For the reaction
2 NO₂(g) ⇌ 2 NO(g) + O₂(g)
Kp = 1.11 × 10⁻⁵ at 200 °C. A 2.50 L vessel at 200 °C is filled with NO₂(g) at an initial pressure of 2.50 atm and allowed to come to equilibrium. What will be the pressure (in atm) of NO(g) at equilibrium?