For the equilibrium $N_2O_4(g) \rightleftharpoons 2NO_2(g)$ in a closed vessel at a constant temperature,if the volume of the reaction vessel is halved,which of the following statements is true regarding the equilibrium constant $K_p$ and the degree of dissociation $(\alpha)$?

One mole of $N_2O_4(g)$ is taken in a closed vessel at $300 \, K$ under $1 \, atm$ pressure. When it is heated to $600 \, K$,$20 \%$ of $N_2O_4(g)$ dissociates into $NO_2(g)$. What is the final pressure in $atm$?

$8 \ mol$ of $AB_{3(g)}$ are introduced into a $1.0 \ dm^3$ vessel. If it dissociates as $2AB_{3(g)} \rightleftharpoons A_{2(g)} + 3B_{2(g)}$. At equilibrium,$2 \ mol$ of $A_2$ are found to be present. The equilibrium constant of this reaction is

$0.6 \ mol$ of $NH_3$ in a reaction vessel of $2 \ dm^3$ capacity was brought to equilibrium. The vessel was then found to contain $0.15 \ mol$ of $H_2$ formed by the reaction $2NH_{3(g)} \rightleftharpoons N_{2(g)} + 3H_{2(g)}$. Which of the following statements is true?

In reaction $A + 2B \rightleftharpoons 2C + D$,the initial concentration of $B$ was $1.5$ times that of $[A]$,but at equilibrium,the concentrations of $A$ and $B$ became equal. The equilibrium constant for the reaction is:

Dissociation of a gas $A_2$ takes place according to the following chemical reaction. At equilibrium, the total pressure is $1 \ bar$ at $300 \ K$.
$A_{2(g)} \rightleftharpoons 2A_{(g)}$
The standard Gibbs energy of formation of the involved substances has been provided below:

Substance	$\Delta G_f^{\circ} / kJ \ mol^{-1}$
$A_2$	$-100.00$
$A$	$-50.832$

The degree of dissociation of $A_{2(g)}$ is given by $(x \times 10^{-2})^{1/2}$ where $x =$ . . . . . . . (Nearest integer).
[Given: $R = 8.3 \ J \ mol^{-1} \ K^{-1}$, $\ln 2 = 0.693$]