Question

Consider the following reaction.

2A(g)<--->B(g) Kp=5.65x10^-5 at 500k

If a sample of A(g) at 5.20 atm is heated to 500 K, what is the pressure of B(g) at equilibrium?

Answer 1

2A <---------------------->   B

5.20 atm                      0 atm        initially

5.20 - 2 X                      X   atm     equilibrium

Kp = [P_B] / [P_A]²

0.0000565 = X / [5.20 - 2X]²

0.0000565 = X / 27.04 x 4X² - 20.8 X

0.00153 + 0.000226X² - 0.001175 X = X

0.000226 X² - 1.001175 X   + 0.00153 = 0

X = 0.0015

at equilibrium P_B    = 0.0015 atm