University of Virginia Calculation of Inlet Molar Flow Rate Questions

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The reaction of burning of octane is shown below:
2Cg His + 170, 8CO, +18H20
The inlet molar flow rate of C8H18 is 0.9 mol/s, and that of air is 50 mol/s. The
conversion of oxygen (O2) is 70%. Using the extent of reaction () method:
a) Perform degree of freedom (DOF) analysis. (20 pts)
b) Calculate the exit component molar flow rates. (40 pts)
c) As a general rule, combustion processes are performed with excess of air, but
never with fuel in excess. Explain briefly (2-3 sentences) (15 pts)
d) The specification of a process states that the “excess of the reactant is 120%”.
Does this make sense? Explain briefly (2-3 sentences) (15 pts)
e) Give example from everyday life or from the industry where combustion process
is used. (10 pts)