The relationship between $K_p$ and $K_c$ is $K_p=K_c(R T)^{\Delta n}$. What would be the value of $\Delta n$ for the reaction $$ \mathrm{NH}_4 \mathrm{Cl}(s) \rightleftharpoons \mathrm{NH}_3(g)+\mathrm{HCl}(g) ? $$

The reaction quotient ' $Q$ ' is useful inpredicting the direction of the reaction. Which of the following is incorrect?

The equilibrium constant for the reaction $\mathrm{N}_2(g)+\mathrm{O}_2(g) \rightleftharpoons 2 \mathrm{NO}(\mathrm{g})$ is $4 \times 10^{-4}$ at 2000 K . In presence of a catalyst the equilibrium is attained ten times faster. Therefore the equilibrium constant in presence of catalyst 2000 K is