Question

Part A (7 points): How many grams of iron (Fe) will be produced if you start with 3.65 liters of carbon monoxide gas (CO) at STP? Fe2O3 + 3 CO --> 2 Fe + 3 CO2 Part B (3 points): Jacob performed the above experiment in his chemistry class, and collected 4.23 grams of iron. What is the percent yield?

Answer 1

The balanced chemical equation for the above reaction is as follows;
Fe₂O₃ +  3CO --> 2 Fe + 3 CO₂
stoichiometry of CO to Fe produced is 3:2
Molar volume is where 1 mol of any gas occupies a volume of 22.4 L 
If 22.4 L contains 1 mol of CO
then 3.65 L contains - 1/22.4 x 3.65 = 0.16 mol 
the number of CO moles reacting - 0.16 mol
If 3 mol of CO produces 2 mol of Fe
then 0.16 mol of CO produces - 2/3 x 0.16 = 0.106 mol
mass of Fe produced - 0.106 mol x 55.8 g/mol = 5.91 g

B)
the theoretical yield of Fe, when 0.16 mol of CO reacts - 5.91 g
however the actual yield - 4.23 g 
to find the percent yield = actual yield /theoretical yield x 100 %
percent yield of Fe - 4.23 / 5.91 x 100% = 71.6%