Chapter 16, Problem 95E

Nitrogen monoxide reacts with chlorine gas according to the reaction:

$\text{2NO}\left(\text{g}\right)+{\text{Cl}}_{\text{2}}\left(\text{g}\right)\rightleftharpoons \text{2NOCl}\left(\text{g}\right)$K_p= 0.27 at 700 K
A reaction mixture initially contains equal partial pressures of NO and Cl₂. At equilibrium, the partial pressure of NOCI is 115 torr. What were the initial partial pressures of NO and Cl₂?