Answer:
The theoretical yield of carbon dioxide formed is 68.4 grams CO2
Explanation:
Step 1: Data given
Liquid octane = C8H18
gaseous oxygen gas = O2
gaseous carbon dioxide = CO2
gaseous water = H2O
Mass of octane = 27.4 grams
Molar mass of octane = 114.23 g/mol
Mass of oxygen = 77.8 grams
Molar mass of oxygen = 32.0 g/mol
Step 2: The reaction
2C8H18(l) + 25O2(g) → 16CO2(g) + 18H2O(g)
Step 3: Calculate number of moles
Moles = mass / molar mass
Moles of octane = 27.4 grams / 114.23 g/mol
Moles of octane = 0.240 moles
Moles of oxygen = 77.8 grams / 32.0 g/mol
Moles of oxygen = 2.43 moles
Step 4: Calculate the moles of the products
For 2 moles of octane we need 25 moles of O2 to produce 16 moles of CO2 and 18 moles H2O
O2 is the limiting reactant. It will completely react. (2.43 moles).
There will react 2.43/12.5 = 0.194 moles
There will remain 0.240 - 0.194 = 0.046 moles of octane.
There will be produced:
16/25 * 2.43 = 1.555 moles of CO2
18/25 * 2.43 = 1.750 moles of H2O
This is:
1.56 moles * 44.01 g/mol = 68.4 grams CO2
1.750 moles * 18.02 g/mol = 31.5 grams H2O
The theoretical yield of carbon dioxide formed is 68.4 grams CO2
