At the equilibrium N _2 O _4(g) ; ;2 , NO _2(g) obeys

CHEMISTRY · Subjective · A Level · Chemistry · Gaseous equilibria (Kp) · Gaseous equilibria (Kp)

Problem

298\,\text{K}

the equilibrium

\text{N}_2\text{O}_4(g)\;\rightleftharpoons\;2\,\text{NO}_2(g)

obeys

K_p=0.144

. A cylinder with a frictionless, movable piston contains a gaseous mixture at total pressure

1.00\,\text{atm}

with

P_{\text{N}_2\text{O}_4}=0.625\,\text{atm}

and

P_{\text{NO}_2}=0.30\,\text{atm}

. Argon gas is injected until its partial pressure is

0.20\,\text{atm}

, and the piston is then allowed to move so that the total pressure is restored to

1.00\,\text{atm}

while the temperature remains constant. Determine the equilibrium partial pressures of

\text{NO}_2

and

\text{N}_2\text{O}_4

after the system has re-equilibrated.