$2$ moles each of $A$ and $B$ were taken in a container and the following reaction takes place: $2 \ A_{(g)} + B_{(g)} \rightleftharpoons 2 \ C_{(g)} + D_{(g)}$. When the system attains equilibrium,which of the following is true?

Given the following equilibria:
$N_2 + 3H_2 \rightleftharpoons 2NH_3 : K_1$
$N_2 + O_2 \rightleftharpoons 2NO : K_2$
$H_2 + 1/2O_2 \rightleftharpoons H_2O : K_3$
Then the equilibrium constant for the reaction $2NH_3 + 5/2O_2 \rightleftharpoons 2NO + 3H_2O$ in terms of $K_1, K_2,$ and $K_3$ will be:

When $20 \ g$ of $CaCO_3$ are subjected to decomposition at $227 \ ^oC$ in a closed container of $10 \ L$ capacity,$50 \%$ of $CaCO_3$ remained unreacted at equilibrium. Calculate $K_P$ for $CaCO_{3(s)} \rightleftharpoons CaO_{(s)} + CO_{2(g)}$ in $atm$.

$1 \ mol$ $N_2$ and $3 \ mol$ $H_2$ are taken in a $4 \ L$ closed vessel at a constant temperature. The reaction is $N_{2(g)} + 3H_{2(g)} \rightleftharpoons 2NH_{3(g)}$. If $0.25\%$ of $N_2$ is converted into ammonia,calculate $K_c$ for this reaction and the $K_c'$ for the reaction $\frac{1}{2}N_{2(g)} + \frac{3}{2}H_{2(g)} \rightleftharpoons NH_{3(g)}$.

Which of the following equations is incorrect?

$56 \, g$ of nitrogen and $8 \, g$ of hydrogen gas are heated in a closed vessel. At equilibrium,$34 \, g$ of ammonia are present. The equilibrium number of moles of nitrogen,hydrogen,and ammonia are respectively: