Answer:
%
Explanation:
The ethanol combustion reaction is:
→
If we had the amount (x moles) of ethanol, we would calculate the oxygen moles required:
Dividing the previous equation by x:
We would need 3.30 oxygen moles per ethanol mole.
Then we apply the composition relation between O2 and N2 in the feed air:
Then calculate the oxygen moles number leaving the reactor, considering that 0.85 ethanol moles react and the stoichiometry of the reaction:
Calculate the number of moles of CO2 and water considering the same:
The total number of moles at the reactor output would be:
So, the oxygen mole fraction would be:
%