Give the percent yield when 28.16 g of CO2 are formed from the reaction of 5.000 moles of C8H18 with 2.500 moles of O2.
2 C8H18 + 25 O2 → 16 CO2 + 18 H2O
First, calculate the theoretical yield of CO2 based on the provided amounts of C8H18 and O2.
From the balanced equation, it is clear that 2 moles of C8H18 react with 25 moles of O2 to produce 16 moles of CO2. Therefore, according to the stoichiometry of the reaction, the molar ratio of C8H18 to CO2 is 2:16 or 1:8. This means that for every mole of C8H18, 8 moles of CO2 are produced.
Given:
5.000 moles of C8H18
2.500 moles of O2
Since the molar ratio of C8H18 to CO2 is 1:8, 5.000 moles of C8H18 will produce:
5.000 moles C8H18 x 8 moles CO2/1 mole C8H18 = 40 moles CO2
Calculating the mass of 40 moles of CO2:
40 moles CO2 x 44.01 g/mol = 1760.4 g
Therefore, the theoretical yield of CO2 is 1760.4 g.
Now, calculate the percent yield.
Given:
Actual yield = 28.16 g
Percent yield = (actual yield / theoretical yield) x 100
Percent yield = (28.16 / 1760.4) x 100
Percent yield = 0.016 x 100
Percent yield = 1.6%
Therefore, the percent yield is 1.6% for the reaction.