Question

If 13.4 grams of iron (III) oxide reacts with 12.3 grams of carbon monoxide to produce 8.23 g of pure iron, what are the theoretical yield and percent yield of this reaction? Be sure to show the work that you did to solve this problem.
unbalanced equation: Fe2O3 + CO Fe + CO2

Answer 1

Theoretical yield is the amount supposedly produced by the reaction if it was complete. The balanced chemical reaction is:

Fe2O3(s) + 3 CO(g) = 2 Fe(s) + 3 CO2(g)

We use the amounts given for the reactants as the starting point of the calculations. We do as follows:

13.4 g Fe2O3 ( 1 mol / 159.69 g ) = 0.08 mol
12.3 g CO ( 1 mol / 28.01 ) = 0.44 mol

Therefore, the limiting reactant would be Fe2O3. We use this for the theoretical yield.

0.08 mol ( 2 mol Fe / 1 mol Fe2O3 ) = 0.16 mol Fe (THEORETICAL YIELD)
8.23 g ( 1 mol / 55.85 g ) = 0.15 mol Fe ( ACTUAL YIELD)

Percent yield = 0.15 / 0.16 x 100 = 93.75%