Answer to Question #63331 in General Chemistry for Chris

Question

At a particular temperature, Kp=70.9 for the following reaction.
N2O4(g) <=> 2NO2(g)
A certain pressure of N2O4 is initially added to an otherwise evacuated rigid vessel. At equilibrium, 25.8% of N2O4 remains. Determine the partial pressure of NO2 at equilibrium

Answer 1

Following the equation N2O4 = 2NO2 the rate constant can be written as [NO2]^2/[N2O4] = Kp. Thus, if P(NO2) = 0.258x and P(N2O4) = 0.742x then 70.9 = [0.258x]^2/[0.742x] = 70.9. x = 790 and P(NO2) = 204 mmHg.