Question

H2 at 27^oC with pressure 10 atm and volume 10 liter is passed through a reactor with 6 moles of oxygen, if the limiting reagent reacts completely, how many moles of oxygen is left unreacted?

(a) 1

(b) 2

(c) 4

(d) 6

Answer 1

Correct choice is (c) 4

Explanation: The reaction is 2H2 + O2 -> 2H2O, moles of H2 passed = 10*10/(0.0821*300) = 4, => moles of H2 reacted = 4, => moles of O2 reacted = 4, => moles of O2 left unreacted = 6 – 2 = 4.