The gas-phase equilibrium 2SO_2(g)+O_2(g) 2SO_3(g) has an equilibrium constant in…

CHEMISTRY · Multi-part · A Level · Chemistry · Gaseous equilibria (Kp) · Gaseous equilibria (Kp)

Problem

The gas-phase equilibrium

\mathrm{2SO_2(g)+O_2(g) \rightleftharpoons 2SO_3(g)}

has an equilibrium constant in pressure units of

K_p = 3.0\times10^{4}

at 700 K. A sealed 10.0-L container at 700 K is charged with the following quantities of gas: •

n_{\mathrm{SO_2}} = 0.400\,\text{mol}

•

n_{\mathrm{O_2}} = 0.200\,\text{mol}

•

n_{\mathrm{SO_3}} = 0.0500\,\text{mol}

Assume ideal-gas behavior. (a) Determine the numerical value of

K_c

corresponding to the given

K_p

at 700 K. (b) Calculate the reaction quotient

Q_c

for the initial mixture in the container. (c) By comparing

Q_c

K_c

, indicate the direction in which the system will shift to reach equilibrium.