MDCAT Chemistry MCQ #2215

If the equilibrium constant (Kc) for the formation of HI from H2 and I2 is 0.25 at a specific temperature, what is Kc for the dissociation of HI?

MDCAT Chemistry MCQ #2215

  1. Question 1

    Q1. If the equilibrium constant (Kc) for the formation of HI from H2 and I2 is 0.25 at a specific temperature, what is Kc for the dissociation of HI?

    • A) 0.25
    • B) 0.50
    • C) 2.0
    • D) 4.0

    Answer: 4.0

    Explanation: Kc for the reverse reaction is the reciprocal of the forward Kc; 1 / 0.25 = 4. Option A is simply the forward constant.