Propene, C3H6 (100 g) was subjected to combustion. The actual yield of carbon dioxide is 200 g. Calculate the percent yield of carbon dioxide.
2 C3H6 + 9 O2 → 6 H2O+ 6 CO2
(Molar mass: C=12 g/mol; H= 1g/mol; O =16 g/mol)
The balanced equation tells us that 2 moles of propene react with 9 moles of oxygen gas to produce 6 moles of carbon dioxide.
From the given mass of propene (100 g), we can determine the number of moles using its molar mass:
100 g / 42 g/mol = 2.38 mol
Since 2 moles of propene should produce 6 moles of carbon dioxide (according to the balanced equation), we can calculate the theoretical yield of carbon dioxide:
2.38 mol C3H6 x (6 mol CO2 / 2 mol C3H6) x (44 g CO2 / 1 mol CO2) = 251.52 g CO2
Therefore, the percent yield of carbon dioxide is:
(Actual yield / Theoretical yield) x 100%
= (200 g / 251.52 g) x 100%
= 79.4%
To calculate the percent yield of carbon dioxide, we need to compare the actual yield of carbon dioxide to the theoretical yield of carbon dioxide.
First, let's calculate the theoretical yield of carbon dioxide.
From the balanced equation, we can see that for every 2 moles of propene (C3H6) combusted, we will produce 6 moles of carbon dioxide (CO2).
Molar mass of C3H6 = (3*C) + (6*H) = (3*12 g/mol) + (6*1 g/mol) = 36 g/mol + 6 g/mol = 42 g/mol
So, for 100 g of propene (C3H6), we can find the number of moles:
Number of moles = Mass / Molar mass = 100 g / 42 g/mol ≈ 2.38 mol
From the equation, we know that the stoichiometry of the reaction is 2 moles of propene to 6 moles of carbon dioxide. Therefore, the theoretical yield of carbon dioxide can be calculated as follows:
Theoretical yield of CO2 = (2.38 mol of C3H6) * (6 mol of CO2/2 mol of C3H6) = 7.14 mol
Next, we can calculate the actual yield of carbon dioxide, which is given as 200 g.
The percent yield of carbon dioxide is calculated by dividing the actual yield by the theoretical yield and multiplying by 100%.
Percent yield = (Actual yield / Theoretical yield) * 100%
= (200 g / 7.14 mol) * 100%
≈ 2797%
Therefore, the percent yield of carbon dioxide is approximately 2797%.