For the reactions:
$2NO + O_2 \rightleftharpoons 2NO_2$; $K_1$
$4NO + 2Cl_2 \rightleftharpoons 4NOCl$; $K_2$
$NO_2 + \frac{1}{2}Cl_2 \rightleftharpoons NOCl + \frac{1}{2}O_2$; $K_3$
Where $K_1, K_2, K_3$ are equilibrium constants,then $K_3^2$ is equal to:

For the reaction $2SO_{2(g)} + O_{2(g)} \rightleftharpoons 2SO_{3(g)}$ at $298 \ K$,the $K_c$ is $7 \times 10^{25}$. Calculate $K_c$ for the reaction $SO_{3(g)} \rightleftharpoons SO_{2(g)} + \frac{1}{2}O_{2(g)}$.

When one mole of $A$ and one mole of $B$ were heated in a one-litre flask at $T \ K$,$0.5 \ mole$ of $C$ was formed at equilibrium for the reaction $A + B \rightleftharpoons C + D$. The equilibrium constant,$K_C$,is:

Some solid $NH_4HS$ is placed in a flask containing $0.5 \ atm$ of $NH_3$. What would be the partial pressures of $NH_3$ and $H_2S$ when equilibrium is reached for the reaction $NH_4HS_{(s)} \rightleftharpoons NH_{3_{(g)}} + H_2S_{(g)}$,given $K_p = 0.11$?

For the reaction $CO_{(g)} + 2H_{2(g)} \rightleftharpoons CH_3OH_{(g)}$,the true condition is:

For the reversible reaction in equilibrium
$N_{2(g)} + O_{2(g)} \underset{k_2}{\overset{k_1}{\longleftrightarrow}} 2NO_{(g)}$
If the rate constant for the forward reaction is $k_1 = 2.1 \times 10^{-3} \ s^{-1}$ and for the backward reaction is $k_2 = 4.2 \times 10^{-4} \ s^{-1}$,then the equilibrium constant $K_c$ for the above reaction is: