percent yield. theoretical yield the maximum amount of product that can be produced from a given...

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Percent Yield

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Page 1: Percent Yield. Theoretical Yield The maximum amount of product that can be produced from a given amount of reactant Theoretical yield is calculated using

Percent Yield

Page 2: Percent Yield. Theoretical Yield The maximum amount of product that can be produced from a given amount of reactant Theoretical yield is calculated using

Theoretical Yield

The maximum amount of product that can be produced from a given amount of reactant

Theoretical yield is calculated using stoichiometry

Page 3: Percent Yield. Theoretical Yield The maximum amount of product that can be produced from a given amount of reactant Theoretical yield is calculated using

Actual Yield

The amount of product actually produced when the chemical reaction is carried out in an experiment

Page 4: Percent Yield. Theoretical Yield The maximum amount of product that can be produced from a given amount of reactant Theoretical yield is calculated using

Percent Yield

A comparison of the actual and theoretical yield

In general, the higher the yield, the better the results are from the experiment.% Yield = actual yield

(experiment)

theoretical yield

(calculation)

× 100

Page 5: Percent Yield. Theoretical Yield The maximum amount of product that can be produced from a given amount of reactant Theoretical yield is calculated using

Steps

1. Identify what is given in the problem. A. One product and one reactant (go to step 2)B. One product and two reactants (go to step 3)

2. The product given is the actual yield, calculate the theoretical yield using stoichiometry and the reactant given

3. The product given is the actual yield, calculate the limiting reactant and that becomes your theoretical yield

4. Calculate the percent yield using the equation

Page 6: Percent Yield. Theoretical Yield The maximum amount of product that can be produced from a given amount of reactant Theoretical yield is calculated using

Determine the theoretical yield of Ag2CrO4 if 0.500 g of AgNO3 is used to react with K2CrO4. Also if 0.455 g of

Ag2CrO4 is obtained from an experiment, calculate the percent yield.

2 AgNO3 + 1 K2CrO4 1 Ag2CrO4 + 2 KNO3

= 0.488 g AgCrO4

0.500g AgNO3 1 mol AgNO3 1 mol AgCrO4 331.74 g AgCrO4

169.88 g AgNO3 2 mol AgNO3 1 mol

AgCrO4

% Yield = Actual 0.455 g AgCrO4 Theoretical 0.488 g AgCrO4

×100 =

×100 = 93.2%

Page 7: Percent Yield. Theoretical Yield The maximum amount of product that can be produced from a given amount of reactant Theoretical yield is calculated using

100.0g CS2 1 mol CS2 1 mol CCl4 153.8 g CCl4

76.15 g CS2 1 mol CS2 1 mol CCl4

CCl4 was prepared by reacting 100.0 g of CS2 and 100.0 g Cl2. Calculate the

theoretical yield and percent yield if 65.0 g of CCl4 was obtained from the reaction.

1 CS2 + 3 Cl2 1 CCl4 + 1 S2Cl2

% Yield = Actual 65.0 g CCl4 Theoretical 72.31 g CCl4

×100 =

×100 = 89.9%

= 202.0 g CCl4

100.0g Cl2 1 mol Cl2 1 mol CCl4 153.8 g Ccl4

70.90 g Cl2 3 mol Cl2 1 mol CCl4

= 72.31 g CCl4

L.R. = theoretical

Page 8: Percent Yield. Theoretical Yield The maximum amount of product that can be produced from a given amount of reactant Theoretical yield is calculated using

= 110.5 g AgBr100.0g AgNO3 1 mol AgNO3 2 mol AgBr 187.77 g AgBr

169.88 g AgNO3 2 mol AgNO3 1 mol AgBr

200.0g MgBr2 1 mol MgBr2 2 mol AgBr 187.77 g AgBr

184.11 g MgBr2 1 mol MgBr2 1 mol AgBr

Silver bromide (AgBr) was prepared by reacting 200.0 g of magnesium bromide and

100.0 g of silver nitrate. Calculate the theoretical and percent yield if 100.0 g of silver

bromide was obtained from the reaction.

1 MgBr2 + 2 AgNO3 1 Mg(NO3)2 + 2 AgBr

% Yield = Actual 100.0 g AgBr Theoretical 110.5 g AgBr

×100 =

×100 = 90.5%

=408.0g AgBr

L.R. = theoretical