For the formation of ammonia gas from its constituent elements, the $K_p / K_C$ is

For a reaction, $A(s) \rightleftharpoons B(s)+C(g)$ the set of all correct statements are (A) $K$ is independent of $[A]$. (B) $K$ is dependent on partial pressure of $C$ at a given temperature. (C) $\Delta H$ will be independent of temperature. (D) $\Delta H$ is independent of the catalyst addition.

For a given reaction, $2 A \rightleftharpoons B+C$, the equilibrium constant is $2 \times 10^{-3}$. If at any given time the composition of the reaction mixture is $[A]=[B]=[C]=6 \times 10^{-5} \mathrm{M}$; predict in which direction the reaction will proceed and the correct value for reaction quotient.

For a reversible reaction $A \rightleftharpoons B$, pre-exponential factor is same for both the forward and backward reactions and has value of $20 \mathrm{~S}^{-1}$. If the enthalpy change along the forward reaction is $-41.5 \mathrm{~kJ} / \mathrm{mol}$, the value of equilibrium constant at 500 K is