Question

At T = 250 °C the reaction PCl5(g) PCl3(g) + Cl2(g) has an equilibrium constant in terms of pressures Kp = 2.15. (a) Suppose the initial partial pressure of PCl5 is 0.548 atm, and PPCl3 = PCl2 = 0.780 atm. Calculate the reaction quotient Qp and state whether the reaction proceeds to the right or to the left as equilibrium is approached

Answer 1

Answer:

To the right

Explanation:

Step 1: Given data

• Partial pressure of PCl₅ (pPCl₅) = 0.548 atm

• Partial pressure of PCl₃ (pCl₃) = 0.780 atm

• Partial pressure of Cl₂ (pCl₂) = 0.780 atm

Step 2: Write the balanced equation

PCl₅(g) ⇄ PCl₃(g) + Cl₂(g)

Step 3: Calculate the pressure reaction quotient

$Q_p = \frac{pPCl_3 \times pCl_2 }{pPCl_5} = \frac{0.780 \times 0.780 }{0.548} =1.11$

Step 4: Determine whether the reaction proceeds to the right or to the left as equilibrium is approached

Since Qp < Kp, the reaction will proceed to the right to attain the equilibrium.