A sample of $\mathrm{HI}\left(\mathrm{g}\right)$ is placed in a flask at a pressure of $0.2 \mathrm{atm}.$ At equilibrium, partial pressure of $\mathrm{HI}\left(\mathrm{g}\right)$ is $0.04 \mathrm{atm}.$ What is $\mathrm{Kp}$ for the given equilibrium ? $2\mathrm{HI}\left(\mathrm{g}\right)\rightleftharpoons {\mathrm{H}}_2( \mathrm{g})+{\mathrm{I}}_2\left(\mathrm{g}\right)$

In a reaction $\mathrm{A}+\mathrm{B}\rightleftharpoons \mathrm{C}+\mathrm{D},$ Le Chatelier's principle asserts that an equilibrium between $\mathrm{A}$ and $\mathrm{B}$ producing $\mathrm{C}$ and $\mathrm{D}$ can be shifted towards $\mathrm{C}$ and $\mathrm{D}$ by
(i) increasing the concentration of $\mathrm{A}$ or $\mathrm{B}$

(ii)increasing the concentration of $\mathrm{C}$ or $\mathrm{D}$

(iii) decreasing the concentration of $\mathrm{A}$ or $\mathrm{B}$