Question

The extent of a reaction is 10, and the stoichiometric coefficient of O2 is 2.5, if the moles of O2 entering the process is 45, what is the percentage of excess air?

(a) 20%

(b) 40%

(c) 60%

(d) 80%

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I need to ask this question from Material Balances Involving Combustion topic in division The Chemical Reaction Equation & Stoichometry, Material Balances for Processes Involving Reaction and Multiple Units of Basic Chemical Engineering

Answer 1

Correct answer is (d) 80%

To elaborate: Moles of O2 required = 10*2.5 = 25, => Percentage of excess air = 100*(45 – 25)/25 = 80%.