorous acid (Hphosphorous acid (H33POPO33) if 225 ) if 225

grams of PClgrams of PCl33 is mixed with 123 is mixed with 123

grams of Hgrams of H22O.O.

PClPCl33 + 3H + 3H22O O H H33POPO33 + 3HCl + 3HCl

YieldYield

Actual YieldActual Yield – _________ amount – _________ amount of ________ from a reaction.of ________ from a reaction.

Doesn’t always _______ amounts Doesn’t always _______ amounts that it __________.that it __________.

–Don’t go to _____________Don’t go to _____________

–________ equilibrium________ equilibrium

–Not _____ situationsNot _____ situations

Percent YieldPercent Yield

% Yield% Yield – ____ of _____ ____to – ____ of _____ ____to the ____________ yield the ____________ yield multiplied by ____multiplied by ____

% yield = % yield = actual yieldactual yield x 100 x 100 theoretical yieldtheoretical yield

Calculating % YieldCalculating % Yield

Determine the limiting reactant, Determine the limiting reactant, the theoretical yield (in grams), if the theoretical yield (in grams), if 14.0 g of N14.0 g of N22 are mixed with 9.0g are mixed with 9.0g

HH22..

NN22 + H + H22 NH NH3 3

Calculating % YieldCalculating % Yield

Make sure the equation is Make sure the equation is balanced.balanced.

Find limiting reactant firstFind limiting reactant first

Then identify actual yieldThen identify actual yield

Then calculate % yieldThen calculate % yield

% yield = Actual/Theoretical x 100% yield = Actual/Theoretical x 100

Theoretical YieldTheoretical Yield

Determine the limiting reactant Determine the limiting reactant and the theoretical yield if 16.1 and the theoretical yield if 16.1 grams of bromine are mixed with grams of bromine are mixed with 8.42 grams of chlorine.8.42 grams of chlorine.

BrBr22 + Cl + Cl22 2BrCl 2BrCl

Stoichiometry ReviewStoichiometry Review

2N2N22HH44 + (CH + (CH33))22NN22HH22 + 3N + 3N22OO4 4

6N6N22 + 2CO + 2CO22 + 8H + 8H22OO

The density of NThe density of N22HH44 is 0.982 g/mL is 0.982 g/mL

How many mL of NHow many mL of N22HH44 is needed to is needed to

produce 20 grams of Nproduce 20 grams of N22??

Stoichiometry ReviewStoichiometry Review

2N2N22HH44 + (CH + (CH33))22NN22HH22 + 3N + 3N22OO4 4

6N6N22 + 2CO + 2CO22 + 8H + 8H22OO

How many molecules of NHow many molecules of N22HH44 are are

needed to produce 50 grams of needed to produce 50 grams of NN22??