$2NOBr(g) \rightleftharpoons 2NO(g) + Br_2(g)$. If nitrosyl bromide $(NOBr)$ is $40\%$ dissociated at a certain temperature and a total pressure of $0.3 \ atm$,what is the $K_P$ for the reaction $2NO(g) + Br_2(g) \rightleftharpoons 2NOBr(g)$?

Which of the following statements regarding a chemical equilibrium is wrong?

Eight moles of a gas $AB_3$ attained equilibrium in a closed container of volume $1 \, dm^3$. The reaction is $2AB_{3(g)} \rightleftharpoons A_{2(g)} + 3B_{2(g)}$. If at equilibrium $2 \, moles$ of $A_2$ are present,then the equilibrium constant is ...... $mol^2 \, L^{-2}$.

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

For the equilibrium:
$CaCO_{3(s)} \rightleftharpoons CaO_{(s)} + CO_{2(g)}$; $K_{p} = 1.64 \ atm$ at $1000 \ K$.
$50 \ g$ of $CaCO_{3}$ in a $10 \ L$ closed vessel is heated to $1000 \ K$. The percentage of $CaCO_{3}$ that remains unreacted at equilibrium is:
(Given $R = 0.082 \ L \ atm \ K^{-1} \ mol^{-1}$)