Question

10 moles of oxygen divides and enters two reactors flow rate 45 kg/s and leaves the reactors at the flow rates of 6 kg/s and 9 kg/s, what are number of moles of oxygen that leaves the reactor with 9 kg/s?

(a) 180

(b) 450

(c) 60

(d) 90

The question was posed to me by my school teacher while I was bunking the class.

I need to ask this question from Flow Rate in division Moles, Density & Concentration of Basic Chemical Engineering

Answer 1

The correct answer is (d) 90

The best explanation: Let number of moles entering and leaving the second reactor be n1 and n2 respectively, applying reaction equilibrium equation to whole system, => 10*45 = n*(6 + 9), => n = 30, => Applying reaction equilibrium equation to both the reactors separately, => n1*45 = n2*9 => n2 = 5n1, and (10 – n1)*45 = (30 – n2)*6, Solving both equations we get n2 = 90.