Analysis of Data
Measuring the Success of a Synthesis

To measure the amount of compound produced, we measure the (percent) yield .

How do we calculate the theoretical yield?

This is the amount of material produced if ALL of our starting material becomes product.

Step 1:
Write down the reaction equation.

Step 2:
Work out which is the limiting reagent by calculating the number of moles of each reagent that you have used. The limiting reagent is the one that determines how much product is produced. Example:

Step 3:
Calculate the amount of expected product (theoretical yield).

1 mole [Co(H₂O) 6 ]Cl₂ reacts to form 1 moles of [Co(NH₃)₆]Cl₃.
Theoretical yield = 6.31 x 10 -4 x molar mass
= 6.31 x 10 -4 x 267.3
= 0.169 g

Step 4:
Calculate the (percentage yield).

Amount of product produced = 0.150 g.
Theoretical yield = 0.169 g.
Yield = 0.150 / 0.169 x 100 % = 88.8 %