At a certain temperature,$2HI \rightleftharpoons H_2 + I_2$. If only $50\%$ of $HI$ is dissociated at equilibrium,the equilibrium constant $(K_c)$ is:

$3.00 \, mol$ of $PCl_5$ kept in $1 \, L$ closed reaction vessel was allowed to attain equilibrium at $380 \, K$. Calculate the composition of the mixture at equilibrium. Given $K_c = 1.80$.

For the following reactions,which oxide is more stable?
$X_2 + O_2 \rightleftharpoons 2XO, K_1 = 5$
$X_2 + 2O_2 \rightleftharpoons 2XO_2, K_2 = 10$

For the gas phase reaction; $C_2H_{4(g)} + H_{2(g)} \rightleftharpoons C_2H_{6(g)}$,$\Delta H = -32.7 \ kcal$ carried out in a vessel,the equilibrium concentration of $C_2H_4$ can be increased by:

For the reaction,$H_{2(g)} + I_{2(g)} \rightleftharpoons 2 HI_{(g)}$,the attainment of equilibrium is predicted correctly by:

The equilibrium constants of the following are
$N_2 + 3H_2 \rightleftharpoons 2NH_3 \,; \quad K_1$
$N_2 + O_2 \rightleftharpoons 2NO \,; \quad K_2$
$H_2 + \frac{1}{2} O_2 \rightleftharpoons H_2O \,; \quad K_3$
The equilibrium constant $(K)$ of the reaction:
$2NH_3 + \frac{5}{2} O_2 \rightleftharpoons 2NO + 3H_2O$ is: