Final answer:
The percent yield of CO2 when 4.000 moles of C8H18 react with 4.000 moles of O2 is approximately 25.00%, as calculated using the limiting reactant and stoichiometry from the balanced chemical reaction.
Step-by-step explanation:
The question is asking to calculate the percent yield of carbon dioxide (CO2) when 4.000 moles of C8H18 react with 4.000 moles of O2. According to the balanced chemical reaction, 2 moles of C8H18 react with 25 moles of O2 to produce 16 moles of CO2. As there are fewer moles of O2 available than required for a stoichiometric reaction, O2 is the limiting reactant. First, we need to find the theoretical yield of CO2 based on the limiting reactant (O2), which in this case will produce 2.56 moles of CO2 (since 4.000 moles of O2 would fully react with just 0.32 moles of C8H18 to produce 2.56 moles of CO2 using the mole ratio from the balanced equation). With a molar mass of CO2 as 44.010 g/mol, the theoretical yield is 112.666 g of CO2. The percent yield is then the actual yield (28.16 g) divided by the theoretical yield (112.666 g) times 100%, which equals approximately 25.00%.