engineering chemistry MCQ #2157

For the reaction 2SO2 + O2 ⇌ 2SO3, if Kc = 100 and initial concentrations of SO2 and O2 are 2 M and 1 M, what is [SO3] at equilibrium?

engineering chemistry MCQ #2157

  1. Question 1

    Q1. For the reaction 2SO2 + O2 ⇌ 2SO3, if Kc = 100 and initial concentrations of SO2 and O2 are 2 M and 1 M, what is [SO3] at equilibrium?

    • A) 1.8 M
    • B) 1.5 M
    • C) 1 M
    • D) 0.5 M

    Answer: 1.8 M

    Explanation: Using Kc = [SO3]²/[SO2]²[O2] and assuming x M of SO2 reacts, we get 100 = x²/(2-x)²(1-x/2), solving gives x = 1.8/2 = 0.9, [SO3] = 1.8.