Answer to Question #167289 in Chemistry for Shelley

Question

For the following reaction:

2 A(g) ⇌ B(g) + C(g)

Given the following information, what is the equilibrium pressure of B in bar?

Initial pressure of A = 2.632 bar

Initial pressure of B = 0 bar

Initial pressure of C = 0 bar

K = 9.7 x 10-4

Answer 1

Solution:

2A(g) ⇌ B(g) + C(g)

ICE Table:

The K_p expression for the reaction:

K_p = P_B × P_C / P_A²

K_p = 9.7×10^-4

P_B = P_C = 0.5P

P_A = 2.632 - P

Hence,

9.7×10^-4 = 0.5P × 0.5P / (2.632 - P)²

(2.632 - P)² = 257.732 × P²

2.632 - P = 16.054 × P

2.632 = 17.054 × P

P = 0.154 (bar)

P_B = 0.5P = 0.5 × 0.154 bar = 0.077 bar

P_B = 0.077 bar

Answer: The equilibrium pressure of B is 0.077 bar.