Given the equilibrium: $aA + bB + ...\leftrightarrows cC + dD + ...$ Definition of $K_p$: $K_p\;=\;\frac{p_C^cp_D^d..}{p_A^ap_B^b..}$ Relation between $K_p$ and $K$: $K_p=K(RT)^{(c+d+...)-(a+b+...)}$