For which of the following reactions is the relation $\log \frac{K_P}{K_C} + \log RT = 0$ correct?

When $4.5 \, \text{mol}$ each of hydrogen and iodine are heated in a $10 \, \text{L}$ closed vessel,$3 \, \text{mol}$ of $HI$ are formed at equilibrium. The equilibrium constant $K_c$ for the reaction ${H_2} + {I_2} \rightleftharpoons 2HI$ is .........

For the reaction $PCl_{3(g)} + Cl_{2(g)} \rightleftharpoons PCl_{5(g)}$,the value of $K_p$ at $250 \ ^oC$ is $0.61 \ atm^{-1}$. The value of $K_c$ at this temperature will be .... $(mol \ L^{-1})$.

For the reaction $SO_{3(g)} \rightleftharpoons SO_{2(g)} + 1/2 O_{2(g)}$,the equilibrium constant $K_c = 4.9 \times 10^{-2}$. What is the value of $K_c$ for the reaction $2SO_{2(g)} + O_{2(g)} \rightleftharpoons 2SO_{3(g)}$?

For the reaction $A + B \rightleftharpoons C + D$,the initial concentrations of $A$ and $B$ are equal. If the equilibrium concentration of $D$ is twice the equilibrium concentration of $A$,then the equilibrium constant $K_c$ is:

$2 \ mol$ of $PCl_5$ is heated in a closed vessel of $2 \ L$ capacity. When equilibrium is attained,$PCl_5$ is $40\%$ dissociated. The equilibrium constant $K_c$ for the reaction will be ........... $mol/L$.