Question

The equilibrium constant Kp for the reaction C(s)+H2O(g)?CO(g)+H2(g) is 2.44 at 1000 K. What are the equilibrium partial pressures of H2O, CO, and H2 if the initial partial pressures are PCO= 1.25 atm, and PH2= 1.60 atm?

What is the equilibrium partial pressure of H2O?

What is the equilibrium partial pressure of CO?

What is the equilibrium partial pressure of H2?

Answer 1

Balanced equation with ICE table

C(s) + H2O(g) = CO(g) + H2(g)

I 1.25 1.60

C - x +x +x

E - x 1.25+x 1.60+x

Equilibrium constant expression of the reaction

Kp = PCO x PH2 / PH2O

2.44 = (1.25+x)(1.60+x)/(-x)

-2.44x = 2 + 1.25x + 1.60x + x²

x² + 5.29x + 2 = 0

x = - 0.4098

x is negative because the reaction Wil be in the reverse direction

equilibrium partial pressure of H2O = - x = 0.4098 atm

equilibrium partial pressure of CO = 1.25 - 0.4098 = 0.8402 atm

equilibrium partial pressure of H2 = 1.60 - 0.4098 = 1.1902 atm