Partial pressures and the equilibrium constant KpAQA A-Level Chemistry: Mind map

Exam questions on Partial pressures and the equilibrium constant Kp

1. Dinitrogen tetroxide decomposes reversibly: N₂O₄(g) ⇌ 2NO₂(g). A sample of 1.00 mol of N₂O₄ is allowed to reach equilibrium in a sealed vessel at constant temperature. At equilibrium the mixture contains 0.60 mol of N₂O₄ and 0.80 mol of NO₂ and the total pressure is 200 kPa.
   Calculate the partial pressure of each gas in the equilibrium mixture.2 marks
2. Ammonia is made in the Haber process: N₂(g) + 3H₂(g) ⇌ 2NH₃(g), ΔH = −92 kJ mol⁻¹. An iron catalyst is used.
   State and explain the effect of the iron catalyst on the value of Kp and on the position of equilibrium.2 marks
3. In a sealed vessel, 1.00 mol of phosphorus(V) chloride is heated at constant temperature until equilibrium is reached: PCl₅(g) ⇌ PCl₃(g) + Cl₂(g). The equilibrium mixture contains 0.40 mol of PCl₅, 0.60 mol of PCl₃ and 0.60 mol of Cl₂, and the total pressure is 150 kPa.
   Calculate the value of Kp for this equilibrium, and state its units.3 marks